Caffeinated beverage intake and reproductive hormones among premenopausal women in the BioCycle Study.

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Schliep, Karen C; Schisterman, Enrique F; Mumford, Sunni L; Pollack, Anna Z; Zhang, Cuilin; Ye, Aijun; Stanford, Joseph B; Hammoud, Ahmad O; Porucznik, Christina A; Wactawski-Wende, Jean

2012-02-01

Caffeinated beverages are widely consumed among women of reproductive age, but their association with reproductive hormones, and whether race modifies any such associations, is not well understood. We assessed the relation between caffeine and caffeinated beverage intake and reproductive hormones in healthy premenopausal women and evaluated the potential effect modification by race. Participants (n = 259) were followed for up to 2 menstrual cycles and provided fasting blood specimens for hormonal assessment at up to 8 visits per cycle and four 24-h dietary recalls per cycle. Weighted linear mixed models and nonlinear mixed models with harmonic terms were used to estimate associations between caffeine and hormone concentrations, adjusted for age, adiposity, physical activity, energy and alcohol intakes, and perceived stress. On the basis of a priori assumptions, an interaction between race and caffeine was tested, and stratified results are presented. Caffeine intake ≥200 mg/d was inversely associated with free estradiol concentrations among white women (β = -0.15; 95% CI: -0.26, -0.05) and positively associated among Asian women (β = 0.61; 95% CI: 0.31, 0.92). Caffeinated soda intake and green tea intake ≥1 cup/d (1 cup = 240 mL) were positively associated with free estradiol concentrations among all races: β = 0.14 (95% CI: 0.06, 0.22) and β = 0.26 (95% CI: 0.07, 0.45), respectively. Moderate consumption of caffeine was associated with reduced estradiol concentrations among white women, whereas caffeinated soda and green tea intakes were associated with increased estradiol concentrations among all races. Further research is warranted on the association between caffeine and caffeinated beverages and reproductive hormones and whether these relations differ by race.

Maternal caffeine intake during pregnancy and childhood growth and overweight: results from a large Norwegian prospective observational cohort study

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Botton, Jérémie; Brantsæter, Anne-Lise; Haugen, Margaretha; Alexander, Jan; Meltzer, Helle Margrete; Bacelis, Jonas; Elfvin, Anders; Jacobsson, Bo; Sengpiel, Verena

2018-01-01

Objectives To study the association between maternal caffeine intake during pregnancy and the child’s weight gain and overweight risk up to 8 years. Design Prospective nationwide pregnancy cohort. Setting The Norwegian Mother and Child Cohort Study. Participants A total of 50 943 mothers recruited from 2002 to 2008 and their children, after singleton pregnancies, with information about average caffeine intake assessed at mid-pregnancy. Outcome measure Child’s body size information at 11 age points from 6 weeks to 8 years. We defined excess growth in infancy as a WHO weight gain z-score of >0.67 from birth to age 1 year, and overweight according to the International Obesity Task Force. We used a growth model to assess individual growth trajectories. Results Compared with pregnant women with low caffeine intake (200 mg/day had consistently higher weight. Very high caffeine exposures were associated with higher weight gain velocity from infancy to age 8 years. Conclusion Any caffeine consumption during pregnancy is associated with a higher risk of excess infant growth and of childhood overweight, mainly at preschool ages. Maternal caffeine intake may modify the overall weight growth trajectory of the child from birth to 8 years. This study adds supporting evidence for the current advice to reduce caffeine intake during pregnancy. PMID:29685923

Caffeine Intake, Smoking, and Risk of Parkinson Disease in Men and Women

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Liu, Rui; Guo, Xuguang; Park, Yikyung; Huang, Xuemei; Sinha, Rashmi; Freedman, Neal D.; Hollenbeck, Albert R.; Blair, Aaron; Chen, Honglei

2012-01-01

The authors prospectively examined whether caffeine intake was associated with lower risk of Parkinson disease (PD) in both men and women among 304,980 participants in the National Institutes of Health-AARP Diet and Health Study and whether smoking affected this relation. Multivariate odds ratios and 95% confidence intervals were derived from logistic regression models. Higher caffeine intake as assessed in 1995–1996 was monotonically associated with lower PD risk (diagnosed in 2000–2006) in both men and women. After adjustment for age, race, and physical activity, the odds ratio comparing the highest quintile of caffeine intake with the lowest was 0.75 (95% confidence interval: 0.60, 0.94; Ptrend = 0.005) for men and 0.60 (95% confidence interval: 0.39, 0.91; Ptrend = 0.005) for women. Further adjustment for duration of smoking and analyses carried out among never smokers showed similar results. A joint analysis with smoking suggested that smoking and caffeine may act independently in relation to PD risk. Finally, the authors conducted a meta-analysis of prospective studies and confirmed that caffeine intake was inversely associated with PD risk in both men and women. These findings suggest no gender difference in the relation between caffeine and PD. PMID:22505763

Maternal caffeine intake during pregnancy and childhood growth and overweight: results from a large Norwegian prospective observational cohort study.

Science.gov (United States)

Papadopoulou, Eleni; Botton, Jérémie; Brantsæter, Anne-Lise; Haugen, Margaretha; Alexander, Jan; Meltzer, Helle Margrete; Bacelis, Jonas; Elfvin, Anders; Jacobsson, Bo; Sengpiel, Verena

2018-04-23

To study the association between maternal caffeine intake during pregnancy and the child's weight gain and overweight risk up to 8 years. Prospective nationwide pregnancy cohort. The Norwegian Mother and Child Cohort Study. A total of 50 943 mothers recruited from 2002 to 2008 and their children, after singleton pregnancies, with information about average caffeine intake assessed at mid-pregnancy. Child's body size information at 11 age points from 6 weeks to 8 years. We defined excess growth in infancy as a WHO weight gain z-score of >0.67 from birth to age 1 year, and overweight according to the International Obesity Task Force. We used a growth model to assess individual growth trajectories. Compared with pregnant women with low caffeine intake (200 mg/day had consistently higher weight. Very high caffeine exposures were associated with higher weight gain velocity from infancy to age 8 years. Any caffeine consumption during pregnancy is associated with a higher risk of excess infant growth and of childhood overweight, mainly at preschool ages. Maternal caffeine intake may modify the overall weight growth trajectory of the child from birth to 8 years. This study adds supporting evidence for the current advice to reduce caffeine intake during pregnancy. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Maternal caffeine intake during pregnancy is associated with birth weight but not with gestational length: results from a large prospective observational cohort study

Science.gov (United States)

2013-01-01

Background Pregnant women consume caffeine daily. The aim of this study was to examine the association between maternal caffeine intake from different sources and (a) gestational length, particularly the risk for spontaneous preterm delivery (PTD), and (b) birth weight (BW) and the baby being small for gestational age (SGA). Methods This study is based on the Norwegian Mother and Child Cohort Study conducted by the Norwegian Institute of Public Health. A total of 59,123 women with uncomplicated pregnancies giving birth to a live singleton were identified. Caffeine intake from different sources was self-reported at gestational weeks 17, 22 and 30. Spontaneous PTD was defined as spontaneous onset of delivery between 22+0 and 36+6 weeks (n = 1,451). As there is no consensus, SGA was defined according to ultrasound-based (Marsal, n = 856), population-based (Skjaerven, n = 4,503) and customized (Gardosi, n = 4,733) growth curves. Results The main caffeine source was coffee, but tea and chocolate were the main sources in women with low caffeine intake. Median pre-pregnancy caffeine intake was 126 mg/day (IQR 40 to 254), 44 mg/day (13 to 104) at gestational week 17 and 62 mg/day (21 to 130) at gestational week 30. Coffee caffeine, but not caffeine from other sources, was associated with prolonged gestation (8 h/100 mg/day, P caffeine was associated with spontaneous PTD risk. Caffeine intake from different sources, measured repeatedly during pregnancy, was associated with lower BW (Marsal-28 g, Skjaerven-25 g, Gardosi-21 g per 100 mg/day additional total caffeine for a baby with expected BW 3,600 g, P Caffeine intake of 200 to 300 mg/day increased the odds for SGA (OR Marsal 1.62, Skjaerven 1.44, Gardosi 1.27, P caffeine, consumption was associated with marginally increased gestational length but not with spontaneous PTD risk. Caffeine intake was consistently associated with decreased BW and increased odds of SGA. The association was strengthened by concordant results for

Caffeinated beverage intake and reproductive hormones among premenopausal women in the BioCycle Study123

Science.gov (United States)

Schisterman, Enrique F; Mumford, Sunni L; Pollack, Anna Z; Zhang, Cuilin; Ye, Aijun; Stanford, Joseph B; Hammoud, Ahmad O; Porucznik, Christina A; Wactawski-Wende, Jean

2012-01-01

Background: Caffeinated beverages are widely consumed among women of reproductive age, but their association with reproductive hormones, and whether race modifies any such associations, is not well understood. Objective: We assessed the relation between caffeine and caffeinated beverage intake and reproductive hormones in healthy premenopausal women and evaluated the potential effect modification by race. Design: Participants (n = 259) were followed for up to 2 menstrual cycles and provided fasting blood specimens for hormonal assessment at up to 8 visits per cycle and four 24-h dietary recalls per cycle. Weighted linear mixed models and nonlinear mixed models with harmonic terms were used to estimate associations between caffeine and hormone concentrations, adjusted for age, adiposity, physical activity, energy and alcohol intakes, and perceived stress. On the basis of a priori assumptions, an interaction between race and caffeine was tested, and stratified results are presented. Results: Caffeine intake ≥200 mg/d was inversely associated with free estradiol concentrations among white women (β = −0.15; 95% CI: −0.26, −0.05) and positively associated among Asian women (β = 0.61; 95% CI: 0.31, 0.92). Caffeinated soda intake and green tea intake ≥1 cup/d (1 cup = 240 mL) were positively associated with free estradiol concentrations among all races: β = 0.14 (95% CI: 0.06, 0.22) and β = 0.26 (95% CI: 0.07, 0.45), respectively. Conclusions: Moderate consumption of caffeine was associated with reduced estradiol concentrations among white women, whereas caffeinated soda and green tea intakes were associated with increased estradiol concentrations among all races. Further research is warranted on the association between caffeine and caffeinated beverages and reproductive hormones and whether these relations differ by race. PMID:22237060

Caffeine intake is associated with pupil dilation and enhanced accommodation.

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Abokyi, S; Owusu-Mensah, J; Osei, K A

2017-04-01

PurposeIt is purported that caffeine, an autonomic stimulant, affects visual performance. This study sought to assess whether caffeine intake was associated with changes in pupil size and/or amplitude of accommodation.Patients and methodsA double-masked, crossover study was conducted in 50 healthy subjects of age range 19 to 25 years. Subjects were randomized to treatments such that subjects consumed either 250 mg caffeine drink or vehicle on separate days. Amplitude of accommodation was measured by the push-up technique, and pupil size using a millimeter ruler fixed to a slit lamp biomicroscope in dim illumination (5 lux). Amplitude of accommodation and pupil size were taken at baseline, and at 30, 60 and 90 min time points post treatment. Repeated measures one-way ANOVA and paired t-test were used in analyzing data.ResultsAmplitude of accommodation and pupil size after caffeine intake were significantly greater than vehicle (Pcaffeine beverage was associated with significant increases in amplitude of accommodation and pupil size with time (Pcaffeine. This study suggests caffeine may have some influence on visual functions.

Caffeine and cardiovascular health.

Science.gov (United States)

Turnbull, Duncan; Rodricks, Joseph V; Mariano, Gregory F; Chowdhury, Farah

2017-10-01

This report evaluates the scientific literature on caffeine with respect to potential cardiovascular outcomes, specifically relative risks of total cardiovascular disease (CVD), coronary heart disease (CHD) and acute myocardial infarction (AMI), effects on arrhythmia, heart failure, sudden cardiac arrest, stroke, blood pressure, hypertension, and other biomarkers of effect, including heart rate, cerebral blood flow, cardiac output, plasma homocysteine levels, serum cholesterol levels, electrocardiogram (EKG) parameters, heart rate variability, endothelial/platelet function and plasma/urine catecholamine levels. Caffeine intake has been associated with a range of reversible and transient physiological effects broadly and cardiovascular effects specifically. This report attempts to understand where the delineations exist in caffeine intake and corresponding cardiovascular effects among various subpopulations. The available literature suggests that cardiovascular effects experienced by caffeine consumers at levels up to 600 mg/day are in most cases mild, transient, and reversible, with no lasting adverse effect. The point at which caffeine intake may cause harm to the cardiovascular system is not readily identifiable in part because data on the effects of daily intakes greater than 600 mg is limited. However, the evidence considered within this review suggests that typical moderate caffeine intake is not associated with increased risks of total cardiovascular disease; arrhythmia; heart failure; blood pressure changes among regular coffee drinkers; or hypertension in baseline populations. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Effect of different protocols of caffeine intake on metabolism and endurance performance.

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Cox, Gregory R; Desbrow, Ben; Montgomery, Paul G; Anderson, Megan E; Bruce, Clinton R; Macrides, Theodore A; Martin, David T; Moquin, Angela; Roberts, Alan; Hawley, John A; Burke, Louise M

2002-09-01

Competitive athletes completed two studies of 2-h steady-state (SS) cycling at 70% peak O(2) uptake followed by 7 kJ/kg time trial (TT) with carbohydrate (CHO) intake before (2 g/kg) and during (6% CHO drink) exercise. In Study A, 12 subjects received either 6 mg/kg caffeine 1 h preexercise (Precaf), 6 x 1 mg/kg caffeine every 20 min throughout SS (Durcaf), 2 x 5 ml/kg Coca-Cola between 100 and 120 min SS and during TT (Coke), or placebo. Improvements in TT were as follows: Precaf, 3.4% (0.2-6.5%, 95% confidence interval); Durcaf, 3.1% (-0.1-6.5%); and Coke, 3.1% (-0.2-6.2%). In Study B, eight subjects received 3 x 5 ml/kg of different cola drinks during the last 40 min of SS and TT: decaffeinated, 6% CHO (control); caffeinated, 6% CHO; decaffeinated, 11% CHO; and caffeinated, 11% CHO (Coke). Coke enhanced TT by 3.3% (0.8-5.9%), with all trials showing 2.2% TT enhancement (0.5-3.8%; P < 0.05) due to caffeine. Overall, 1) 6 mg/kg caffeine enhanced TT performance independent of timing of intake and 2) replacing sports drink with Coca-Cola during the latter stages of exercise was equally effective in enhancing endurance performance, primarily due to low intake of caffeine (approximately 1.5 mg/kg).

Does caffeine and alcohol intake before pregnancy predict the occurrence of spontaneous abortion?

DEFF Research Database (Denmark)

Tolstrup, J S; Kjær, S. K.; Munk, C

2003-01-01

BACKGROUND: Consumption of caffeine and alcohol is suspected to affect pregnancy outcome. Use of both stimulants is widespread and even minor effects on fetal viability are of public health interest. METHODS: We performed a nested case-control study using prospective data from a population.......72 (1.00-2.96) for a pre-pregnancy intake on 75-300, 301-500, 501-900 and >900 mg caffeine per day respectively (P = 0.05 for trend). A pre-pregnancy intake of alcohol was not a predictor for spontaneous abortion. CONCLUSIONS: A high intake of caffeine prior to pregnancy seems to be associated......-based cohort comprising 11088 women aged 20-29 years. From this cohort, women who experienced either a spontaneous abortion (n = 303) or who gave birth (n = 1381) during follow-up [mean time: 2.1 years (range: 1.6-3.4)] were selected. Associations between self-reported exposures to caffeine and/or alcohol...

Role of Caffeine Intake on Erectile Dysfunction in US Men: Results from NHANES 2001-2004.

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David S Lopez

Full Text Available Caffeine is consumed by more than 85% of adults and little is known about its role on erectile dysfunction (ED in population-based studies. We investigated the association of caffeine intake and caffeinated beverages with ED, and whether these associations vary among comorbidities for ED.Data were analyzed for 3724 men (≥20 years old who participated in the National Health and Nutrition Examination Survey (NHANES. ED was assessed by a single question during a self-paced, computer-assisted self-interview. We analyzed 24-h dietary recall data to estimate caffeine intake (mg/day. Multivariable logistic regression analyses using appropriate sampling weights were conducted.We found that men in the 3rd (85-170 mg/day and 4th (171-303 mg/day quintiles of caffeine intake were less likely to report ED compared to men in the lowest 1st quintile (0-7 mg/day [OR: 0.58; 95% CI, 0.37-0.89; and OR: 0.61; 95% CI, 0.38-0.97, respectively], but no evidence for a trend. Similarly, among overweight/obese and hypertensive men, there was an inverse association between higher quintiles of caffeine intake and ED compared to men in the lowest 1st quintile, P≤0.05 for each quintile. However, only among men without diabetes we found a similar inverse association (Ptrend = 0.01.Caffeine intake reduced the odds of prevalent ED, especially an intake equivalent to approximately 2-3 daily cups of coffee (170-375 mg/day. This reduction was also observed among overweight/obese and hypertensive, but not among diabetic men. Yet, these associations are warranted to be investigated in prospective studies.

Caffeine Intake During Pregnancy and Risk of Problem Behavior in 5- to 6-Year-Old Children

NARCIS (Netherlands)

Loomans, Eva M.; Hofland, Laura; van der Stelt, Odin; van der Wal, Marcel F.; Koot, Hans M.; van den Bergh, Bea R. H.; Vrijkotte, Tanja G. M.

2012-01-01

BACKGROUND AND OBJECTIVE: Human studies that have investigated the association between caffeine intake during pregnancy and offspring's behavioral outcomes are scant and inconclusive. We prospectively investigated the association between maternal caffeine intake during pregnancy and children's

Caffeine intake during pregnancy and risk of problem behavior in 5- to 6-year-old children

NARCIS (Netherlands)

Loomans, E.M.; Hofland, L.; van der Stelt, O.; van der Wal, M.F.; Koot, H.M.; Van den Bergh, B.R.H.; Vrijkotte, T.G.M.

2012-01-01

BACKGROUND AND OBJECTIVE: Human studies that have investigated the association between caffeine intake during pregnancy and offspring's behavioral outcomes are scant and inconclusive. We prospectively investigated the association between maternal caffeine intake during pregnancy and children's

A case-control field study on the relationships among type 2 diabetes, sleepiness and habitual caffeine intake.

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Urry, Emily; Jetter, Alexander; Holst, Sebastian C; Berger, Wolfgang; Spinas, Giatgen A; Langhans, Wolfgang; Landolt, Hans-Peter

2017-02-01

The purpose of this study was to examine the possible links between type 2 diabetes, daytime sleepiness, sleep quality and caffeine consumption. In this case-control field study, comparing type 2 diabetic ( n=134) and non-type 2 diabetic ( n=230) participants, subjects completed detailed and validated questionnaires to assess demographic status, health, daytime sleepiness, sleep quality and timing, diurnal preference, mistimed circadian rhythms and habitual caffeine intake. All participants gave saliva under standardised conditions for CYP1A2 genotyping and quantification of caffeine concentration. Hierarchical linear regression analyses examined whether type 2 diabetes status was associated with caffeine consumption. Type 2 diabetic participants reported greater daytime sleepiness ( p=0.001), a higher prevalence of sleep apnoea ( p=0.005) and napping ( p=0.008), and greater habitual caffeine intake ( pcaffeine concentration at bedtime ( p=0.01). Multiple regression analyses revealed that type 2 diabetes status was associated with higher self-reported caffeine consumption ( pcaffeine ( pcaffeine intake. Subjective sleep and circadian estimates were similar between case and control groups. Type 2 diabetic patients may self-medicate with caffeine to alleviate daytime sleepiness. High caffeine intake reflects a lifestyle factor that may be considered when promoting type 2 diabetes management.

Parkinson's disease risks associated with cigarette smoking, alcohol consumption, and caffeine intake.

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Checkoway, Harvey; Powers, Karen; Smith-Weller, Terri; Franklin, Gary M; Longstreth, W T; Swanson, Phillip D

2002-04-15

A reduced risk for Parkinson's disease (PD) among cigarette smokers has been observed consistently during the past 30 years. Recent evidence suggests that caffeine may also be protective. Findings are presented regarding associations of PD with smoking, caffeine intake, and alcohol consumption from a case-control study conducted in western Washington State in 1992-2000. Incident PD cases (n = 210) and controls (n = 347), frequency matched on gender and age were identified from enrollees of the Group Health Cooperative health maintenance organization. Exposure data were obtained by in-person questionnaires. Ever having smoked cigarettes was associated with a reduced risk of PD (odds ratio (OR) = 0.5, 95% confidence interval (CI): 0.4, 0.8). A stronger relation was found among current smokers (OR = 0.3, 95% CI: 0.1, 0.7) than among ex-smokers (OR = 0.6, 95% CI: 0.4, 0.9), and there was an inverse gradient with pack-years smoked (trend p coffee consumption or total caffeine intake or for alcohol consumption. However, reduced risks were observed for consumption of 2 cups/day or more of tea (OR = 0.4, 95% CI: 0.2, 0.9) and two or more cola drinks/day (OR = 0.6, 95% CI: 0.3, 1.4). The associations for tea and cola drinks were not confounded by smoking or coffee consumption.

Caffeine intake is not associated with serum testosterone levels in adult men: cross-sectional findings from the NHANES 1999-2004 and 2011-2012.

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Lopez, David S; Advani, Shailesh; Qiu, Xueting; Tsilidis, Konstantinos K; Khera, Mohit; Kim, Jeri; Canfield, Steven

2018-04-25

The association of caffeine intake with testosterone remains unclear. We evaluated the association of caffeine intake with serum testosterone among American men and determined whether this association varied by race/ethnicity and measurements of adiposity. Data were analyzed for 2581 men (≥20 years old) who participated in the cycles of the NHANES 1999-2004 and 2011-2012, a cross-sectional study. Testosterone (ng/mL) was measured by immunoassay among men who participated in the morning examination session. We analyzed 24-h dietary recall data to estimate caffeine intake (mg/day). Multivariable weighted linear regression models were conducted. We identified no linear relationship between caffeine intake and testosterone levels in the total population, but there was a non-linear association (p nonlinearity  < .01). Similarly, stratified analysis showed nonlinear associations among Mexican-American and Non-Hispanic White men (p nonlinearity  ≤ .03 both) and only among men with waist circumference <102 cm and body mass index <25 kg/m 2 (p nonlinearity  < .01, both). No linear association was identified between levels of caffeine intake and testosterone in US men, but we observed a non-linear association, including among racial/ethnic groups and measurements of adiposity in this cross-sectional study. These associations are warranted to be investigated in larger prospective studies.

Nutrition Influences Caffeine-Mediated Sleep Loss in Drosophila.

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Keebaugh, Erin S; Park, Jin Hong; Su, Chenchen; Yamada, Ryuichi; Ja, William W

2017-11-01

Plant-derived caffeine is regarded as a defensive compound produced to prevent herbivory. Caffeine is generally repellent to insects and often used to study the neurological basis for aversive responses in the model insect, Drosophila melanogaster. Caffeine is also studied for its stimulatory properties where sleep or drowsiness is suppressed across a range of species. Since limiting access to food also inhibits fly sleep-an effect known as starvation-induced sleep suppression-we tested whether aversion to caffeinated food results in reduced nutrient intake and assessed how this might influence fly studies on the stimulatory effects of caffeine. We measured sleep and total consumption during the first 24 hours of exposure to caffeinated diets containing a range of sucrose concentrations to determine the relative influence of caffeine and nutrient ingestion on sleep. Experiments were replicated using three fly strains. Caffeine reduced total consumption and nighttime sleep, but only at intermediate sucrose concentrations. Although sleep can be modeled by an exponential dose response to nutrient intake, caffeine-mediated sleep loss cannot be explained by absolute caffeine or sucrose ingestion alone. Instead, reduced sleep strongly correlates with changes in total consumption due to caffeine. Other bitter compounds phenocopy the effect of caffeine on sleep and food intake. Our results suggest that a major effect of dietary caffeine is on fly feeding behavior. Changes in feeding behavior may drive caffeine-mediated sleep loss. Future studies using psychoactive compounds should consider the potential impact of nutrition when investigating effects on sleep. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Effect of caffeine intake on critical power model parameters determined on a cycle ergometer

Directory of Open Access Journals (Sweden)

Marcus Vinicius Machado

2010-01-01

Full Text Available The aim of this study was to evaluate the effect of caffeine intake on critical power model parameters determined on a cycle ergometer. Eight male subjects participated in this study. A double-blind protocol consisting of the intake of pure caffeine (6 mg/kg or placebo (maltodextrin 60 min before testing was used. Subjects were submitted to four constant-load tests on a cycle ergometer. These tests were conducted randomly in the caffeine and placebo groups [checar] at intensities of 80, 90, 100 and 110% maximum power at a rate of 70 rpm until exhaustion to determine the critical power. As a criterion for stopping the test was adopted any rate fall without recovery by more than five seconds. The critical power and anaerobic work capacity were obtained by nonlinear regression and fitting of the curve to a hyperbolic power-time model. The Shapiro-Wilk test and paired Student t-test were used for statistical analysis. No significant differences in critical power were observed between the caffeine and placebo groups (192.9 ± 31.3 vs 197.7 ± 29.4 W, respectively. The anaerobic work capacity was significantly higher in the caffeine group (20.1 ± 5.2 vs 16.3 ± 4.2 W, p< 0.01. A high association (r2 was observed between the caffeine and placebo conditions (0.98 ± 0.02 and 0.99 ± 0.0, respectively. We conclude that caffeine intake did not improve critical power performance but increased anaerobic work capacity by influencing performance at loads of higher intensity and shorter duration.

Relationships Between Caffeine Intake and Risk for Probable Dementia or Global Cognitive Impairment: The Women's Health Initiative Memory Study.

Science.gov (United States)

Driscoll, Ira; Shumaker, Sally A; Snively, Beverly M; Margolis, Karen L; Manson, JoAnn E; Vitolins, Mara Z; Rossom, Rebecca C; Espeland, Mark A

2016-12-01

Nonhuman studies suggest a protective effect of caffeine on cognition. Although human literature remains less consistent, reviews suggest a possible favorable relationship between caffeine consumption and cognitive impairment or dementia. We investigated the relationship between caffeine intake and incidence of cognitive impairment or probable dementia in women aged 65 and older from the Women's Health Initiative Memory Study. All women with self-reported caffeine consumption at enrollment were included (N = 6,467). In 10 years or less of follow-up with annual assessments of cognitive function, 388 of these women received a diagnosis of probable dementia based on a 4-phase protocol that included central adjudication. We used proportional hazards regression to assess differences in the distributions of times until incidence of probable dementia or composite cognitive impairment among women grouped by baseline level of caffeine intake, adjusting for risk factors (hormone therapy, age, race, education, body mass index, sleep quality, depression, hypertension, prior cardiovascular disease, diabetes, smoking, and alcohol consumption). Women consuming above median levels (mean intake = 261mg) of caffeine intake for this group were less likely to develop incident dementia (hazard ratio = 0.74, 95% confidence interval [0.56, 0.99], p = .04) or any cognitive impairment (hazard ratio = 0.74, confidence interval [0.60, 0.91], p = .005) compared to those consuming below median amounts (mean intake = 64mg) of caffeine for this group. Our findings suggest lower odds of probable dementia or cognitive impairment in older women whose caffeine consumption was above median for this group and are consistent with the existing literature showing an inverse association between caffeine intake and age-related cognitive impairment. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e

Relationships Between Caffeine Intake and Risk for Probable Dementia or Global Cognitive Impairment: The Women’s Health Initiative Memory Study

Science.gov (United States)

Shumaker, Sally A.; Snively, Beverly M.; Margolis, Karen L.; Manson, JoAnn E.; Vitolins, Mara Z.; Rossom, Rebecca C.; Espeland, Mark A.

2016-01-01

Background: Nonhuman studies suggest a protective effect of caffeine on cognition. Although human literature remains less consistent, reviews suggest a possible favorable relationship between caffeine consumption and cognitive impairment or dementia. We investigated the relationship between caffeine intake and incidence of cognitive impairment or probable dementia in women aged 65 and older from the Women’s Health Initiative Memory Study. Methods: All women with self-reported caffeine consumption at enrollment were included (N = 6,467). In 10 years or less of follow-up with annual assessments of cognitive function, 388 of these women received a diagnosis of probable dementia based on a 4-phase protocol that included central adjudication. We used proportional hazards regression to assess differences in the distributions of times until incidence of probable dementia or composite cognitive impairment among women grouped by baseline level of caffeine intake, adjusting for risk factors (hormone therapy, age, race, education, body mass index, sleep quality, depression, hypertension, prior cardiovascular disease, diabetes, smoking, and alcohol consumption). Results: Women consuming above median levels (mean intake = 261mg) of caffeine intake for this group were less likely to develop incident dementia (hazard ratio = 0.74, 95% confidence interval [0.56, 0.99], p = .04) or any cognitive impairment (hazard ratio = 0.74, confidence interval [0.60, 0.91], p = .005) compared to those consuming below median amounts (mean intake = 64mg) of caffeine for this group. Conclusion: Our findings suggest lower odds of probable dementia or cognitive impairment in older women whose caffeine consumption was above median for this group and are consistent with the existing literature showing an inverse association between caffeine intake and age-related cognitive impairment. PMID:27678290

Stimulation of Intestinal Cl- Secretion Through CFTR by Caffeine Intake in Salt-Sensitive Hypertensive Rats

Directory of Open Access Journals (Sweden)

Xiao Wei

2018-03-01

Full Text Available Background/Aims: High salt consumption is a major risk factor for hypertension, and sodium homeostasis is regulated by both intestinal sodium absorption and urinary sodium excretion. Chronic caffeine intake has been reported to attenuate salt-sensitive hypertension by promoting urinary sodium excretion; however, its exact role in intestinal sodium absorption remains unknown. Here, we investigated whether and how chronic caffeine consumption antagonizes salt-sensitive hypertension by inhibiting intestinal sodium absorption. Methods: Dahl salt-sensitive rats were fed 8% NaCl chow and 0.1% caffeine in their drinking water for 15 days. The blood pressure and fecal sodium content were measured. The effect of caffeine on the movement of Cl- in enterocyte cells was determined with the Ussing chamber assay. Results: Rats that were treated with caffeine displayed significantly lower mean blood pressure and higher fecal sodium content than the controls. Consistent with these findings, caffeine intake decreased fluid absorption by the intestine in the fluid perfusion experiment. Further, the results from the Ussing chamber assay indicated that caffeine promoted Cl- secretion through enterocyte apical cystic fibrosis transmembrane conductance regulator (CFTR, and thus inhibited sodium absorption. Moreover, depletion of cAMP or inhibition of CFTR completely abolished the effect of caffeine on Cl- secretion. Conclusion: The results indicate that chronic caffeine consumption reduces sodium absorption by promoting CFTR-mediated Cl- secretion in the intestine, which contributes to the anti-hypertensive effect of caffeine in salt-sensitive rats.

Estimation of caffeine intake in Japanese adults using 16 d weighed diet records based on a food composition database newly developed for Japanese populations.

Science.gov (United States)

Yamada, Mai; Sasaki, Satoshi; Murakami, Kentaro; Takahashi, Yoshiko; Okubo, Hitomi; Hirota, Naoko; Notsu, Akiko; Todoriki, Hidemi; Miura, Ayako; Fukui, Mitsuru; Date, Chigusa

2010-05-01

Previous studies in Western populations have linked caffeine intake with health status. While detailed dietary assessment studies in these populations have shown that the main contributors to caffeine intake are coffee and tea, the wide consumption of Japanese and Chinese teas in Japan suggests that sources of intake in Japan may differ from those in Western populations. Among these teas, moreover, caffeine content varies widely among the different forms consumed (brewed, canned or bottled), suggesting the need for detailed dietary assessment in estimating intake in Japanese populations. Here, because a caffeine composition database or data obtained from detailed dietary assessment have not been available, we developed a database for caffeine content in Japanese foods and beverages, and then used it to estimate intake in a Japanese population. The caffeine food composition database was developed using analytic values from the literature, 16 d weighed diet records were collected, and caffeine intake was estimated from the 16 d weighed diet records. Four areas in Japan, Osaka (Osaka City), Okinawa (Ginowan City), Nagano (Matsumoto City) and Tottori (Kurayoshi City), between November 2002 and September 2003. Two hundred and thirty Japanese adults aged 30-69 years. Mean caffeine intake was 256.2 mg/d for women and 268.3 mg/d for men. The major contributors to intake were Japanese and Chinese teas and coffee (47 % each). Caffeine intake above 400 mg/d, suggested in reviews to possibly have negative health effects, was seen in 11 % of women and 15 % of men. In this Japanese population, caffeine intake was comparable to the estimated values reported in Western populations.

Caffeine-containing beverages, total fluid consumption, and premenstrual syndrome.

Science.gov (United States)

Rossignol, A M; Bonnlander, H

1990-09-01

The main objective of this study was to evaluate whether daily consumption of caffeine-containing beverages is related to the prevalence and severity of premenstrual syndrome apart from any effects of daily total fluid consumption. A secondary objective was to determine whether daily total fluid consumption itself is related to premenstrual syndrome. The study is based on 841 responses to a questionnaire probing menstrual and premenstrual health, and daily fluid consumption, which was mailed to female university students in Oregon. Analysis of the data revealed that consumption of caffeine-containing beverages was strongly related to the prevalence of premenstrual syndrome. Among women with more severe symptoms, the relation between consumption of caffeine-containing beverages and premenstrual syndrome was dose-dependent, with prevalence odds ratios equal to 1.3 for consumers of one cup of a caffeine-containing beverage per day and increasing steadily to 7.0 for consumers of eight to 10 cups per day. The effects were apparent among both caffeine-containing tea/coffee consumers and caffeine-containing soda consumers. The observed effects were only slightly reduced when daily total fluid consumption was controlled. Daily total fluid consumption also was related to the prevalence of premenstrual symptoms although the effects were large only for consumers of 13-19 cups of fluid per day (the largest amount studied).

Caffeine Intake from Food and Beverage Sources and Trends among Children and Adolescents in the United States: Review of National Quantitative Studies from 1999 to 201112345

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Ahluwalia, Namanjeet; Herrick, Kirsten

2015-01-01

There is increasing concern about potential adverse effects of caffeine in children. Our understanding of caffeine intake relies on studies dating to the late 1990s. This article synthesizes information from national studies since then to describe caffeine consumption, its association with sociodemographic factors, key dietary sources including caffeine-containing energy drinks (CCEDs), and trends in caffeine intake and sources among US children. Findings from the Kanter Worldpanel (KWP) Beverage Consumption Panel and the NHANES showed that caffeine consumption prevalence was generally consistent across studies and over time; more than one-half of 2- to 5-y-olds and ∼75% of older children (>5 y) consumed caffeine. The usual intakes of caffeine were 25 and 50 mg/d for children and adolescents aged 2–11 and 12–17 y, respectively (NHANES 2007–2010). Caffeine consumption correlated with age and was higher in non-Hispanic white children. The key sources of caffeine were soda and tea as well as flavored dairy (for children aged caffeine intake was noted in children overall during the 10- to 12-y period examined; intakes remained stable among older children (≥12 y). A significant increasing trend in CCED and coffee consumption and a decline in soda intake were noted (1999–2010). In 2009–2010, 10% of 12- to 19-y-olds and 10–25% of caffeine consumers (aged 12–19 y) had intakes exceeding Canadian maximal guidelines. Continued monitoring can help better understand changes in caffeine consumption patterns of youth. PMID:25593149

Serum caffeine and paraxanthine concentrations and menstrual cycle function: correlations with beverage intakes and associations with race, reproductive hormones, and anovulation in the BioCycle Study12

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Schisterman, Enrique F; Wactawski-Wende, Jean; Perkins, Neil J; Radin, Rose G; Zarek, Shvetha M; Mitchell, Emily M; Sjaarda, Lindsey A; Mumford, Sunni L

2016-01-01

Background: Clinicians often recommend limiting caffeine intake while attempting to conceive; however, few studies have evaluated the associations between caffeine exposure and menstrual cycle function, and we are aware of no previous studies assessing biological dose via well-timed serum measurements. Objectives: We assessed the relation between caffeine and its metabolites and reproductive hormones in a healthy premenopausal cohort and evaluated potential effect modification by race. Design: Participants (n = 259) were followed for ≤2 menstrual cycles and provided fasting blood specimens ≤8 times/cycle. Linear mixed models were used to estimate associations between serum caffeine biomarkers and geometric mean reproductive hormones, whereas Poisson regression was used to assess risk of sporadic anovulation. Results: The highest compared with the lowest serum caffeine tertile was associated with lower total testosterone [27.9 ng/dL (95% CI: 26.7, 29.0 ng/dL) compared with 29.1 ng/dL (95% CI: 27.9, 30.3 ng/dL), respectively] and free testosterone [0.178 ng/mL (95% CI: 0.171, 0.185 ng/dL) compared with 0.186 ng/mL (95% CI: 0.179, 0.194 ng/dL), respectively] after adjustment for age, race, percentage of body fat, daily vigorous exercise, perceived stress, depression, dietary factors, and alcohol intake. The highest tertiles compared with the lowest tertiles of caffeine and paraxanthine were also associated with reduced risk of anovulation [adjusted RRs (aRRs): 0.39 (95% CI: 0.18, 0.87) and 0.40 (95% CI: 0.18, 0.87), respectively]. Additional adjustment for self-reported coffee intake did not alter the reproductive hormone findings and only slightly attenuated the results for serum caffeine and paraxanthine and anovulation. Although reductions in the concentrations of total testosterone and free testosterone and decreased risk of anovulation were greatest in Asian women, there was no indication of effect modification by race. Conclusion: Caffeine intake

Total, caffeinated and decaffeinated coffee and tea intake and gastric cancer risk

DEFF Research Database (Denmark)

Sanikini, Harinakshi; Dik, Vincent K; Siersema, Peter D

2015-01-01

Prospective studies examining the association between coffee and tea consumption and gastric cancer risk have shown inconsistent results. We investigated the association between coffee (total, caffeinated and decaffeinated) and tea consumption and the risk of gastric cancer by anatomical site...... and histological type in the EPIC study. Coffee and tea consumption was assessed by dietary questionnaires at baseline. Adjusted hazard ratios (HRs) were calculated using Cox regression models. During 11.6 years of follow up, 683 gastric adenocarcinoma cases were identified among 477,312 participants. We found......) and tea (HR 0.81, 95%-CI: 0.59-1.09; quartile 4 vs. non/quartile 1). When stratified by anatomical site, we observed a significant positive association between gastric cardia cancer risk and total coffee consumption per increment of 100mL/day (HR 1.06, 95%-CI: 1.03-1.11). Similarly, a significant positive...

Consumo de cafeína e prematuridade Caffeine intake and prematurity

Directory of Open Access Journals (Sweden)

Rita Adriana Gomes de Souza

2005-10-01

during pregnancy, it is important to evaluate if the consumption of this substance is associated with a reduction in gestational age. This article examines current knowledge on caffeine intake during pregnancy, based on epidemiological studies evaluating the association between caffeine intake and prematurity, the sources of caffeine and its consumption during pregnancy, the biochemistry, physiopathology and biological plausibility of the association, and the main limitations of the studies on caffeine and prematurity.

Evidence of the Impact of Diet, Fluid Intake, Caffeine, Alcohol and Tobacco on Lower Urinary Tract Symptoms: A Systematic Review.

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Bradley, Catherine S; Erickson, Bradley A; Messersmith, Emily E; Pelletier-Cameron, Anne; Lai, H Henry; Kreder, Karl J; Yang, Claire C; Merion, Robert M; Bavendam, Tamara G; Kirkali, Ziya

2017-11-01

Diet, fluid intake and caffeine, alcohol and tobacco use may have effects on lower urinary tract symptoms. Constructive changes in these modifiable nonurological factors are suggested to improve lower urinary tract symptoms. To better understand the relationship between nonurological factors and lower urinary tract symptoms, we performed a systematic literature review to examine, grade and summarize reported associations between lower urinary tract symptoms and diet, fluid intake and caffeine, tobacco and alcohol use. We performed PubMed® searches for eligible articles providing evidence on associations between 1 or more nonurological factors and lower urinary tract symptoms. A modified Oxford scale was used to grade the evidence. We reviewed 111 articles addressing diet (28 studies), fluid intake (21) and caffeine (21), alcohol (26) and tobacco use (44). The evidence grade was generally low (6% level 1, 24% level 2, 11% level 3 and 59% level 4). Fluid intake and caffeine use were associated with urinary frequency and urgency in men and women. Modest alcohol use was associated with decreased likelihood of benign prostatic hyperplasia diagnosis and reduced lower urinary tract symptoms in men. Associations between lower urinary tract symptoms and ingestion of certain foods and tobacco were inconsistent. Evidence of associations between lower urinary tract symptoms and diet, fluid intake and caffeine, alcohol and tobacco use is sparse and mostly observational. However, there is evidence of associations between increased fluid and caffeine intake and urinary frequency/urgency, and between modest alcohol intake and decreased benign prostatic hyperplasia diagnosis and lower urinary tract symptoms. Given the importance of these nonurological factors in daily life, and their perceived impact on lower urinary tract symptoms, higher quality evidence is needed. Copyright © 2017 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All

Caffeine intake improves intense intermittent exercise performance and reduces muscle interstitial potassium accumulation

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Mohr, Magni; Nielsen, Jens Jung; Bangsbo, Jens

2011-01-01

The effect of oral caffeine ingestion on intense intermittent exercise performance and muscle interstitial ion concentrations was examined. The study consists of two studies (S1 and S2). In S1 twelve subjects completed the Yo-Yo intermittent recovery level 2 (Yo-Yo IR2) test with prior caffeine (6...... mg/kg b.w.; CAF) or placebo (PLA) intake. In S2 six subjects performed one low intense (20 W) and three intense (50 W) 3-min (separated by 5 min) one-legged knee-extension exercise bouts with (CAF) and without (CON) prior caffeine supplementation for determination of muscle interstitial K(+) and Na...

Dispelling the myth that habitual caffeine consumption influences the performance response to acute caffeine supplementation.

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Gonçalves, Lívia de Souza; Painelli, Vitor de Salles; Yamaguchi, Guilherme; Oliveira, Luana Farias de; Saunders, Bryan; da Silva, Rafael Pires; Maciel, Erika; Artioli, Guilherme Giannini; Roschel, Hamilton; Gualano, Bruno

2017-07-01

This study investigates the influence of habitual caffeine intake on aerobic exercise-performance responses to acute caffeine supplementation. A double-blind, crossover, counterbalanced study was performed. Forty male endurance-trained cyclists were allocated into tertiles, according to their daily caffeine intake: low (58 ± 29 mg/d), moderate (143 ± 25 mg/d), and high (351 ± 139 mg/d) consumers. Participants completed three trials in which they performed simulated cycling time trials (TTs) in the fastest time possible following ingestion of the following: caffeine (CAF: 6 mg/kg body mass), placebo (PLA), and no supplement (CON). A mixed-model analysis revealed that TT performance was significantly improved in CAF compared with PLA and CON (29.92 ± 2.18 vs. 30.81 ± 2.67 and 31.14 ± 2.71 min, respectively; P = 0.0002). Analysis of covariance revealed no influence of habitual caffeine intake as a covariate on exercise performance ( P = 0.47). TT performance was not significantly different among tertiles ( P = 0.75). No correlation was observed between habitual caffeine intake and absolute changes (CAF - CON) in TT performance with caffeine ( P = 0.524). Individual analysis showed that eight, seven, and five individuals improved above the variation of the test in CAF in the low, moderate, and high tertiles, respectively. A Fisher's exact test did not show any significant differences in the number of individuals who improved in CAF among the tertiles ( P > 0.05). Blood lactate and ratings of perceived exertion were not different between trials and tertiles ( P > 0.05). Performance effects of acute caffeine supplementation during an ~30-min cycling TT performance were not influenced by the level of habitual caffeine consumption. NEW & NOTEWORTHY There has been a long-standing paradigm that habitual caffeine intake may influence the ergogenicity of caffeine supplementation. Low, moderate, and high caffeine consumers showed similar absolute and

Determination of caffeine and identification of undeclared substances in dietary supplements and caffeine dietary exposure assessment.

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Neves, Diana Brito da Justa; Caldas, Eloisa Dutra

2017-07-01

Caffeine is one of the most consumed stimulants in the world, and is a frequent ingredient of dietary supplements. The aims of this work were to validate a GC-MS method for the quantitation of caffeine and identification of other substances in supplements, mainly weight loss products, and to estimate the caffeine intake by consumers. Sample preparation included extraction with chloroform:water in ultrasonic bath, centrifugation and analysis of the organic layer for caffeine quantitation, and extraction with methanol for identification of other substances. A total of 213 samples of 52 supplement products not registered in Brazil and seized by the Brazilian Federal Police were analyzed. From the 109 samples that declared the amount of caffeine present, 26.6% contained more than 120% of the specified content. Considering the maximum recommended dose stated on the product labels, the consumption of 47.9% of the samples would lead to a daily intake of caffeine above the safe limit of 400 mg. Undeclared drugs, including sibutramine, phenolphthalein, amphepramone and femproporex were found in 28 samples. These results show that consumers of dietary supplements should be aware that these products might contain caffeine at levels that could represent potential health risks, in addition to undeclared pharmaceutical drugs. Copyright © 2017 Elsevier Ltd. All rights reserved.

Association of sleep quality with watching TV, computer games and caffeine intake in adolescents of Minoodar district, Qazvin

OpenAIRE

A. Avani; Sh. Jalilolghadr; A. Barikani; A. Javadi; S. Shabbidar; M. Javadi

2015-01-01

Background: Insufficient sleep or poor sleep quality affect learning, memory and performance and cause behavioral disorders. Watching television (TV), using computer and internet, playing computer games, and caffeine intake are of factors affecting sleep quality. Objective: The aim of this study was to determine the association of sleep quality with watching TV, computer games and caffeine intake in adolescents of Minoodar district, Qazvin41T. Methods: This cross sectional study was con...

Total, caffeinated and decaffeinated coffee and tea intake and gastric cancer risk : Results from the EPIC cohort study

NARCIS (Netherlands)

Sanikini, Harinakshi; Dik, Vincent K.; Siersema, Peter D.; Bhoo-Pathy, Nirmala; Uiterwaal, Cuno S. P. M.; Peeters, Petra H. M.; Alez, Carlos A. Gonz; Zamora-Ros, Raul; Overvad, Kim; Nneland, Anne Tj; Roswall, Nina; Boutron-Ruault, Marie-Christine; Fagherazzi, Guy; Racine, Antoine; Kuehn, Tilman; Katzke, Verena; Boeing, Heiner; Trichopoulou, Antonia; Trichopoulos, Dimitrios; Lagiou, Pagona; Palli, Domenico; Grioni, Sara; Vineis, Paolo; Tumino, Rosario; Panico, Salvatore; Weiderpass, Elisabete; Skeie, Guri; Braaten, Tonje; Huerta, Jose Maria; Sanchez-Cantalejo, Emilio; Barricarte, Aurelio; Sonestedt, Emily; Wallstrom, Peter; Nilsson, Lena Maria; Johansson, Ingegerd; Bradbury, Kathryn E.; Khaw, Kay-Tee; Wareham, Nick; Huybrechts, Inge; Freisling, Heinz; Cross, Amanda J.; Riboli, Elio; Bueno-de-Mesquita, H. B(as)

2015-01-01

Prospective studies examining the association between coffee and tea consumption and gastric cancer risk have shown inconsistent results. We investigated the association between coffee (total, caffeinated and decaffeinated) and tea consumption and the risk of gastric cancer by anatomical site and

Caffeine Intake During Pregnancy in Different Intrauterine Environments and its Association with Infant Anthropometric Measurements at 3 and 6 Months of Age.

Science.gov (United States)

de Medeiros, Thamíris Santos; Bernardi, Juliana Rombaldi; de Brito, Mariana Lopes; Bosa, Vera Lucia; Goldani, Marcelo Zubaran; da Silva, Clécio Homrich

2017-06-01

Objective To investigate the association between maternal caffeine intake during pregnancy and infant anthropometric measurements at age 3 and 6 months. Methods Longitudinal observational study of mother-child pairs stratified into five groups: diabetic women (DM), hypertensive women (HYP), smoking mothers (SMO), mothers of infants small for gestational age (SGA), and controls (CTL). Pairs were recruited from three public hospitals in Porto Alegre, Brazil, from 2011 to 2015, using a convenience sampling strategy. The Food Frequency Questionnaire (FFQ) was administered on postpartum day 7 to evaluate maternal caffeine intake during pregnancy. The anthropometric measurements of interest (weight, length, and skinfold thickness) were assessed at birth and at age 3 and 6 months. Linear regression was used to analyze the interaction between caffeine intake and skinfold thickness. Results Overall, 272 mother-child pairs were investigated (41 DM, 26 HYP, 68 SMO, 25 SGA, and 112 CTL). There were no differences in anthropometric measurements between infants born to mothers who had and had not consumed caffeine during pregnancy (P > 0.05). Children of mothers in the DM group had the highest adjusted average skinfold thicknesses at 3 months. An interaction between maternal caffeine intake during pregnancy and the sum of skinfolds at age 3 months was found in the DM and CTL groups (P caffeine intake influenced infants skinfold thickness measurements at 3 months of age. This parameter was reduced in infants born to mothers with DM and increased in those born to healthy control mothers.

The association between pre-treatment maternal alcohol and caffeine intake and outcomes of assisted reproduction in a prospectively followed cohort.

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Abadia, L; Chiu, Y-H; Williams, P L; Toth, T L; Souter, I; Hauser, R; Chavarro, J E; Gaskins, A J

2017-09-01

Is pre-treatment alcohol and caffeine intake associated with infertility treatment outcomes among women undergoing ART? Low to moderate alcohol and caffeine intakes in the year prior to infertility treatment were not related to ART outcomes. Alcohol and caffeine intake have been found to be associated with infertility in some studies. Nevertheless, data on their relation with outcomes of infertility treatments are scarce and inconsistent. We included 300 women (493 ART cycles) from the Environment and Reproductive Health Study, an ongoing cohort study (2006-2016). Pre-treatment intakes of alcohol and caffeine were assessed retrospectively using a validated food frequency questionnaire. Intermediate and clinical endpoints of ART were abstracted from electronic medical records. Generalized linear mixed models with random intercepts to account for multiple ART cycles per woman were used to evaluate the association with ART outcomes adjusting for age, BMI, smoking status, infertility diagnosis, protocol type, race, dietary patterns, and calories, vitamin B12 and folate intake. Median (range) pre-treatment alcohol and caffeine intakes were 5.6 (0.0-85.8) g/day and 124.9 (0.3-642.2) mg/day, respectively. The adjusted percentage of initiated cycles resulting in live birth (95% CI) for women in increasing categories of pre-treatment alcohol intake was 34% (20, 52%) for non-consumers, 46% (36, 57%) for 0.1-6 g/day, 41% (29, 53%) for 6.1-12 g/day, 42% (31, 55%) for 12.1-24 g/day, and 41% (22, 63%) for >24 g/day (P, trend = 0.87). The adjusted percentage of cycles resulting in live birth (95% CI) for women in increasing categories of caffeine intake was 46% (36-57%) for 300 mg/day (P, trend = 0.34). When specific types of alcoholic and caffeinated beverages were evaluated, no relations with ART treatment outcomes were observed. Residual confounding by other diet and lifestyle factors cannot be ruled out owing to the observational nature of this study. It is also unclear how

Coffee for morning hunger pangs. An examination of coffee and caffeine on appetite, gastric emptying, and energy intake.

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Schubert, Matthew M; Grant, Gary; Horner, Katy; King, Neil; Leveritt, Michael; Sabapathy, Surendran; Desbrow, Ben

2014-12-01

Coffee is one of the most widely consumed beverages in the world and has a number of potential health benefits. Coffee may influence energy expenditure and energy intake, which in turn may affect body weight. However, the influence of coffee and its constituents - particularly caffeine - on appetite remains largely unexplored. The objective of this study was to examine the impact of coffee consumption (with and without caffeine) on appetite sensations, energy intake, gastric emptying, and plasma glucose between breakfast and lunch meals. In a double-blind, randomised crossover design. Participants (n = 12, 9 women; Mean ± SD age and BMI: 26.3 ± 6.3 y and 22.7 ± 2.2 kg•m⁻²) completed 4 trials: placebo (PLA), decaffeinated coffee (DECAF), caffeine (CAF), and caffeine with decaffeinated coffee (COF). Participants were given a standardised breakfast labelled with ¹³C-octanoic acid and 225 mL of treatment beverage and a capsule containing either caffeine or placebo. Two hours later, another 225 mL of the treatment beverage and capsule was administered. Four and a half hours after breakfast, participants were given access to an ad libitum meal for determination of energy intake. Between meals, participants provided exhaled breath samples for determination of gastric emptying; venous blood and appetite sensations. Energy intake was not significantly different between the trials (Means ± SD, p> 0.05; Placebo: 2118 ± 663 kJ; Decaf: 2128 ± 739 kJ; Caffeine: 2287 ± 649 kJ; Coffee: 2016 ± 750 kJ); Other than main effects of time (p appetite sensations or plasma glucose between treatments (p > 0.05). Gastric emptying was not significantly different across trials (p > 0.05). No significant effects of decaffeinated coffee, caffeine or their combination were detected. However, the consumption of caffeine and/or coffee for regulation of energy balance over longer periods of time warrant further

Caffeine and exercise.

Science.gov (United States)

Paluska, Scott A

2003-08-01

Caffeine is the most commonly consumed drug in the world, and athletes frequently use it as an ergogenic aid. It improves performance and endurance during prolonged, exhaustive exercise. To a lesser degree it also enhances short-term, high-intensity athletic performance. Caffeine improves concentration, reduces fatigue, and enhances alertness. Habitual intake does not diminish caffeine's ergogenic properties. Several mechanisms have been proposed to explain the physiologic effects of caffeine, but adenosine receptor antagonism most likely accounts for the primary mode of action. It is relatively safe and has no known negative performance effects, nor does it cause significant dehydration or electrolyte imbalance during exercise. Routine caffeine consumption may cause tolerance or dependence, and abrupt discontinuation produces irritability, mood shifts, headache, drowsiness, or fatigue. Major sport governing bodies ban excessive use of caffeine, but current monitoring techniques are inadequate, and ethical dilemmas persist regarding caffeine intake by athletes.

Higher Caffeinated Coffee Intake Is Associated with Reduced Malignant Melanoma Risk: A Meta-Analysis Study.

Directory of Open Access Journals (Sweden)

Jibin Liu

Full Text Available Several epidemiological studies have determined the associations between coffee intake level and skin cancer risk; however, the results were not yet conclusive. Herein, we conducted a systematic review and meta-analysis of the cohort and case-control studies for the association between coffee intake level and malignant melanoma (MM risk.Studies were identified through searching the PubMed and MEDLINE databases (to November, 2015. Study-specific risk estimates were pooled under the random-effects model.Two case-control studies (846 MM patients and 843 controls and five cohort studies (including 844,246 participants and 5,737 MM cases were identified. For caffeinated coffee, the pooled relative risk (RR of MM was 0.81 [95% confidential interval (95% CI = 0.68-0.97; P-value for Q-test = 0.003; I2 = 63.5%] for those with highest versus lowest quantity of intake. In the dose-response analysis, the RR of MM was 0.955 (95% CI = 0.912-0.999 for per 1 cup/day increment of caffeinated coffee consumption and linearity dose-response association was found (P-value for nonlinearity = 0.326. Strikingly, no significant association was found between the decaffeinated coffee intake level and MM risk (pooled RR = 0.92, 95% CI = 0.81-1.05; P-value for Q-test = 0.967; I2 = 0%; highest versus lowest quantity of intake.This meta-analysis suggested that caffeinated coffee might have chemo-preventive effects against MM but not decaffeinated coffee. However, larger prospective studies and the intervention studies are warranted to confirm these findings.

Caffeine consumption and self-assessed stress, anxiety, and depression in secondary school children

Science.gov (United States)

Richards, Gareth; Smith, Andrew

2015-01-01

Previous research suggests that effects of caffeine on behaviour are positive unless one is investigating sensitive groups or ingestion of large amounts. Children are a potentially sensitive subgroup, and especially so considering the high levels of caffeine currently found in energy drinks. The present study used data from the Cornish Academies Project to investigate associations between caffeine (both its total consumption, and that derived separately from energy drinks, cola, tea, and coffee) and single-item measures of stress, anxiety, and depression, in a large cohort of secondary school children from the South West of England. After adjusting for additional dietary, demographic, and lifestyle covariates, positive associations between total weekly caffeine intake and anxiety and depression remained significant, and the effects differed between males and females. Initially, effects were also observed in relation to caffeine consumed specifically from coffee. However, coffee was found to be the major contributor to high overall caffeine intake, providing explanation as to why effects relating to this source were also apparent. Findings from the current study increase our knowledge regarding associations between caffeine intake and stress, anxiety, and depression in secondary school children, though the cross-sectional nature of the research made it impossible to infer causality. PMID:26508718

Association of sleep quality with watching TV, computer games and caffeine intake in adolescents of Minoodar district, Qazvin

Directory of Open Access Journals (Sweden)

A. Avani

2015-12-01

Full Text Available Background: Insufficient sleep or poor sleep quality affect learning, memory and performance and cause behavioral disorders. Watching television (TV, using computer and internet, playing computer games, and caffeine intake are of factors affecting sleep quality. Objective: The aim of this study was to determine the association of sleep quality with watching TV, computer games and caffeine intake in adolescents of Minoodar district, Qazvin41T. Methods: This cross sectional study was conducted in 319 adolescents (10 to 18 years old that were selected by multistage cluster random sampling method during 2010-2011. Demographic data and data on duration of playing computer games and watching TV were collected. Food frequency questionnaire and BEARS questionnaire were completed. Data were analyzed using Chi-square test, logistic regression analysis and ANOVA. Findings:Mean age was15±2.43 years41T. Of 319 adolescents, 162 (50.8% were female41T. The duration of watching TV or video41T was not significantly different41T between boys and girls. The duration of playing computer or video games41T was statistically different41T between boys and girls. There was no correlation between sleep quality and duration of watching TV or videos in a day, duration of playing computer or video games in a day, and caffeine intake in adolescents. Conclusions: With regards to the results, it seems that there is no association between sleep quality and watching TV, playing computer games and caffeine intake.

Fewer but heavier caffeine consumers in schizophrenia: a case-control study.

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Gurpegui, Manuel; Aguilar, M Carmen; Martínez-Ortega, José M; Jurado, Dolores; Diaz, Francisco J; Quintana, Hernando M; de Leon, Jose

2006-09-01

According to the literature, there is an association between schizophrenia and caffeine consumption, but it is not clear whether schizophrenia is associated with either higher prevalence of daily caffeine intake or the amount consumed. In this study we compared our previously published schizophrenia patients (n=250) with a control sample (n=290) after controlling for demographic variables and tobacco and alcohol consumption. Current caffeine intake was less frequent in schizophrenia patients (59%, 147/250) than in controls (70%, 204/290). In the multivariate analyses, caffeine intake was less frequent at an older age and in schizophrenia patients, and more frequent in smokers and alcohol users. Among caffeine consumers, heavy caffeine intake (> or =200 mg/day) was significantly associated with schizophrenia (64%, 94/147 in schizophrenia versus 36%, 73/204 in controls), as well as older age and smoking. Daily amount of caffeine intake and smoked cigarettes correlated significantly in the schizophrenia group but not in the control group; the correlation of caffeine intake with nicotine dependence was low and non-significant in both groups. The association between current smoking and heavy caffeine intake may be partly explained by a pharmacokinetic effect: tobacco smoke compounds induce caffeine metabolism by the cytochrome P450 1A2. Although schizophrenia by itself may be associated with heavy caffeine intake in caffeine users, part of this association was explained by the association between schizophrenia and smoking. The relationship between caffeine and alcohol intake appeared to be more complex; alcohol and caffeine use were significantly associated, but within caffeine users alcohol was associated with less frequent heavy caffeine consumption among smokers. In future studies, the measurement of plasma caffeine levels will help both to better define heavy caffeine intake and to control for smoking pharmacokinetic effects.

Caffeine intake and abstract reasoning among 1374 unselected men and women from general population. Role of the -163C>A polymorphism of CYP1A2 gene.

Science.gov (United States)

Casiglia, Edoardo; Tikhonoff, Valérie; Albertini, Federica; Favaro, Jacopo; Montagnana, Martina; Danese, Elisa; Finatti, Francesco; Benati, Marco; Mazza, Alberto; Dal Maso, Lucia; Spinella, Paolo; Palatini, Paolo

2017-08-01

The possible effect of caffeine as an enhancer of cognitive performance, particularly that on abstract reasoning, has never been studied in an epidemiological setting, especially in relation to -163C>A polymorphism of CYP1A2 gene, largely controlling caffeine metabolism. Aim of this study was to ascertain whether in general population free chronic caffeine intake modifies abstract reasoning, and if this effect is influenced by the above mentioned genotype, by age, schooling, ethanol intake and smoking habits. We studied 1374 unselected men and women aged 51 ± 15 years (range 18-89) from a general population. Daily caffeine intake deriving from coffee, tea, chocolate or cola was calculated from an anamnestic questionnaire and from a 7-day dietary diary. Abstract reasoning was measured in the frame of a neuropsychological assessment as the ability to find a concept linking two words indicating objects or actions and explaining how they were connected. In age-schooling-adjusted linear regression, the higher the caffeine intake, the better the abstraction score. Abstract reasoning depended on caffeine in the -163C>A CC homozygous only (so-called slow metabolizers), where it was higher in the 3rd tertile of caffeine intake. Age and ethanol reduced while smoking and schooling enhanced this association. The interaction term between caffeine and the -163C>A polymorphism was accepted in linear regressions. Caffeine consumption resulted innocuous for the A-carriers (so-called fast metabolizers). In general population, a positive association between caffeine intake and abstract reasoning exists in the CC homozygous of the -163C>A polymorphism of CYP1A2 gene. Copyright © 2017 European Society for Clinical Nutrition and Metabolism. Published by Elsevier Ltd. All rights reserved.

Caffeine, coffee, and appetite control: a review.

Science.gov (United States)

Schubert, Matthew M; Irwin, Christopher; Seay, Rebekah F; Clarke, Holly E; Allegro, Deanne; Desbrow, Ben

2017-12-01

Coffee and caffeine consumption has global popularity. However, evidence for the potential of these dietary constituents to influence energy intake, gut physiology, and appetite perceptions remains unclear. The purpose of this review was to examine the evidence regarding coffee and caffeine's influence on energy intake and appetite control. The literature was examined for studies that assessed the effects of caffeine and coffee on energy intake, gastric emptying, appetite-related hormones, and perceptual measures of appetite. The literature review indicated that coffee administered 3-4.5 h before a meal had minimal influence on food and macronutrient intake, while caffeine ingested 0.5-4 h before a meal may suppress acute energy intake. Evidence regarding the influence of caffeine and coffee on gastric emptying, appetite hormones, and appetite perceptions was equivocal. The influence of covariates such as genetics of caffeine metabolism and bitter taste phenotype remain unknown; longer controlled studies are needed.

Adolescent intake of caffeinated energy drinks does not affect adult alcohol consumption in C57BL/6 and BALB/c mice.

Science.gov (United States)

Robins, Meridith T; DeFriel, Julia N; van Rijn, Richard M

2016-08-01

The rise in marketing and mass consumption of energy drink products by adolescents poses a largely unknown risk on adolescent development and drug reward. Yet, with increasing reports of acute health issues present in young adults who ingest large quantities of energy drinks alone or in combination with alcohol, the need to elucidate these potential risks is pressing. Energy drinks contain high levels of caffeine and sucrose; therefore, exposure to energy drinks may lead to changes in drug-related behaviors since caffeine and sucrose consumption activates similar brain pathways engaged by substances of abuse. With a recent study observing that adolescent caffeine consumption increased cocaine sensitivity, we sought to investigate how prolonged energy drink exposure in adolescence alters alcohol use and preference in adulthood. To do so, we utilized three different energy drink exposure paradigms and two strains of male mice (C57BL/6 and BALB/c) to monitor the effect of caffeine exposure via energy drinks in adolescence on adult alcohol intake. These paradigms included two models of volitional consumption of energy drinks or energy drink-like substances and one model of forced consumption of sucrose solutions with different caffeine concentrations. Following adolescent exposure to these solutions, alcohol intake was monitored in a limited-access, two-bottle choice between water and increasing concentrations of alcohol during adulthood. In none of the three models or two strains of mice did we observe that adolescent 'energy drink' consumption or exposure was correlated with changes in adult alcohol intake or preference. While our current preclinical results suggest that exposure to large amounts of caffeine does not alter future alcohol intake, differences in caffeine metabolism between mice and humans need to be considered before translating these results to humans. Copyright © 2016 Elsevier Inc. All rights reserved.

Caffeine withdrawal symptoms and self-administration following caffeine deprivation.

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Mitchell, S H; de Wit, H; Zacny, J P

1995-08-01

This study examined the effects of complete or partial caffeine deprivation on withdrawal symptomatology and self-administration of coffee in caffeine-dependent coffee drinkers. Nine habitual coffee drinkers abstained from dietary sources of caffeine for 33.5 h. Caffeine deprivation was manipulated by administering capsules containing 0%, 50%, or 100% of each subject's daily caffeine intake (complete, partial, and no deprivation conditions). Caffeine withdrawal symptomatology was measured using self-report questionnaires. Caffeine self-administration was measured using: i) the amount of coffee subjects earned on a series of concurrent random-ratio schedules that yielded coffee and money reinforcers; ii) the amount of earned coffee they consumed. Saliva samples revealed that subjects complied with the caffeine abstinence instructions. Caffeine withdrawal symptoms occurred reliably following complete caffeine deprivation, though not in the partial deprivation condition. Caffeine self-administration was not related to deprivation condition. We conclude that caffeine withdrawal symptomatology is not necessarily associated with increased caffeine consumption.

Modeling caffeine concentrations with the Stanford Caffeine Questionnaire: preliminary evidence for an interaction of chronotype with the effects of caffeine on sleep.

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Nova, Philip; Hernandez, Beatriz; Ptolemy, Adam S; Zeitzer, Jamie M

2012-04-01

To examine the validity of a novel caffeine intake questionnaire and to examine the effects of caffeine on sleep in college students. One-week, ad libitum behavior of 50 university students (28 female, 22 male; aged 20.9 ± 1.78 years) was examined with sleep logs, wrist actigraphy, and a novel daily questionnaire assessing caffeine intake at different times of day. Saliva samples were collected for caffeine assessment (questionnaire validation) and DNA extraction, and for analysis of a single nucleotide polymorphism in the adenosine receptor 2A (ADORA2A) gene. The caffeine questionnaire was able to accurately predict salivary concentrations of caffeine (R(2) = 0.41, Psleep were correlated with wake after sleep onset (WASO) most strongly in morning-type individuals (R(2) = 0.49; Psleep and genotype and chronotype. Published by Elsevier B.V.

Adherence to the Caffeine Intake Guideline during Pregnancy and Birth Outcomes: A Prospective Cohort Study.

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Peacock, Amy; Hutchinson, Delyse; Wilson, Judy; McCormack, Clare; Bruno, Raimondo; Olsson, Craig A; Allsop, Steve; Elliott, Elizabeth; Burns, Lucinda; Mattick, Richard P

2018-03-07

The aims of this study were to identify: (i) the proportion of women exceeding the caffeine intake guideline (>200 mg/day) during each trimester, accounting for point of pregnancy awareness; (ii) guideline adherence trajectories across pregnancy; (iii) maternal characteristics associated with trajectories; and (iv) association between adherence and growth restriction birth outcomes. Typical and maximal intake per consumption day for the first trimester (T1; pre- and post-pregnancy awareness), second (T2), and third trimester (T3) were recorded for a prospective cohort of pregnant Australian women with singleton births ( n = 1232). Birth outcomes were birth weight, small for gestational age, and head circumference. For each period, participants were classified as abstinent, within (≤200 mg), or in excess (>200 mg). Latent class growth analyses identified guideline adherence trajectories; regression analyses identified associations between adherence in each trimester and birth outcomes. The percentage of participants who reported caffeine use declined between T1 pre- and post-pregnancy awareness (89% to 68%), and increased in T2 and T3 (79% and 80%). Trajectories were: ' low consumption ' (22%): low probability of any use; ' within-guideline ' (70%): high probability of guideline adherence; and ' decreasing heavy use ' (8%): decreasing probability of excess use. The latter two groups were more likely to report alcohol and tobacco use, and less likely to report planning pregnancy and fertility problems. Exceeding the guideline T1 pre-pregnancy awareness was associated with lower birth weight after covariate control (b = -143.16, p = 0.011). Overall, high caffeine intake pre-pregnancy awareness occurs amongst a significant minority of women, and continued excess use post-pregnancy awareness is more common where pregnancy is unplanned. Excess caffeine consumption pre-pregnancy awareness may increase the risk for lower birth weight. Increasing awareness of the

Adherence to the Caffeine Intake Guideline during Pregnancy and Birth Outcomes: A Prospective Cohort Study

Directory of Open Access Journals (Sweden)

Amy Peacock

2018-03-01

Full Text Available The aims of this study were to identify: (i the proportion of women exceeding the caffeine intake guideline (>200 mg/day during each trimester, accounting for point of pregnancy awareness; (ii guideline adherence trajectories across pregnancy; (iii maternal characteristics associated with trajectories; and (iv association between adherence and growth restriction birth outcomes. Typical and maximal intake per consumption day for the first trimester (T1; pre- and post-pregnancy awareness, second (T2, and third trimester (T3 were recorded for a prospective cohort of pregnant Australian women with singleton births (n = 1232. Birth outcomes were birth weight, small for gestational age, and head circumference. For each period, participants were classified as abstinent, within (≤200 mg, or in excess (>200 mg. Latent class growth analyses identified guideline adherence trajectories; regression analyses identified associations between adherence in each trimester and birth outcomes. The percentage of participants who reported caffeine use declined between T1 pre- and post-pregnancy awareness (89% to 68%, and increased in T2 and T3 (79% and 80%. Trajectories were: ‘low consumption’ (22%: low probability of any use; ‘within-guideline’ (70%: high probability of guideline adherence; and ‘decreasing heavy use’ (8%: decreasing probability of excess use. The latter two groups were more likely to report alcohol and tobacco use, and less likely to report planning pregnancy and fertility problems. Exceeding the guideline T1 pre-pregnancy awareness was associated with lower birth weight after covariate control (b = −143.16, p = 0.011. Overall, high caffeine intake pre-pregnancy awareness occurs amongst a significant minority of women, and continued excess use post-pregnancy awareness is more common where pregnancy is unplanned. Excess caffeine consumption pre-pregnancy awareness may increase the risk for lower birth weight. Increasing awareness of

Caffeine intake, toxicity and dependence and lifetime risk for psychiatric and substance use disorders: an epidemiologic and co-twin control analysis.

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Kendler, Kenneth S; Myers, John; O Gardner, Charles

2006-12-01

Although caffeine is the most commonly used psychoactive substance and often produces symptoms of toxicity and dependence, little is known, especially in community samples, about the association between caffeine use, toxicity and dependence and risk for common psychiatric and substance use disorders. Assessments of lifetime maximal caffeine use and symptoms of caffeine toxicity and dependence were available on over 3600 adult twins ascertained from the population-based Virginia Twin Registry. Lifetime histories of major depression (MD), generalized anxiety disorder (GAD) and panic disorder, alcohol dependence, adult antisocial behavior and cannabis and cocaine abuse/dependence were obtained at personal interview. Logistic regression analyses in the entire sample and within monozygotic (MZ) twin pairs were conducted in SAS. In the entire sample, measures of maximal caffeine use, heavy caffeine use, and caffeine-related toxicity and dependence were significantly and positively associated with all seven psychiatric and substance use disorders. However, within MZ twin pairs, controlling for genetic and family environmental factors, these associations, while positive, were all non-significant. These results were similar when excluding twins who denied regular caffeine use. Maximal lifetime caffeine intake and caffeine-associated toxicity and dependence are moderately associated with risk for a wide range of psychiatric and substance use disorders. Analyses of these relationships within MZ twin pairs suggest that most of the observed associations are not causal. Rather, familial factors, which are probably in part genetic, predispose to both caffeine intake, toxicity and dependence and the risk for a broad array of internalizing and externalizing disorders.

Caffeine, Diabetes, Cognition, and Dementia

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Biessels, Geert Jan

2010-01-01

People with diabetes mellitus are at increased risk of cognitive dysfunction. This review explores the relation between caffeine intake, diabetes, cognition and dementia, focusing on type 2 diabetes (T2DM). Epidemiological studies on caffeine/coffee intake and T2DM risk are reviewed. Next, the

Anaphylaxis due to caffeine

OpenAIRE

Sugiyama, Kumiya; Cho, Tatsurai; Tatewaki, Masamitsu; Onishi, Shogo; Yokoyama, Tatsuya; Yoshida, Naruo; Fujimatsu, Takayoshi; Hirata, Hirokuni; Fukuda, Takeshi; Fukushima, Yasutsugu

2015-01-01

We report a rare case of anaphylaxis due to caffeine intake. A 27-year-old woman suffered her first episode of anaphylaxis and a positive skin prick test suggested that the anaphylaxis was due to an IgE-mediated hypersensitivity reaction to caffeine. She was diagnosed with caffeine allergy and has not had an allergic reaction after avoiding foods and drinks containing caffeine. Although caffeine is known to have antiallergic effects, this case shows that caffeine can be an allergen and cause ...

Caffeine and alcohol intakes and overall nutrient adequacy are associated with longitudinal cognitive performance among U.S. adults.

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Beydoun, May A; Gamaldo, Alyssa A; Beydoun, Hind A; Tanaka, Toshiko; Tucker, Katherine L; Talegawkar, Sameera A; Ferrucci, Luigi; Zonderman, Alan B

2014-06-01

Among modifiable lifestyle factors, diet may affect cognitive health. Cross-sectional and longitudinal associations may exist between dietary exposures [e.g., caffeine (mg/d), alcohol (g/d), and nutrient adequacy] and cognitive performance and change over time. This was a prospective cohort study, the Baltimore Longitudinal Study of Aging (n = 628-1305 persons depending on the cognitive outcome; ∼2 visits/person). Outcomes included 10 cognitive scores, spanning various domains of cognition. Caffeine and alcohol intakes and a nutrient adequacy score (NAS) were estimated from 7-d food diaries. Among key findings, caffeine intake was associated with better baseline global cognition among participants with a baseline age (Agebase) of ≥70 y. A higher NAS was associated with better baseline global cognition performance (overall, women, Agebase memory (immediate and delayed recall, Agebase ≥70 y), and slower rate of decline or faster improvement in the attention domain (women). For an Agebase of memory. In sum, patterns of diet and cognition associations indicate stratum-specific associations by sex and baseline age. The general observed trend was that of putative beneficial effects of caffeine intake and nutrient adequacy on domains of global cognition, verbal memory, and attention, and mixed effects of alcohol on domains of letter fluency, attention, and working memory. Further longitudinal studies conducted on larger samples of adults are needed to determine whether dietary factors individually or in combination are modifiers of cognitive trajectories among adults. © 2014 American Society for Nutrition.

Pharmacokinetics of Caffeine in the Lens Capsule/Epithelium After Peroral Intake: A Pilot Randomized Controlled Study.

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Kronschläger, Martin; Stimpfl, Thomas; Ruiß, Manuel; Hirnschall, Nino; Leisser, Christoph; Findl, Oliver

2018-04-01

To determine the pharmacokinetics of perorally administered caffeine, a widely consumed and potent dietary antioxidant, in the anterior lens capsule and lens epithelial cells, a crucial cell monolayer for cataract development. Bilateral cataract patients were scheduled for cataract surgery with a caffeine abstinence of 1 week before surgery of each eye. At the day of surgery of the second eye patients were administered no drink (0-mg group) or coffee with 60-, 120-, or 180-mg caffeine. After capsulorhexis the lens capsule including lens epithelial cells was transferred to a test tube for analysis of caffeine concentration by gas chromatography-mass spectrometry (GC-MS/MS). Coffee consumption significantly (P < 0.05) increased caffeine levels of the lens capsule/epithelium in the 60-, 120-, and 180-mg group. Caffeine concentrations (caffeine ng/lens capsule/epithelium) measured as difference between 1st and 2nd eye were -0.52 ± 1.16 (0-mg group, n = 7), 1.88 ± 2.02 (60-mg group, n = 8), 2.09 ± 0.67 (120-mg group, n = 9), and 3.68 ± 1.86 (180-mg group, n = 9). The increase constant of caffeine in a linear regression model was estimated as a 95% CI 0.02 ± 0.0046 (degrees of freedom; 25; r = 0.85). Peroral intake of coffee significantly increased caffeine concentrations in the lens capsule and lens epithelial cells in a dose-dependent manner. This information is important for further investigations on preventing cataract.

Association of the Anxiogenic and Alerting Effects of Caffeine with ADORA2A and ADORA1 Polymorphisms and Habitual Level of Caffeine Consumption

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Rogers, Peter J; Hohoff, Christa; Heatherley, Susan V; Mullings, Emma L; Maxfield, Peter J; Evershed, Richard P; Deckert, Jürgen; Nutt, David J

2010-01-01

Caffeine, a widely consumed adenosine A1 and A2A receptor antagonist, is valued as a psychostimulant, but it is also anxiogenic. An association between a variant within the ADORA2A gene (rs5751876) and caffeine-induced anxiety has been reported for individuals who habitually consume little caffeine. This study investigated whether this single nucleotide polymorphism (SNP) might also affect habitual caffeine intake, and whether habitual intake might moderate the anxiogenic effect of caffeine. Participants were 162 non-/low (NL) and 217 medium/high (MH) caffeine consumers. In a randomized, double-blind, parallel groups design they rated anxiety, alertness, and headache before and after 100 mg caffeine and again after another 150 mg caffeine given 90 min later, or after placebo on both occasions. Caffeine intake was prohibited for 16 h before the first dose of caffeine/placebo. Results showed greater susceptibility to caffeine-induced anxiety, but not lower habitual caffeine intake (indeed coffee intake was higher), in the rs5751876 TT genotype group, and a reduced anxiety response in MH vs NL participants irrespective of genotype. Apart from the almost completely linked ADORA2A SNP rs3761422, no other of eight ADORA2A and seven ADORA1 SNPs studied were found to be clearly associated with effects of caffeine on anxiety, alertness, or headache. Placebo administration in MH participants decreased alertness and increased headache. Caffeine did not increase alertness in NL participants. With frequent consumption, substantial tolerance develops to the anxiogenic effect of caffeine, even in genetically susceptible individuals, but no net benefit for alertness is gained, as caffeine abstinence reduces alertness and consumption merely returns it to baseline. PMID:20520601

Effects of caffeine intake on muscle strength and power: a systematic review and meta-analysis.

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Grgic, Jozo; Trexler, Eric T; Lazinica, Bruno; Pedisic, Zeljko

2018-01-01

Caffeine is commonly used as an ergogenic aid. Literature about the effects of caffeine ingestion on muscle strength and power is equivocal. The aim of this systematic review and meta-analysis was to summarize results from individual studies on the effects of caffeine intake on muscle strength and power. A search through eight databases was performed to find studies on the effects of caffeine on: (i) maximal muscle strength measured using 1 repetition maximum tests; and (ii) muscle power assessed by tests of vertical jump. Meta-analyses of standardized mean differences (SMD) between placebo and caffeine trials from individual studies were conducted using the random effects model. Ten studies on the strength outcome and ten studies on the power outcome met the inclusion criteria for the meta-analyses. Caffeine ingestion improved both strength (SMD = 0.20; 95% confidence interval [CI]: 0.03, 0.36; p  = 0.023) and power (SMD = 0.17; 95% CI: 0.00, 0.34; p  = 0.047). A subgroup analysis indicated that caffeine significantly improves upper (SMD = 0.21; 95% CI: 0.02, 0.39; p  = 0.026) but not lower body strength (SMD = 0.15; 95% CI: -0.05, 0.34; p  = 0.147). The meta-analyses showed significant ergogenic effects of caffeine ingestion on maximal muscle strength of upper body and muscle power. Future studies should more rigorously control the effectiveness of blinding. Due to the paucity of evidence, additional findings are needed in the female population and using different forms of caffeine, such as gum and gel.

Caffeine, creatine, GRIN2A and Parkinson's disease progression.

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Simon, David K; Wu, Cai; Tilley, Barbara C; Lohmann, Katja; Klein, Christine; Payami, Haydeh; Wills, Anne-Marie; Aminoff, Michael J; Bainbridge, Jacquelyn; Dewey, Richard; Hauser, Robert A; Schaake, Susen; Schneider, Jay S; Sharma, Saloni; Singer, Carlos; Tanner, Caroline M; Truong, Daniel; Wei, Peng; Wong, Pei Shieen; Yang, Tianzhong

2017-04-15

Caffeine is neuroprotective in animal models of Parkinson's disease (PD) and caffeine intake is inversely associated with the risk of PD. This association may be influenced by the genotype of GRIN2A, which encodes an NMDA-glutamate-receptor subunit. In two placebo-controlled studies, we detected no association of caffeine intake with the rate of clinical progression of PD, except among subjects taking creatine, for whom higher caffeine intake was associated with more rapid progression. We now have analyzed data from 420 subjects for whom DNA samples and caffeine intake data were available from a placebo-controlled study of creatine in PD. The GRIN2A genotype was not associated with the rate of clinical progression of PD in the placebo group. However, there was a 4-way interaction between GRIN2A genotype, caffeine, creatine and the time since baseline. Among subjects in the creatine group with high levels of caffeine intake, but not among those with low caffeine intake, the GRIN2A T allele was associated with more rapid progression (p=0.03). These data indicate that the deleterious interaction between caffeine and creatine with respect to rate of progression of PD is influenced by GRIN2A genotype. This example of a genetic factor interacting with environmental factors illustrates the complexity of gene-environment interactions in the progression of PD. Copyright © 2017 Elsevier B.V. All rights reserved.

Nearly half of the adolescents in an Italian school-based study exceeded the recommended upper limits for daily caffeine consumption.

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Santangelo, Barbara; Lapolla, Rosa; Rutigliano, Irene; Pettoello Mantovani, Massimo; Campanozzi, Angelo

2018-06-01

No data are available on caffeine consumption among Italian adolescents. We investigated caffeine intake from coffee, soft drinks and energy drinks in a sample of Italian adolescents and determined if they exceeded the recommended limits. The study comprised 1213 adolescents with a mean age of 15.1 years (range 12-19) from four schools in Foggia, southern Italy. Caffeine intake was assessed using an anonymous self-reported questionnaire during the 2013/2014 school year. We calculated the percentage of daily caffeine consumers, their mean intake of caffeine from beverages and the contribution of each beverage category to the total caffeine intake. Approximately 76% of the sample consumed caffeine every day, amounting to 125.5 ± 69.2 mg/day and 2.1 ± 1.2 mg/kg/day. When we applied the reference values from the Academy of Pediatrics, we found that 46% of the adolescents exceeded the recommended upper limits. Coffee was the most frequently consumed caffeinated drink and the main contributor to daily caffeine intake. More than three quarters (76%) of the Italian adolescents in our study drank coffee on a daily basis and nearly half (46%) exceeded the recommended upper limits. Strategies are needed to reduce caffeine consumption by adolescents. ©2018 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

Caffeine, mental health, and psychiatric disorders.

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Lara, Diogo R

2010-01-01

Caffeine intake is so common that its pharmacological effects on the mind are undervalued. Since it is so readily available, individuals can adjust their own dose, time of administration and dose intervals of caffeine, according to the perceived benefits and side effects of each dose. This review focuses on human studies of caffeine in subjects with and without psychiatric disorders. Besides the possibility of mild drug dependence, caffeine may bring benefits that contribute to its widespread use. These benefits seem to be related to adaptation of mental energy to the context by increasing alertness, attention, and cognitive function (more evident in longer or more difficult tasks or situations of low arousal) and by elevating mood. Accordingly, moderate caffeine intake (caffeine can induce psychotic and manic symptoms, and more commonly, anxiety. Patients with panic disorder and performance social anxiety disorder seem to be particularly sensitive to the anxiogenic effects of caffeine, whereas preliminary data suggests that it may be effective for some patients with obsessive compulsive disorder (OCD). The threshold for the anxiogenic effect of caffeine is influenced by a polymorphism of the A2A receptor. In summary, caffeine can be regarded as a pharmacological tool to increase energy and effortful behavior in daily activities. More populational (cross-sectional and prospective) and experimental studies are necessary to establish the role of caffeine intake in psychiatric disorders, especially its putative efficacy on depressive mood and cognitive/attentional disorders.

Caffeine and Alcohol Intakes and Overall Nutrient Adequacy Are Associated with Longitudinal Cognitive Performance among U.S. Adults123

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Beydoun, May A.; Gamaldo, Alyssa A.; Beydoun, Hind A.; Tanaka, Toshiko; Tucker, Katherine L.; Talegawkar, Sameera A.; Ferrucci, Luigi; Zonderman, Alan B.

2014-01-01

Among modifiable lifestyle factors, diet may affect cognitive health. Cross-sectional and longitudinal associations may exist between dietary exposures [e.g., caffeine (mg/d), alcohol (g/d), and nutrient adequacy] and cognitive performance and change over time. This was a prospective cohort study, the Baltimore Longitudinal Study of Aging (n = 628–1305 persons depending on the cognitive outcome; ∼2 visits/person). Outcomes included 10 cognitive scores, spanning various domains of cognition. Caffeine and alcohol intakes and a nutrient adequacy score (NAS) were estimated from 7-d food diaries. Among key findings, caffeine intake was associated with better baseline global cognition among participants with a baseline age (Agebase) of ≥70 y. A higher NAS was associated with better baseline global cognition performance (overall, women, Agebase memory (immediate and delayed recall, Agebase ≥70 y), and slower rate of decline or faster improvement in the attention domain (women). For an Agebase of memory. In sum, patterns of diet and cognition associations indicate stratum-specific associations by sex and baseline age. The general observed trend was that of putative beneficial effects of caffeine intake and nutrient adequacy on domains of global cognition, verbal memory, and attention, and mixed effects of alcohol on domains of letter fluency, attention, and working memory. Further longitudinal studies conducted on larger samples of adults are needed to determine whether dietary factors individually or in combination are modifiers of cognitive trajectories among adults. PMID:24744319

Blood pressure response to caffeine shows incomplete tolerance after short-term regular consumption.

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Lovallo, William R; Wilson, Michael F; Vincent, Andrea S; Sung, Bong Hee; McKey, Barbara S; Whitsett, Thomas L

2004-04-01

Caffeine acutely raises blood pressure (BP). The clinical significance of this effect depends on whether BP responses persist in persons who consume caffeine on a daily basis. Accordingly, the ability of caffeine to raise BP after 5 days of regular daily intake was tested in a randomized controlled trial. Individual differences in tolerance formation were then examined. Men (n=49) and women (n=48) completed a double-blind, crossover trial conducted over 4 weeks. During each week, subjects abstained for 5 days from dietary caffeine and instead used capsules totaling 0 mg, 300 mg, and 600 mg of caffeine per day in 3 divided doses. On day 6, in the laboratory, they used capsules with either 0 mg or 250 mg of caffeine at 9:00 am and 1:00 pm. Systolic/diastolic BP increases as a result of 250 mg of caffeine remained significant (P7.90, P <0.001). The sexes did not differ in degree of tolerance formation. Daily caffeine consumption failed to eliminate the BP response to repeated challenge doses of caffeine in half of the healthy adults who were tested. Caffeine may therefore cause persistent BP effects in persons who are regular consumers, even when daily intake is at moderately high levels.

Caffeine: sleep and daytime sleepiness.

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Roehrs, Timothy; Roth, Thomas

2008-04-01

Caffeine is one of the most widely consumed psychoactive substances and it has profound effects on sleep and wake function. Laboratory studies have documented its sleep-disruptive effects. It clearly enhances alertness and performance in studies with explicit sleep deprivation, restriction, or circadian sleep schedule reversals. But, under conditions of habitual sleep the evidence indicates that caffeine, rather then enhancing performance, is merely restoring performance degraded by sleepiness. The sleepiness and degraded function may be due to basal sleep insufficiency, circadian sleep schedule reversals, rebound sleepiness, and/or a withdrawal syndrome after the acute, over-night, caffeine discontinuation typical of most studies. Studies have shown that caffeine dependence develops at relatively low daily doses and after short periods of regular daily use. Large sample and population-based studies indicate that regular daily dietary caffeine intake is associated with disturbed sleep and associated daytime sleepiness. Further, children and adolescents, while reporting lower daily, weight-corrected caffeine intake, similarly experience sleep disturbance and daytime sleepiness associated with their caffeine use. The risks to sleep and alertness of regular caffeine use are greatly underestimated by both the general population and physicians.

CAFFEINE INTAKE ENHANCES ENDURANCE PERFORMANCE IN SUB-ELITE BUT NOT IN ELITE ATHLETES

Directory of Open Access Journals (Sweden)

Ondřej Smolka

2015-01-01

Full Text Available The aim of our contribution is to evaluate the influence of caffeine (CAF ingestion on maximal power output (MPO during endurance performance. Two groups of men – 10 sub-elite cyclists and 8 elite cyclists completed a randomized, crossover, double-blind study. Over the course of three days participants completed three identical experimental tests (60min cycling time trial on 70 % VO2max followed by test to exhaustion. Three experimental meals - a combination of 500ml water, a gel supplement and a specific dose of CAF: a placebo (PLA, no caffeine, CAF2 (2 mg / kg body weight (BW and CAF7 (7 mg / kg BW were administered 45min prior to the start of the experimental tests. Subjective RPE values were determined using the Borg 20-category scale. The results show significant differences between MPOPLA and MPOCAF7 and between MPOCAF2 and MPOCAF7 with p = 0.018 and p = 0.019, respectively, in the sub-elite cyclists group only. The mean MPO during experimental test in sub-elite cyclists, but not in elite cyclists, was significantly enhanced following caffeine ingestion (p = 0.05. These findings indicate that caffeine intake at recommended levels is not associated with improved performance in a professional level cyclist. The results of the comparison of the experimental situations using the Borg scale are not persuasive. We found a significant difference (0.008356 between the PLA and CAF2 experimental measurements (p < 0.05. The level of substantive significance was assessed using Cohen’s coefficient effect and only a small “size of effect” (0.19 was found. It is therefore not possible to determine whether the Borg scale might be used to define the effects of caffeine ingestion on endurance performance, due to the multifactorial effects of caffeine.

Caffeine content of decaffeinated coffee.

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McCusker, Rachel R; Fuehrlein, Brian; Goldberger, Bruce A; Gold, Mark S; Cone, Edward J

2006-10-01

Caffeine is the most widely consumed drug in the world with coffee representing a major source of intake. Despite widespread availability, various medical conditions necessitate caffeine-restricted diets. Patients on certain prescription medications are advised to discontinue caffeine intake. Such admonition has implications for certain psychiatric patients because of pharmacokinetic interactions between caffeine and certain anti-anxiety drugs. In an effort to abstain from caffeine, patients may substitute decaffeinated for caffeinated coffee. However, decaffeinated beverages are known to contain caffeine in varying amounts. The present study determined the caffeine content in a variety of decaffeinated coffee drinks. In phase 1 of the study, 10 decaffeinated samples were collected from different coffee establishments. In phase 2 of the study, Starbucks espresso decaffeinated (N=6) and Starbucks brewed decaffeinated coffee (N=6) samples were collected from the same outlet to evaluate variability of caffeine content of the same drink. The 10 decaffeinated coffee samples from different outlets contained caffeine in the range of 0-13.9 mg/16-oz serving. The caffeine content for the Starbucks espresso and the Starbucks brewed samples collected from the same outlet were 3.0-15.8 mg/shot and 12.0-13.4 mg/16-oz serving, respectively. Patients vulnerable to caffeine effects should be advised that caffeine may be present in coffees purported to be decaffeinated. Further research is warranted on the potential deleterious effects of consumption of "decaffeinated" coffee that contains caffeine on caffeine-restricted patients. Additionally, further exploration is merited for the possible physical dependence potential of low doses of caffeine such as those concentrations found in decaffeinated coffee.

Caffeine's influence on gambling behavior and other types of impulsivity.

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Grant, Jon E; Chamberlain, Samuel R

2018-01-01

Young adulthood is a developmental period frequently associated with occurrence of impulsive behaviors including gambling. It is estimated that 73% of children and 87% of adults in the United States regularly use caffeine. Questions remain, however, concerning the role of caffeine in the development and maintenance of impulsive behaviors such as gambling. Sixty-one young adults with at least some degree of disordered gambling were recruited from two Mid-Western university communities in the United States using media advertisements. Caffeine intake over the preceding month was quantified using the Caffeine Use Questionnaire. Clinician rating scales, questionnaires, and cognitive tests germane to impulsivity were completed. Relationships between caffeine intake and demographic, gambling symptom, and neurocognitive measures were evaluated using the statistical technique of partial least squares (PLS). Average weekly caffeine intake in the gamblers was 1218.5mg (a figure higher than previously reported in the general population). PLS yielded an optimal model with one latent factor, which explained 14.8% of variation in demographic/clinical/cognitive measures and 32.3% of variation in caffeine intake. In this model, higher caffeine intake was significantly associated with earlier age at first gambling, higher personality-related impulsiveness, more nicotine consumption, older age, and more impulsive decision-making. These data suggest a particularly strong relationship between caffeine intake, earlier age of first gambling, and certain types of impulsivity in gamblers. Providing education about healthy caffeine use may be especially valuable in gamblers. Future work should explore whether the relationship between caffeine use and gambling is due to a common predisposing factor (impulsive tendencies) or, rather, constitutes a form of self-medication in gamblers (or a means of sustaining gambling habits for longer). Copyright © 2017 Elsevier Ltd. All rights reserved.

Patterns of caffeine consumption in psychiatric patients. An Italian study.

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Ciapparelli, A; Paggini, R; Carmassi, C; Taponecco, C; Consoli, G; Ciampa, G; Ramacciotti, C E; Marazziti, D; Dell'Osso, L

2010-05-01

The aim of the present study was to explore and compare the caffeine intake, intoxication, withdrawal and dependence prevalence in Italian psychiatric patients and healthy subjects. Three hundred and sixty-nine out- and inpatients, suffering from different psychiatric disorders, and 104 healthy subjects were included in the study. They were assessed by the SCID and by a structured interview for caffeine intoxication and withdrawal and for substance dependence applied to caffeine use. Patients and healthy subjects did not differ in terms of current caffeine intake (mg/day, mean+/-SD: 281+/-325 vs. 288+/-148, respectively), while the maximum lifetime intake of caffeine was significantly higher in the first group (mg/day, mean SD: 630+/-549 vs. 504+/-344, respectively; F=4.897, p=.03) where it was significantly related to the CGI severity item scores (rho=.107; p=.04). In both patients and healthy subjects, a lower age was related to a higher current caffeine intake, while both current and maximum lifetime caffeine intake in the healthy subjects were significantly higher in men than in women. The patients suffering from eating disorders reported higher current caffeine intake than those with anxiety or mood disorders. The prevalence of dependence and intoxication was significantly higher in the patients than in the healthy subjects, without inter-group differences. Healthy subjects showed a trend towards a higher prevalence of withdrawal. Our study highlights the need that a more accurate attention should be paid to the caffeine use which seems to be strongly, although generically, related to different psychiatric disorders. (c) 2009 Elsevier Masson SAS. All rights reserved.

Caffeine dependence in teenagers.

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Bernstein, Gail A; Carroll, Marilyn E; Thuras, Paul D; Cosgrove, Kelly P; Roth, Megan E

2002-03-01

This study identifies and characterizes symptoms of caffeine dependence in adolescents. Thirty-six adolescents who consumed caffeine daily and had some features of caffeine dependence on telephone screen were scheduled for outpatient evaluation. Evaluation included the Diagnostic Interview Schedule for Children-IV-Youth Version (DISC-IV) and modified DISC-IV questions that assessed caffeine dependence based on DSM-IV substance dependence criteria. Of 36 subjects, 41.7% (n=15) reported tolerance to caffeine, 77.8% (n=28) described withdrawal symptoms after cessation or reduction of caffeine intake, 38.9% (n=14) reported desire or unsuccessful attempts to control use, and 16.7% (n=6) endorsed use despite knowledge of physical or psychological problems associated with caffeine. There was no significant difference in the amount of caffeine consumed daily by caffeine dependent versus non-dependent teenagers. These findings are important due to the vast number of adolescents who drink caffeinated beverages.

Effects of smoking cues on caffeine urges in heavy smokers and caffeine consumers with and without schizophrenia.

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Adolfo, Amy B; AhnAllen, Christopher G; Tidey, Jennifer W

2009-02-01

Cigarette smoking and caffeine use are established and problematic drug-use behaviors in people with schizophrenia. Associative links between drugs of abuse may occur but the relationship between caffeine use and cigarette smoking has received little attention in schizophrenia. In this cross-cue reactivity laboratory study, we examined the effects of neutral and smoking cues on craving for caffeinated beverages in participants with schizophrenia or schizoaffective disorder (SS; n=15) and non-psychiatric controls (CS; n=18) all of whom were heavy smokers and daily caffeine users. Participants were tested under non-abstinent and 5-hour abstinent conditions. SS tended to report greater daily levels of caffeine use than CS. Although this difference was not significant, that may be due to the small sample sizes as the size of this effect was large. Daily caffeine intake was significantly correlated with daily smoking rate in SS but not CS. A significant interaction between group and cue type after controlling for caffeine intake indicated that exposure to smoking cues increased urge for caffeinated beverages in SS but not CS. These results indicate support for associative connections between cigarette smoking cues and craving for caffeine in smokers with schizophrenia.

Differential responsiveness to caffeine and perceived effects of caffeine in moderate and high regular caffeine consumers.

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Attwood, A S; Higgs, S; Terry, P

2007-03-01

Individual differences in responsiveness to caffeine occur even within a caffeine-consuming population, but the factors that mediate differential responsiveness remain unclear. To compare caffeine's effects on performance and mood in a group of high vs moderate consumers of caffeine and to examine the potential role of subjective awareness of the effects of caffeine in mediating any differential responsiveness. Two groups of regular caffeine consumers (200 mg/day) attended two sessions at which mood and cognitive functions were measured before and 30 min after consumption of 400-mg caffeine or placebo in a capsule. Cognitive tests included visual information processing, match-to-sample visual search (MTS) and simple and choice reaction times. Post-session questionnaires asked participants to describe any perceived effect of capsule consumption. High consumers, but not moderate consumers, demonstrated significantly faster simple and choice reaction times after caffeine relative to placebo. These effects were not attributable to obvious group differences in withdrawal or tolerance because there were no group differences in baseline mood or in reports of negative affect after caffeine. Instead, the high consumers were more likely to report experiencing positive effects of caffeine, whereas the moderate consumers were more likely to report no effect. The sensitivity of caffeine consumers to the mood- and performance-enhancing effects of caffeine is related to their levels of habitual intake. High caffeine consumers are more likely than moderate consumers to perceive broadly positive effects of caffeine, and this may contribute to their levels of use.

Caffeine consumption and cognitive function at age 70: the Lothian Birth Cohort 1936 study.

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Corley, Janie; Jia, Xueli; Kyle, Janet A M; Gow, Alan J; Brett, Caroline E; Starr, John M; McNeill, Geraldine; Deary, Ian J

2010-02-01

To investigate the association between caffeine consumption and cognitive outcomes in later life. Participants were 923 healthy adults from the Lothian Birth Cohort 1936 Study, on whom there were intelligence quotient (IQ) data from age 11 years. Cognitive function at age 70 years was assessed, using tests measuring general cognitive ability, speed of information processing, and memory. Current caffeine consumption (using multiple measures of tea, coffee, and total dietary caffeine) was obtained by self-report questionnaire, and demographic and health information was collected in a standardized interview. In age- and sex-adjusted models, there were significant positive associations between total caffeine intake and general cognitive ability and memory. After adjustment for age 11 IQ and social class, both individually and together, most of these associations became nonsignificant. A robust positive association, however, was found between drinking ground coffee (e.g., filter and espresso) and performance on the National Adult Reading Test (NART, p = .007), and the Wechsler Test of Adult Reading (WTAR, p = .02). No gender effects were observed, contrary to previous studies. Generally, higher cognitive scores were associated with coffee consumption, and lower cognitive scores with tea consumption, but these effects were not significant in the fully adjusted model. The present study is rare in having childhood IQ in a large sample of older people. The results suggest that the significant caffeine intake-cognitive ability associations are bidirectional-because childhood IQ and estimated prior IQ are associated with the type of caffeine intake in old age-and partly confounded by social class.

Disagreement between splenic switch-off and myocardial T1-mapping after caffeine intake.

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Kuijpers, Dirkjan; van Dijk, Randy; van Assen, Marly; Kaandorp, Theodorus A M; van Dijkman, Paul R M; Vliegenthart, Rozemarijn; van der Harst, Pim; Oudkerk, Matthijs

2018-04-01

Caffeine is an adenosine receptor antagonist and a possible cause of inadequate stress perfusion. Splenic switch-off (SSO) and splenic rest-stress T1-mapping have been proposed as indicators of stress adequacy during perfusion cardiac magnetic resonance (CMR). We compared myocardial rest-stress T1-mapping with SSO and splenic rest-stress T1-mapping in patients with and without recent coffee intake. We analyzed 344 consecutive patients suspected of myocardial ischemia with adenosine perfusion CMR. All 146 normal CMR studies with a normal T1-rest of the myocardium, used as standard of reference, were included and divided in two groups. 22 patients accidentally ingested coffee < 4 h before CMR, compared to control group of 124 patients without self-reported coffee intake. Two independent readers graded SSO visually. T1-reactivity (ΔT1) was defined as percentual difference in T1-rest and T1-stress. Follow-up data were extracted from electronic patients records. In patients with recent coffee intake SSO was identified in 96%, which showed no significant difference with SSO in controls (94%, p = 0.835), however event rates were significantly different (13.6 and 0.8%, respectively (p < 0.001), median FU 17 months). Myocardial ΔT1 in the coffee group (- 5.2%) was significantly lower compared to control (+ 4.0%, p < 0.001), in contrast to the splenic ΔT1 (- 3.7 and - 4.0%, p = 0.789). The splenic T1-mapping results failed to predict false negative results. SSO and splenic rest-stress T1-mapping are not reliable indicators of stress adequacy in patients with recent coffee intake. Therefore, the dark spleen sign does not indicate adequate myocardial stress in patients with recent caffeine intake. Myocardial rest-stress T1-mapping is an excellent indicator of stress adequacy during adenosine perfusion CMR.

The Cumulative Neurobehavioral and Physiological Effects of Chronic Caffeine Intake: Individual Differences and Implications for the Use of Caffeinated Energy Products

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Spaeth, Andrea M; Goel, Namni; Dinges, David F

2014-01-01

The use of caffeine-containing energy products (CCEP) has increased worldwide in recent years and research shows that CCEP can improve cognitive and physical performance. All of the top-selling energy drinks contain caffeine, which is likely to be the primary psychoactive ingredient in CCEP. Presumably, individuals consume CCEP to counteract feelings of ‘low-energy’ in situations causing tiredness, fatigue, and/or reduced alertness. This review discusses the scientific evidence for sleep loss, circadian phase, sleep inertia and the time-on-task effect as causes of ‘low energy’ and summarizes research assessing the efficacy of caffeine to counteract decreased alertness and increased fatigue in such situations. The results of a placebo-controlled experiment on healthy adults undergoing three nights of total sleep deprivation (with or without 2 hour naps every 12 hours) are presented to illustrate the physiological and neurobehavioral effects of sustained low-dose caffeine. Individual differences, including genetic factors, in the response to caffeine and to sleep loss are discussed. We conclude with future directions for research on this important and evolving topic. PMID:25293542

Effects of low doses of caffeine on cognitive performance, mood and thirst in low and higher caffeine consumers.

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Smit, H J; Rogers, P J

2000-10-01

Caffeine is present in many widely consumed drinks and some foods. In the fairly extensive literature on the psychostimulant effects of caffeine, there are few dose-response studies and even fewer studies of the effects of doses of caffeine lower than 50 mg (the range of the amounts of caffeine contained in, for example, a typical serving of tea or cola). This study measured the effects of 0, 12.5, 25, 50 and 100 mg caffeine on cognitive performance, mood and thirst in adults with low and moderate to high habitual caffeine intakes. This was a double-blind, within-subjects study. Following overnight caffeine abstinence, participants (n=23) completed a test battery once before and three times after placebo or caffeine administration. The test battery consisted of two performance tests, a long duration simple reaction time task and a rapid visual information processing task, and a mood questionnaire (including also an item on thirst). Effects on performance and mood confirmed a psychostimulant action of caffeine. All doses of caffeine significantly affected cognitive performance, and the dose-response relationships for these effects were rather flat. The effects on performance were more marked in individuals with a higher level of habitual caffeine intake, whereas caffeine increased thirst only in low caffeine consumers. After overnight caffeine abstinence, caffeine can significantly affect cognitive performance, mood and thirst at doses within and even lower than the range of amounts of caffeine contained in a single serving of popular caffeine-containing drinks. Regular caffeine consumers appear to show substantial tolerance to the thirst-increasing but not to the performance and mood effects of caffeine.

Excessive oral intake caffeine altered cerebral cortex ...

African Journals Online (AJOL)

Caffeine is commonly consumed in an effort to enhance speed in performance and wakefulness. However, little is known about the deleterious effects it can produce on the brain, this study aimed at determining the extents of effects and damage that can be caused by excessive consumption of caffeine on the cerebral cortex ...

Cognitive and psychomotor performance, mood, and pressor effects of caffeine after 4, 6 and 8 h caffeine abstinence.

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Heatherley, Susan V; Hayward, Robert C; Seers, Helen E; Rogers, Peter J

2005-04-01

Many studies have found that caffeine consumed after overnight caffeine abstinence improves cognitive performance and mood. Much less is known, however, about the effects of caffeine after shorter periods of caffeine abstinence. The aim of this study was to measure the effects on psychomotor and cognitive performance, mood, hand steadiness, blood pressure and heart rate of caffeine administration after periods of 4, 6, and 8 h of caffeine abstinence. Participants (n = 49, 27 female) were moderate to moderate-high caffeine consumers (mean daily intake 370 mg/day). Following overnight caffeine abstinence, a 'pre-dose' of caffeine (1.2 mg/kg) was administered at 9 A.M, 11 A.M or 1 P.M. The participants started a baseline battery of measurements at 4 P.M.: before receiving caffeine (1.2 mg/kg) or placebo at 5 P.M.: They then performed the battery of tests again, starting at 5:30 P.M. This was a double-blind, placebo-controlled, randomised study. Performance and mood measurements confirmed a psychostimulant action of caffeine (versus placebo), but only after 8 h of caffeine abstinence. Caffeine also increased blood pressure after 8-h abstinence, whereas hand steadiness was decreased and perception of task demand was increased by caffeine after 4 h, but not after 6- and 8-h abstinence. A second cup-of-coffee equivalent dose of caffeine only reliably affected cognitive performance and mood after an 8-h interval between doses, but not after shorter intervals (when caffeine had some adverse effects). These results show that, apart from caffeine consumption soon after waking, the daily pattern of caffeine intake of many typical caffeine consumers is not well explained by the short-term psychostimulant effects of caffeine.

Effect of caffeine intake on critical power model parameters determined on a cycle ergometer DOI:10.5007/1980-0037.2010v12n1p49

Directory of Open Access Journals (Sweden)

Marcus Vinicius Machado

2010-12-01

Full Text Available The aim of this study was to evaluate the effect of caffeine intake on critical power model parameters determined on a cycle ergometer. Eight male subjects participated in this study. A double-blind protocol consisting of the intake of pure caffeine (6 mg/kg or placebo (maltodextrin 60 min before testing was used. Subjects were submitted to four constant-load tests on a cycle ergometer. These tests were conducted randomly in the caffeine and placebo groups [checar] at intensities of 80, 90, 100 and 110% maximum power at a rate of 70 rpm until exhaustion to determine the critical power. As a criterion for stopping the test was adopted any rate fall without recovery by more than five seconds. The critical power and anaerobic work capacity were obtained by nonlinear regression and fitting of the curve to a hyperbolic power-time model. The Shapiro-Wilk test and paired Student t-test were used for statistical analysis. No significant differences in critical power were observed between the caffeine and placebo groups (192.9 ± 31.3 vs 197.7 ± 29.4 W, respectively. The anaerobic work capacity was significantly higher in the caffeine group (20.1 ± 5.2 vs 16.3 ± 4.2 W, p< 0.01. A high association (r2 was observed between the caffeine and placebo conditions (0.98 ± 0.02 and 0.99 ± 0.0, respectively. We conclude that caffeine intake did not improve critical power performance but increased anaerobic work capacity by influencing performance at loads of higher intensity and shorter duration.

Caffeine use disorder: An item-response theory analysis of proposed DSM-5 criteria.

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Ágoston, Csilla; Urbán, Róbert; Richman, Mara J; Demetrovics, Zsolt

2018-06-01

Caffeine is a common psychoactive substance with a documented addictive potential. Caffeine withdrawal has been included in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), but caffeine use disorder (CUD) is considered to be a condition for further study. The aim of the current study is (1) to test the psychometric properties of the Caffeine Use Disorder Questionnaire (CUDQ) by using a confirmatory factor analysis and an item response theory (IRT) approach, (2) to compare IRT models with varying numbers of parameters and models with or without caffeine consumption criteria, and (3) to examine if the total daily caffeine consumption and the use of different caffeinated products can predict the magnitude of CUD symptomatology. A cross-sectional study was conducted on an adult sample (N = 2259). Participants answered several questions regarding their caffeine consumption habits and completed the CUDQ, which incorporates the nine proposed criteria of the DSM-5 as well as one additional item regarding the suffering caused by the symptoms. Factor analyses demonstrated the unidimensionality of the CUDQ. The suffering criterion had the highest discriminative value at a higher degree of latent trait. The criterion of failure to fulfill obligations and social/interpersonal problems discriminate only at the higher value of CUD latent factor, while endorsement the consumption of more caffeine or longer than intended and craving criteria were discriminative at a lower level of CUD. Total daily caffeine intake was related to a higher level of CUD. Daily coffee, energy drink, and cola intake as dummy variables were associated with the presence of more CUD symptoms, while daily tea consumption as a dummy variable was related to less CUD symptoms. Regular smoking was associated with more CUD symptoms, which was explained by a larger caffeine consumption. The IRT approach helped to determine which CUD symptoms indicate more severity and have a greater

Intake of Japanese and Chinese teas reduces risk of Parkinson's disease.

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Tanaka, Keiko; Miyake, Yoshihiro; Fukushima, Wakaba; Sasaki, Satoshi; Kiyohara, Chikako; Tsuboi, Yoshio; Yamada, Tatsuo; Oeda, Tomoko; Miki, Takami; Kawamura, Nobutoshi; Sakae, Nobutaka; Fukuyama, Hidenao; Hirota, Yoshio; Nagai, Masaki

2011-07-01

Studies that have addressed the association between the intake of coffee or caffeine and Parkinson's disease (PD) were conducted mainly in Western countries. Little is known about this relationship in an Asian population. Therefore, we performed an assessment of the association of the intake of coffee, other caffeine-containing beverages, and caffeine with the risk of PD in Japan. The study involved 249 PD cases and 368 control subjects. Information on dietary factors was obtained through a self-administered diet history questionnaire. Adjustment was made for sex, age, region of residence, educational level, pack-years of smoking, body mass index, the dietary glycemic index, and intake of cholesterol, vitamin E, β-carotene, vitamin B(6,) alcohol, and iron. Intake of coffee, black tea, and Japanese and Chinese teas was significantly inversely associated with the risk of PD: the adjusted odds ratios in comparison of the highest with the lowest quartile were 0.52, 0.58, and 0.59, respectively (95% confidence intervals = 0.30-0.90, 0.35-0.97, and 0.35-0.995, respectively). A clear inverse dose-response relationship between total caffeine intake and PD risk was observed. We confirmed that the intake of coffee and caffeine reduced the risk of PD. Furthermore, this is the first study to show a significant inverse relationship between the intake of Japanese and Chinese teas and the risk of PD. Copyright © 2011 Elsevier Ltd. All rights reserved.

HIGHER SERUM CAFFEINE IN SMOKERS WITH SCHIZOPHRENIA COMPARED TO SMOKING CONTROLS

OpenAIRE

Gandhi, Kunal K; Williams, Jill M; Menza, Matthew; Galazyn, Magdalena; Benowitz, Neal L.

2010-01-01

Previous studies of high dietary caffeine intake in individuals with schizophrenia have not demonstrated biological evidence of higher intake or controlled smoking behavior. This study aimed to examine differences in serum caffeine levels in 104 smokers with schizophrenia/schizoaffective disorder (SCZ/SA) and compare them to 63 smokers without any mental illness (CON). Since we were interested in measuring caffeine levels, we excluded all non caffeine users from the study. Blood draws were st...

Adolescent habitual caffeine consumption and hemodynamic reactivity during rest, psychosocial stress, and recovery.

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James, Jack E; Baldursdottir, Birna; Johannsdottir, Kamilla R; Valdimarsdottir, Heiddis B; Sigfusdottir, Inga Dora

2018-07-01

Most adolescents regularly consume caffeine. Whereas observational studies have suggested that coffee may be cardio-protective, pharmacological experimentation with adults shows that caffeine at dietary doses increases blood pressure, thereby implicating regular caffeine consumption as a potential source of harm for cardiovascular health. The present study was in response to the dearth of caffeine research among younger consumers. It was hypothesised that compared to the consumption of little or no caffeine, adolescents who habitually consume caffeine have overall higher blood pressure and increased vascular resistance. Using a quasi-experimental design, continuous measurements of blood pressure, cardiac output, and total peripheral resistance were taken non-invasively from adolescents (n = 333) aged 14-15 years and 18-19 years who reported "low", "moderate", or "high" levels of caffeine intake. Measurements were conducted when participants generally had negligible or low systematic caffeine levels while at rest, during stress, and during recovery from stress. Whereas habitual caffeine consumption did not predict blood pressure level, higher caffeine intake was associated with modestly increased vascular resistance during all phases of the experiment (i.e., at rest, during stress, and during recovery from stress). Present findings are important because they suggest that early exposure to caffeine may lead to persistent increases in vascular resistance, which in turn is an acknowledged risk factor for the development of hypertension. These results highlight the need for further studies of adolescents to determine the robustness of any persistent caffeine-related hemodynamic effects, and the implications such effects could have for long-term cardiovascular health. Copyright © 2018 Elsevier Inc. All rights reserved.

[Caffeine--common ingredient in a diet and its influence on human health].

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Wierzejska, Regina

2012-01-01

Caffeine is widely consumed by people of all ages. In the last period a market of caffeine-containing products, particularly energy drinks and food supplements increased. Caffeine for years is under discussion, whether has positive whether adverse impact on health. Children are a group of special anxieties. Caffeine is a stimulant of central nervous system and therefore is probably the most commonly used psychoactive substance in the world. The physiological effect of caffeine and the lack of nutrition value causes a great interest its impact on health, especially with reference to the risk of cardiovascular diseases. Results of scientific research are not clear. The influence of caffeine on the human body is conditioned with the individual metabolism of caffeine which also depends on many endogenic and environmental factors. According to the current knowledge moderate caffeine intake by healthy adults at a dose level of 400 mg a day is not associated with adverse effects, but it also depends on other health determinants of a lifestyle. Excessive caffeine consumption can cause negative health consequences such as psychomotor agitation, insomnia, headache, gastrointestinal complaints. Adverse effect of caffeine intoxication is classified in World Health Organization's International Classification of Diseases (ICD-10). Metabolism of caffeine by pregnant woman is slowed down. Caffeine and its metabolites pass freely across the placenta into a fetus. For this reason pregnant women should limit caffeine intake. Children and adolescents should also limit daily caffeine consumption. It results from the influence of caffeine on the central nervous system in the period of rapid growth and the final stage of brain development, calcium balance and sleep duration. Average daily caffeine consumption in European countries ranging from 280-490 mg. The highest caffeine intake is in Scandinavian countries what results from the great consumption of the coffee. As far as caffeine

Interindividual Differences in Caffeine Metabolism and Factors Driving Caffeine Consumption.

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Nehlig, Astrid

2018-04-01

Most individuals adjust their caffeine intake according to the objective and subjective effects induced by the methylxanthine. However, to reach the desired effects, the quantity of caffeine consumed varies largely among individuals. It has been known for decades that the metabolism, clearance, and pharmacokinetics of caffeine is affected by many factors such as age, sex and hormones, liver disease, obesity, smoking, and diet. Caffeine also interacts with many medications. All these factors will be reviewed in the present document and discussed in light of the most recent data concerning the genetic variability affecting caffeine levels and effects at the pharmacokinetic and pharmacodynamic levels that both critically drive the level of caffeine consumption. The pharmacokinetics of caffeine are highly variable among individuals due to a polymorphism at the level of the CYP1A2 isoform of cytochrome P450, which metabolizes 95% of the caffeine ingested. Moreover there is a polymorphism at the level of another critical enzyme, N -acetyltransferase 2. At the pharmacodynamic level, there are several polymorphisms at the main brain target of caffeine, the adenosine A2A receptor or ADORA2. Genetic studies, including genome-wide association studies, identified several loci critically involved in caffeine consumption and its consequences on sleep, anxiety, and potentially in neurodegenerative and psychiatric diseases. We start reaching a better picture on how a multiplicity of biologic mechanisms seems to drive the levels of caffeine consumption, although much more knowledge is still required to understand caffeine consumption and effects on body functions. Copyright © 2018 by The American Society for Pharmacology and Experimental Therapeutics.

Reinforcing effects of caffeine in coffee and capsules.

Science.gov (United States)

Griffiths, R R; Bigelow, G E; Liebson, I A

1989-09-01

In a residential research ward the reinforcing and subjective effects of caffeine were studied under double-blind conditions in volunteer subjects with histories of heavy coffee drinking. In Experiment 1, 6 subjects had 13 opportunities each day to self-administer either a caffeine (100 mg) or a placebo capsule for periods of 14 to 61 days. All subjects developed a clear preference for caffeine, with intake of caffeine becoming relatively stable after preference had been attained. Preference for caffeine was demonstrated whether or not preference testing was preceded by a period of 10 to 37 days of caffeine abstinence, suggesting that a recent history of heavy caffeine intake (tolerance/dependence) was not a necessary condition for caffeine to function as a reinforcer. In Experiment 2, 6 subjects had 10 opportunities each day to self-administer a cup of coffee or (on different days) a capsule, dependent upon completing a work requirement that progressively increased and then decreased over days. Each day, one of four conditions was studied: caffeinated coffee (100 mg/cup), decaffeinated coffee, caffeine capsules (100 mg/capsule), or placebo capsules. Caffeinated coffee maintained the most self-administration, significantly higher than decaffeinated coffee and placebo capsules but not different from caffeine capsules. Both decaffeinated coffee and caffeine capsules were significantly higher than placebo capsules but not different from each other. In both experiments, subject ratings of "linking" of coffee or capsules covaried with the self-administration measures. These experiments provide the clearest demonstrations to date of the reinforcing effects of caffeine in capsules and in coffee.

Caffeine alters emotion and emotional responses in low habitual caffeine consumers.

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Giles, Grace E; Spring, Alexander M; Urry, Heather L; Moran, Joseph M; Mahoney, Caroline R; Kanarek, Robin B

2018-02-01

Caffeine reliably increases emotional arousal, but it is unclear whether and how it influences other dimensions of emotion such as emotional valence. These experiments documented whether caffeine influences emotion and emotion regulation choice and success. Low to abstinent caffeine consumers (maximum 100 mg/day) completed measures of state anxiety, positive and negative emotion, and salivary cortisol before, 45 min after, and 75 min after consuming 400 mg caffeine or placebo. Participants also completed an emotion regulation choice task, in which they chose to employ cognitive reappraisal or distraction in response to high and low intensity negative pictures (Experiment 1), or a cognitive reappraisal task, in which they employed cognitive reappraisal or no emotion regulation strategy in response to negative and neutral pictures (Experiment 2). State anxiety, negative emotion, and salivary cortisol were heightened both 45 and 75 min after caffeine intake relative to placebo. In Experiment 1, caffeine did not influence the frequency with which participants chose reappraisal or distraction, but reduced negativity of the picture ratings. In Experiment 2, caffeine did not influence cognitive reappraisal success. Thus, caffeine mitigated emotional responses to negative situations, but not how participants chose to regulate such responses or the success with which they did so.

Caffeine consumption among eating disorder patients: epidemiology, motivations, and potential of abuse.

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Burgalassi, A; Ramacciotti, C E; Bianchi, M; Coli, E; Polese, L; Bondi, E; Massimetti, G; Dell'osso, L

2009-12-01

Aim of the study was to investigate caffeine use in different types of eating disorders (ED) patients either using a categorical approach [Diagnostic and Statistical Manual of Mental Disorders - Fourth Edition - Text Revision (DSM-IV-TR) diagnostic criteria] or a dimensional perspective. Fifty-eight ED female patients [anorexia nervosa (AN), restricting and binge-eating/purging type, N=15; bulimia nervosa (BN) purging type/nonpurging type, N=26; binge eating disorder (BED), N=17] referred to an Eating Disorder Unit and 15 non-clinical controls were administered the Eating Disorder Inventory-2 (EDI-2), the Clinical Global Impression (CGI) and the Caffeine Use Test, an interview specifically developed to investigate caffeine intake. Statistical analyses were then repeated clustering patients according to the presence/absence of purging behaviors (purgers, N=22; non-purgers, N=19; BED, N=17). Current and lifetime caffeine use, measured as mg/day, were similar comparing controls and ED patients as a whole. BN patients showed a significantly higher maximum lifetime caffeine intake (817.4+/-528,9 vs 325.0+/-294.6 mg/die, F=3.246, pCaffeine abuse was significantly more represented among patients vs controls (pcaffeine, no significant difference was found among the different groups, for either Dependence, Intoxication or Withdrawal. Most of patients and controls reported pleasure as the main motivation for caffeine use, followed by increased vigilance and attention and appetite suppression in AN and BN patients. Note that a shift in diagnosis in the course of the ED from non-purging to purging type was associated with an increase in caffeine current, lifetime and maximum lifetime intake (F=1.667 pcaffeine intake in patients as a whole, but in the purging subgroup current caffeine use was increased in presence of an anxiety disorder (pcaffeine with an average intake similar to that of the general population, however with a kind of binge attitude. Among heavy drinkers, daily

Caffeine and energy drink use by combat arms soldiers in Afghanistan as a countermeasure for sleep loss and high operational demands.

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McLellan, Tom M; Riviere, Lyndon A; Williams, Kelly W; McGurk, Dennis; Lieberman, Harris R

2018-03-11

Combat deployments are characterized by high operational demands with limited opportunities for sleep leading to fatigue and degraded cognitive and operational performance. Caffeine in moderate doses is recognized as an effective intervention for physical and cognitive decrements associated with sleep loss. This report is based on data collected by two separate, independently conducted surveys administered in Afghanistan in 2011-2012. It assessed caffeine use and sleep disruption among U.S. Army combat soldiers (J-MHAT 8; n = 518) and among deployed soldiers with different military assignments (USARIEM Deployment Survey; n = 260). Daily caffeine intake assessed in the J-MHAT 8 survey averaged 404 ± 18 mg. In the USARIEM Deployment Survey, intake was 303 ± 29 mg and was significantly higher among combat arms soldiers (483 ± 100 mg) compared to combat service support personnel (235 ± 23 mg). In both surveys, over 55% of total caffeine intake was from energy drinks. Additional sources of caffeine included coffee, tea, sodas, gum, candy, and over-the-counter medications. Higher caffeine intake was not associated with ability to fall asleep at night or wake-up in the morning (J-MHAT 8 survey). Higher caffeine consumption was associated with disrupted sleep from high operational tempo and nighttime duties of combat operations. Overall caffeine consumption and energy drink use in Afghanistan was greater than among non-deployed soldiers and civilians. Caffeine was frequently used as a countermeasure during night operations to offset adverse effects of sleep loss on physical and cognitive function, consistent with current Department of the Army recommendations.

Associations of ambulatory blood pressure with urinary caffeine and caffeine metabolite excretions.

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Guessous, Idris; Pruijm, Menno; Ponte, Belén; Ackermann, Daniel; Ehret, Georg; Ansermot, Nicolas; Vuistiner, Philippe; Staessen, Jan; Gu, Yumei; Paccaud, Fred; Mohaupt, Markus; Vogt, Bruno; Pechère-Bertschi, Antoinette; Pechère-Berstchi, Antoinette; Martin, Pierre-Yves; Burnier, Michel; Eap, Chin B; Bochud, Murielle

2015-03-01

Intake of caffeinated beverages might be associated with reduced cardiovascular mortality possibly via the lowering of blood pressure. We estimated the association of ambulatory blood pressure with urinary caffeine and caffeine metabolites in a population-based sample. Families were randomly selected from the general population of Swiss cities. Ambulatory blood pressure monitoring was conducted using validated devices. Urinary caffeine, paraxanthine, theophylline, and theobromine excretions were measured in 24 hours urine using ultrahigh performance liquid chromatography tandem mass spectrometry. We used mixed models to explore the associations of urinary excretions with blood pressure although adjusting for major confounders. The 836 participants (48.9% men) included in this analysis had mean age of 47.8 and mean 24-hour systolic and diastolic blood pressure of 120.1 and 78.0 mm Hg. For each doubling of caffeine excretion, 24-hour and night-time systolic blood pressure decreased by 0.642 and 1.107 mm Hg (both P values theobromine excretion was not associated with blood pressure. Anti-hypertensive therapy, diabetes mellitus, and alcohol consumption modify the association of caffeine urinary excretion with systolic blood pressure. Ambulatory systolic blood pressure was inversely associated with urinary excretions of caffeine and other caffeine metabolites. Our results are compatible with a potential protective effect of caffeine on blood pressure. © 2014 American Heart Association, Inc.

Sources of Caffeine in Diets of US Children and Adults: Trends by Beverage Type and Purchase Location

Science.gov (United States)

Drewnowski, Adam; Rehm, Colin D.

2016-01-01

New sources of caffeine, besides coffee and tea, have been introduced into the US food supply. Data on caffeine consumption age and purchase location can help guide public health policy. National Health and Nutrition Examination Surveys (NHANES) were used to estimate population-level caffeine intakes, using data from 24-h dietary recall. First, caffeine intakes by age-group and beverage type were estimated using the most recent 2011–2012 data (n = 7456). Second, fourteen years trends in caffeine consumption, overall and by beverage type, were evaluated for adults and children. Trend analyses were conducted by age groups. Last, trends in caffeine intakes by purchase location and beverage type were estimated. In 2011–2012, children aged four to eight years consumed the least caffeine (15 mg/day), and adults aged 51–70 years consumed the most (213 mg/day). The population mean (age ≥ four years) was 135 mg/day, driven largely by coffee (90 mg/day), tea (25 mg/day), and soda (21 mg/day). For the 14–19 years and 20–34 years age-groups, energy drinks contributed 6 mg/day (9.9%) and 5 mg/day (4.5%), respectively. The bulk of caffeine came from store-bought coffee and tea. Among both children and adults combined, caffeine intakes declined from 175 mg/day (1999–2000) to 142 mg/day (2011–2012), largely driven by a drop in caffeine from soda (41 mg/day to 21 mg/day). Store-bought coffee and tea remain principal drivers of caffeine intake in the US. Sodas and energy drinks make minor contributions to overall caffeine intakes. PMID:26978391

Sources of Caffeine in Diets of US Children and Adults: Trends by Beverage Type and Purchase Location.

Science.gov (United States)

Drewnowski, Adam; Rehm, Colin D

2016-03-10

New sources of caffeine, besides coffee and tea, have been introduced into the US food supply. Data on caffeine consumption age and purchase location can help guide public health policy. National Health and Nutrition Examination Surveys (NHANES) were used to estimate population-level caffeine intakes, using data from 24-h dietary recall. First, caffeine intakes by age-group and beverage type were estimated using the most recent 2011-2012 data (n = 7456). Second, fourteen years trends in caffeine consumption, overall and by beverage type, were evaluated for adults and children. Trend analyses were conducted by age groups. Last, trends in caffeine intakes by purchase location and beverage type were estimated. In 2011-2012, children aged four to eight years consumed the least caffeine (15 mg/day), and adults aged 51-70 years consumed the most (213 mg/day). The population mean (age ≥ four years) was 135 mg/day, driven largely by coffee (90 mg/day), tea (25 mg/day), and soda (21 mg/day). For the 14-19 years and 20-34 years age-groups, energy drinks contributed 6 mg/day (9.9%) and 5 mg/day (4.5%), respectively. The bulk of caffeine came from store-bought coffee and tea. Among both children and adults combined, caffeine intakes declined from 175 mg/day (1999-2000) to 142 mg/day (2011-2012), largely driven by a drop in caffeine from soda (41 mg/day to 21 mg/day). Store-bought coffee and tea remain principal drivers of caffeine intake in the US. Sodas and energy drinks make minor contributions to overall caffeine intakes.

Sources of Caffeine in Diets of US Children and Adults: Trends by Beverage Type and Purchase Location

Directory of Open Access Journals (Sweden)

Adam Drewnowski

2016-03-01

Full Text Available New sources of caffeine, besides coffee and tea, have been introduced into the US food supply. Data on caffeine consumption age and purchase location can help guide public health policy. National Health and Nutrition Examination Surveys (NHANES were used to estimate population-level caffeine intakes, using data from 24-h dietary recall. First, caffeine intakes by age-group and beverage type were estimated using the most recent 2011–2012 data (n = 7456. Second, fourteen years trends in caffeine consumption, overall and by beverage type, were evaluated for adults and children. Trend analyses were conducted by age groups. Last, trends in caffeine intakes by purchase location and beverage type were estimated. In 2011–2012, children aged four to eight years consumed the least caffeine (15 mg/day, and adults aged 51–70 years consumed the most (213 mg/day. The population mean (age ≥ four years was 135 mg/day, driven largely by coffee (90 mg/day, tea (25 mg/day, and soda (21 mg/day. For the 14–19 years and 20–34 years age-groups, energy drinks contributed 6 mg/day (9.9% and 5 mg/day (4.5%, respectively. The bulk of caffeine came from store-bought coffee and tea. Among both children and adults combined, caffeine intakes declined from 175 mg/day (1999–2000 to 142 mg/day (2011–2012, largely driven by a drop in caffeine from soda (41 mg/day to 21 mg/day. Store-bought coffee and tea remain principal drivers of caffeine intake in the US. Sodas and energy drinks make minor contributions to overall caffeine intakes.

Validation of different instruments for caffeine measurement among premenopausal women in the BioCycle study.

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Schliep, Karen C; Schisterman, Enrique F; Mumford, Sunni L; Perkins, Neil J; Ye, Aijun; Pollack, Anna Z; Zhang, Cuilin; Porucznik, Christina A; VanDerslice, James A; Stanford, Joseph B; Wactawski-Wende, Jean

2013-04-01

Effects of caffeine on women's health are inconclusive, in part because of inadequate exposure assessment. In this study we determined 1) validity of a food frequency questionnaire compared with multiple 24-hour dietary recalls (24HDRs) for measuring monthly caffeine and caffeinated beverage intakes; and 2) validity of the 24HDR compared with the prior day's diary record for measuring daily caffeinated coffee intake. BioCycle Study (2005-2007) participants, women (n = 259) aged 18-44 years from western New York State, were followed for 2 menstrual cycles. Participants completed a food frequency questionnaire at the end of each cycle, four 24HDRs per cycle, and daily diaries. Caffeine intakes reported for the food frequency questionnaires were greater than those reported for the 24HDRs (mean = 114.1 vs. 92.6mg/day, P = 0.01) but showed high correlation (r = 0.73, P cups/day, P cup = 237 mL). Although caffeine and coffee exposures were highly correlated, absolute intakes differed significantly between measurement tools. These results highlight the importance of considering potential misclassification of caffeine exposure.

Beneficial effects of caffeine in a transgenic model of Alzheimer's disease-like tau pathology.

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Laurent, Cyril; Eddarkaoui, Sabiha; Derisbourg, Maxime; Leboucher, Antoine; Demeyer, Dominique; Carrier, Sébastien; Schneider, Marion; Hamdane, Malika; Müller, Christa E; Buée, Luc; Blum, David

2014-09-01

Tau pathology found in Alzheimer's disease (AD) is crucial in cognitive decline. Epidemiologic evidences support that habitual caffeine intake prevents memory decline during aging and reduces the risk to develop Alzheimer's disease. So far, experimental studies addressed the impact of caffeine in models mimicking the amyloid pathology of AD. However, in vivo effects of caffeine in a model of AD-like tauopathy remain unknown. Here, we evaluated effects of chronic caffeine intake (0.3 g/L through drinking water), given at an early pathologic stage, in the THY-Tau22 transgenic mouse model of progressive AD-like tau pathology. We found that chronic caffeine intake prevents from the development of spatial memory deficits in tau mice. Improved memory was associated with reduced hippocampal tau phosphorylation and proteolytic fragments. Moreover, caffeine treatment mitigated several proinflammatory and oxidative stress markers found upregulated in the hippocampus of THY-Tau22 animals. Together, our data support that moderate caffeine intake is beneficial in a model of AD-like tau pathology, paving the way for future clinical evaluation in AD patients. Copyright © 2014 Elsevier Inc. All rights reserved.

Reinforcing effects of caffeine in coffee and capsules.

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Griffiths, R R; Bigelow, G E; Liebson, I A

1989-01-01

In a residential research ward the reinforcing and subjective effects of caffeine were studied under double-blind conditions in volunteer subjects with histories of heavy coffee drinking. In Experiment 1, 6 subjects had 13 opportunities each day to self-administer either a caffeine (100 mg) or a placebo capsule for periods of 14 to 61 days. All subjects developed a clear preference for caffeine, with intake of caffeine becoming relatively stable after preference had been attained. Preference ...

The perinatal effects of maternal caffeine intake on fetal and neonatal brain levels of testosterone, estradiol, and dihydrotestosterone in rats.

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Karaismailoglu, S; Tuncer, M; Bayrak, S; Erdogan, G; Ergun, E L; Erdem, A

2017-08-01

Testosterone, estradiol, and dihydrotestosterone are the main sex steroid hormones responsible for the organization and sexual differentiation of brain structures during early development. The hypothalamo-pituitary-adrenocortical axis, adrenal cells, and gonads play a key role in the production of sex steroids and express adenosine receptors. Caffeine is a non-selective adenosine antagonist; therefore, it can modulate metabolic pathways in these tissues. Besides, the proportion of pregnant women that consume caffeine is ∼60%. That is why the relationship between maternal caffeine consumption and fetal development is important. Therefore, we aimed to investigate this modulatory effect of maternal caffeine consumption on sex steroids in the fetal and neonatal brain tissues. Pregnant rats were treated with a low (0.3 g/L) or high (0.8 g/L) dose of caffeine in their drinking water during pregnancy and lactation. The testosterone, estradiol, and dihydrotestosterone levels in the frontal cortex and hypothalamus were measured using radioimmunoassay at embryonic day 19 (E19), birth (PN0), and postnatal day 4 (PN4). The administration of low-dose caffeine increased the body weight in PN4 male and female rats and anogenital index in PN4 males. The administration of high-dose caffeine decreased the adrenal weight in E19 male rats and increased testosterone levels in the frontal cortex of E19 female rats and the hypothalamus of PN0 male rats. Maternal caffeine intake during pregnancy affects sex steroid levels in the frontal cortex and hypothalamus of the offspring. This concentration changes of the sex steroids in the brain may influence behavioral and neuroendocrine functions at some point in adult life.

Performance pressure and caffeine both affect cognitive performance, but likely through independent mechanisms.

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Boere, Julia J; Fellinger, Lizz; Huizinga, Duncan J H; Wong, Sebastiaan F; Bijleveld, Erik

2016-02-01

A prevalent combination in daily life, performance pressure and caffeine intake have both been shown to impact people's cognitive performance. Here, we examined the possibility that pressure and caffeine affect cognitive performance via a shared pathway. In an experiment, participants performed a modular arithmetic task. Performance pressure and caffeine intake were orthogonally manipulated. Findings indicated that pressure and caffeine both negatively impacted performance. However, (a) pressure vs. caffeine affected performance on different trial types, and (b) there was no hint of an interactive effect. So, though the evidence is indirect, findings suggest that pressure and caffeine shape performance via distinct mechanisms, rather than a shared one. Copyright © 2015 Elsevier Inc. All rights reserved.

Exploring an interaction of adenosine A2A receptor variability with coffee and tea intake in Parkinson's disease.

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Tan, E K; Lu, Z Y; Fook-Chong, S M C; Tan, E; Shen, H; Chua, E; Yih, Y; Teo, Y Y; Zhao, Y

2006-09-05

Caffeine is an adenosine receptor A1 and A2A receptor antagonist and a putative functional genetic variant of the A2A receptor (2592C > Tins) mediates caffeine-induced anxiety. Here we investigated the potential interaction of this A2A genetic variant with the quantity of coffee and tea intake and their relationship with the risk of PD. A total of 441 subjects consisting of 222 PD and 219 race, gender and age matched controls were included. A multivariate analysis of the variables including the 2592C > Tins A2A genotypes, age of onset, gender, and the quantity of tea and coffee intake, interaction of the A2A genotypes with coffee intake, interaction of A2A genotypes with tea intake demonstrated the quantity of coffee intake to be significantly associated with PD (P coffee and tea intake in modulating the risk of PD. The dose dependent protective effect of coffee intake in PD was independent of the 2592C > Tins A2A genotype suggesting that the pharmacogenetic action of caffeine in PD may be mediated differently from other caffeine-induced neurologic syndromes.

The Janus face of caffeine.

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Porciúncula, Lisiane O; Sallaberry, Cássia; Mioranzza, Sabrina; Botton, Paulo Henrique S; Rosemberg, Denis B

2013-11-01

Caffeine is certainly the psychostimulant substance most consumed worldwide. Over the past years, chronic consumption of caffeine has been associated with prevention of cognitive decline associated to aging and mnemonic deficits of brain disorders. While its preventive effects have been reported extensively, the cognitive enhancer properties of caffeine are relatively under debate. Surprisingly, there are scarce detailed ontogenetic studies focusing on neurochemical parameters related to the effects of caffeine during prenatal and earlier postnatal periods. Furthermore, despite the large number of epidemiological studies, it remains unclear how safe is caffeine consumption during pregnancy and brain development. Thus, the purpose of this article is to review what is currently known about the actions of caffeine intake on neurobehavioral and adenosinergic system during brain development. We also reviewed other neurochemical systems affected by caffeine, but not only during brain development. Besides, some recent epidemiological studies were also outlined with the control of "pregnancy signal" as confounding variable. The idea is to tease out how studies on the impact of caffeine consumption during brain development deserve more attention and further investigation. Copyright © 2013 Elsevier Ltd. All rights reserved.

Caffeine exposure during rat brain development causes memory impairment in a sex selective manner that is offset by caffeine consumption throughout life.

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Ardais, Ana Paula; Rocha, Andréia S; Borges, Maurício Felisberto; Fioreze, Gabriela T; Sallaberry, Cássia; Mioranzza, Sabrina; Nunes, Fernanda; Pagnussat, Natália; Botton, Paulo Henrique S; Cunha, Rodrigo A; Porciúncula, Lisiane de Oliveira

2016-04-15

Caffeine is the psychostimulant most consumed worldwide. In moderate doses, it affords a beneficial effect in adults and upon aging, but has a deleterious effect during brain development. We now tested if caffeine consumption by rats (0.1, 0.3, 1.0 g/L in the drinking water, only during active cycle and weekdays) during adulthood could revert the potentially negative effects of caffeine during early life. Thus, we compared caffeine intake starting 15 days before mating and lasting either up to weaning (development) or up to adulthood, on behavior and synaptic proteins in male and female rats. Recognition memory was impaired only in female rats receiving caffeine (0.3 and 1.0 g/L) during development, coincident with increased proBDNF and unchanged BDNF levels in the hippocampus. Caffeine in both treatment regimens caused hyperlocomotion only in male rats, whereas anxiety-related behavior was attenuated in both sexes by caffeine (1.0 g/L) throughout life. Both caffeine treatment regimens decreased GFAP (as an astrocyte marker) and SNAP-25 (as a nerve terminals marker) in the hippocampus from male rats. TrkB receptor was decreased in the hippocampus from both sexes and treatment regimens. These findings revealed that caffeine intake during a specific time window of brain development promotes sex-dependent behavioral outcomes related to modification in BDNF signaling. Furthermore, caffeine throughout life can overcome the deleterious effects of caffeine on recognition memory during brain development in female rats. Copyright © 2016 Elsevier B.V. All rights reserved.

Prospective study of caffeine consumption and risk of Parkinson's disease in men and women.

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Ascherio, A; Zhang, S M; Hernán, M A; Kawachi, I; Colditz, G A; Speizer, F E; Willett, W C

2001-07-01

Results of case-control studies and of a prospective investigation in men suggest that consumption of coffee could protect against the risk of Parkinson's disease, but the active constituent is not clear. To address the hypothesis that caffeine is protective against Parkinson's disease, we examined the relationship of coffee and caffeine consumption to the risk of this disease among participants in two ongoing cohorts, the Health Professionals' Follow-Up Study (HPFS) and the Nurses' Health Study (NHS). The study population comprised 47,351 men and 88,565 women who were free of Parkinson's disease, stroke, or cancer at baseline. A comprehensive life style and dietary questionnaire was completed by the participants at baseline and updated every two to four years. During the follow-up (10 years in men, 16 years in women), we documented a total of 288 incident cases of Parkinson's disease. Among men, after adjustment for age and smoking, the relative risk of Parkinson's disease was 0.42 (95% CI: 0.23-0.78; p for trend coffee (p for trend = 0.004), caffeine from noncoffee sources (p for trend coffee. Among women, the relationship between caffeine or coffee intake and risk of Parkinson's disease was U-shaped, with the lowest risk observed at moderate intakes (1-3 cups of coffee/day, or the third quintile of caffeine consumption). These results support a possible protective effect of moderate doses of caffeine on risk of Parkinson's disease.

Levels of caffeine and its metabolites among U.S. smokers and nonsmokers.

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Jain, Ram B

2015-03-01

Data from National Health and Nutrition Examination Survey for the years 2009-2010 were used to estimate the levels of caffeine and 14 of its metabolite among U.S. smokers and nonsmokers after adjustments were made for other factors that affect observed caffeine levels. In this study, when adjusted for daily caffeine intake, adjusted levels (AGM) of caffeine and its metabolites were not found to be statistically significantly different between smokers and nonsmokers. AGMs for caffeine and all of its metabolites were found to be statistically significantly higher (p whites > Hispanics > non-Hispanic blacks and most of the differences were statistically significant, at least between non-Hispanic whites and non-Hispanic blacks (p < 0.01). In general, there was a statistically significant positive association between the levels of caffeine and its metabolites and body mass index as well as daily caffeine intake. However, the levels of 7-methylxanthine were negatively associated with body mass index. Copyright © 2015 Elsevier B.V. All rights reserved.

Caffeine and risk of Parkinson disease in a large cohort of men and women

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Palacios, Natalia; Gao, Xiang; McCullough, Marjorie L.; Schwarzschild, Michael A.; Shah, Roma; Gapstur, Susan; Ascherio, Alberto

2012-01-01

Background Caffeine consumption has been associated with a reduced risk of Parkinson disease. The association is strong and consistent in men, but uncertain in women, possibly because of an interaction with hormone replacement therapy. We sought to confirm these findings using data on Parkinson disease incidence in the CPS II Nutrition Cohort, a large prospective study of men and women. Methods We conducted a prospective study of caffeine intake and risk of PD within the Cancer Prevention Study II Nutrition Cohort. Intakes of coffee and other sources of caffeine were assessed at baseline. Incident cases of PD (n = 317; 197 men and 120 women) were confirmed by treating physicians and medical record review. Relative risks (RR) were estimated using proportional hazards models, adjusting for age, smoking and alcohol consumption. Results After adjustment for age, smoking and alcohol intake, high caffeine consumption was associated with a reduced risk of PD. The relative risk comparing the 5th to the 1st quintile of caffeine intake was 0.43 (CI: 0.26, 0.71, p-trend = coffee was not associated with PD risk. Conclusion Findings from this large prospective study of men and women are consistent with a protective effect of caffeine intake on PD incidence, with an attenuating influence of hormone replacement therapy in women. PMID:22927157

Caffeine and risk of Parkinson's disease in a large cohort of men and women.

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Palacios, Natalia; Gao, Xiang; McCullough, Marjorie L; Schwarzschild, Michael A; Shah, Roma; Gapstur, Susan; Ascherio, Alberto

2012-09-01

Caffeine consumption has been associated with a reduced risk of Parkinson's disease (PD). The association is strong and consistent in men, but uncertain in women, possibly because of an interaction with hormone replacement therapy (HRT). We sought to confirm these findings using data on PD incidence in the Cancer Prevention Study II Nutrition Cohort (CPS II-Nutrition), a large, prospective study of men and women. We conducted a prospective study of caffeine intake and risk of PD within the CPS II Nutrition Cohort. Intakes of coffee and other sources of caffeine were assessed at baseline. Incident cases of PD (n = 317; 197 men and 120 women) were confirmed by treating physicians and medical record review. Relative risks (RRs) were estimated using proportional hazards models, adjusting for age, smoking, and alcohol consumption. After adjustment for age, smoking, and alcohol intake, high caffeine consumption was associated with a reduced risk of PD. The RR comparing the 5th to the 1st quintile of caffeine intake was 0.43 (95% confidence interval [CI]: 0.26, 0.71; P trend = coffee was not associated with PD risk. Findings from this large, prospective study of men and women are consistent with a protective effect of caffeine intake on PD incidence, with an attenuating influence of HRT in women. © 2012 Movement Disorder Society. Copyright © 2012 Movement Disorder Society.

Espresso coffees, caffeine and chlorogenic acid intake: potential health implications.

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Crozier, Thomas W M; Stalmach, Angelique; Lean, Michael E J; Crozier, Alan

2012-01-01

HPLC analysis of 20 commercial espresso coffees revealed 6-fold differences in caffeine levels, a 17-fold range of caffeoylquinic acid contents, and 4-fold differences in the caffeoylquinic acid : caffeine ratio. These variations reflect differences in batch-to-batch bean composition, possible blending of arabica with robusta beans, as well as roasting and grinding procedures, but the predominant factor is likely to be the amount of beans used in the coffee-making/barista processes. The most caffeine in a single espresso was 322 mg and a further three contained >200 mg, exceeding the 200 mg day(-1) upper limit recommended during pregnancy by the UK Food Standards Agency. This snap-shot of high-street expresso coffees suggests the published assumption that a cup of strong coffee contains 50 mg caffeine may be misleading. Consumers at risk of toxicity, including pregnant women, children and those with liver disease, may unknowingly ingest excessive caffeine from a single cup of espresso coffee. As many coffee houses prepare larger volume coffees, such as Latte and Cappuccino, by dilution of a single or double shot of expresso, further study on these products is warranted. New data are needed to provide informative labelling, with attention to bean variety, preparation, and barista methods.

J-difference-edited MRS measures of γ-aminobutyric acid before and after acute caffeine administration.

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Oeltzschner, Georg; Zöllner, Helge J; Jonuscheit, Marc; Lanzman, Rotem S; Schnitzler, Alfons; Wittsack, Hans-Jörg

2018-05-12

The aim of this study was to investigate potential effects of acute caffeine intake on J-difference-edited MRS measures of the primary inhibitory neurotransmitter γ-aminobutyric acid (GABA). J-difference-edited Mescher-Garwood PRESS (MEGA-PRESS) and conventional PRESS data were acquired at 3T from voxels in the anterior cingulate and occipital area of the brain in 15 healthy subjects, before and after oral intake of a 200-mg caffeine dose. MEGA-PRESS data were analyzed with the MATLAB-based Gannet tool to estimate GABA+ macromolecule (GABA+) levels, while PRESS data were analyzed with LCModel to estimate levels of glutamate, glutamate+glutamine, N-acetylaspartate, and myo-inositol. All metabolites were quantified with respect to the internal reference compounds creatine and tissue water, and compared between the pre- and post-caffeine intake condition. For both MRS voxels, mean GABA+ estimates did not differ before and after caffeine intake. Slightly lower estimates of myo-inositol were observed after caffeine intake in both voxels. N-acetylaspartate, glutamate, and glutamate+glutamine did not show significant differences between conditions. Mean GABA+ estimates from J-difference-edited MRS in two different brain regions are not altered by acute oral administration of caffeine. These findings may increase subject recruitment efficiency for MRS studies. © 2018 International Society for Magnetic Resonance in Medicine.

Caffeine triggers behavioral and neurochemical alterations in adolescent rats.

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Ardais, A P; Borges, M F; Rocha, A S; Sallaberry, C; Cunha, R A; Porciúncula, L O

2014-06-13

Caffeine is the psychostimulant most consumed worldwide but concerns arise about the growing intake of caffeine-containing drinks by adolescents since the effects of caffeine on cognitive functions and neurochemical aspects of late brain maturation during adolescence are poorly known. We now studied the behavioral impact in adolescent male rats of regular caffeine intake at low (0.1mg/mL), moderate (0.3mg/mL) and moderate/high (1.0mg/mL) doses only during their active period (from 7:00 P.M. to 7:00 A.M.). All tested doses of caffeine were devoid of effects on locomotor activity, but triggered anxiogenic effects. Caffeine (0.3 and 1mg/mL) improved the performance in the object recognition task, but the higher dose of caffeine (1.0mg/mL) decreased the habituation to an open-field arena, suggesting impaired non-associative memory. All tested doses of caffeine decreased the density of glial fibrillary acidic protein and synaptosomal-associated protein-25, but failed to modify neuron-specific nuclear protein immunoreactivity in the hippocampus and cerebral cortex. Caffeine (0.3-1mg/mL) increased the density of brain-derived neurotrophic factor (BDNF) and proBDNF density as well as adenosine A1 receptor density in the hippocampus, whereas the higher dose of caffeine (1mg/mL) increased the density of proBDNF and BDNF and decreased A1 receptor density in the cerebral cortex. These findings document an impact of caffeine consumption in adolescent rats with a dual impact on anxiety and recognition memory, associated with changes in BDNF levels and decreases of astrocytic and nerve terminal markers without overt neuronal damage in hippocampal and cortical regions. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

Sources of Caffeine in Diets of US Children and Adults: Trends by Beverage Type and Purchase Location

OpenAIRE

Adam Drewnowski; Colin D. Rehm

2016-01-01

New sources of caffeine, besides coffee and tea, have been introduced into the US food supply. Data on caffeine consumption age and purchase location can help guide public health policy. National Health and Nutrition Examination Surveys (NHANES) were used to estimate population-level caffeine intakes, using data from 24-h dietary recall. First, caffeine intakes by age-group and beverage type were estimated using the most recent 2011?2012 data (n = 7456). Second, fourteen years trends in caffe...

ASSOCIATION OF CAFFEINE INTAKE AND LIVER FIBROSIS IN PATIENTS WITH CHRONIC HEPATITIS C

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Kalinca da Silva OLIVEIRA

2015-03-01

Full Text Available Background Caffeine consumption has been associated to decreased levels of liver enzymes and lower risk of fibrosis in patients with hepatitis C virus. Objectives This study aimed to evaluate the association between caffeine consumption and inflammatory activity or degree of liver fibrosis in patients with hepatitis C virus infection. Methods A cross-sectional study of patients with chronic hepatitis C virus infection treated in an outpatient Gastroenterology Unit of Santa Casa Hospital (Porto Alegre - Brasil. Patients were interviewed regarding the consumption of caffeine and anthropometric assessment was performed. Liver biopsy was performed in a maximum period of 36 months before inclusion in the study Results There were 113 patients, 67 (59.3% females, 48 (42.5% were aged between 52 and 62 years, and 101 (89.4% were white. The average caffeine consumption was 251.41 ± 232.32 mg/day, and 70 (62% patients consumed up to 250 mg/day of caffeine. There was no association between caffeine consumption and inflammatory activity on liver biopsy. On the other hand, when evaluating the caffeine consumption liver fibrosis an inverse association was observed. Conclusions The greater consumption of caffeine was associated with lower liver fibrosis. There was no association between caffeine consumption and inflammatory activity.

Withdrawal syndrome after the double-blind cessation of caffeine consumption.

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Silverman, K; Evans, S M; Strain, E C; Griffiths, R R

1992-10-15

People who stop consuming caffeine may have symptoms, but the incidence and severity of caffeine withdrawal are not known. This study was performed to determine the effects in the general population of ending one's dietary intake of caffeine. We studied 62 normal adults whose intake of caffeine was low to moderate (mean amount, 235 mg--the equivalent of 2.5 cups of coffee--per day). They completed questionnaires about symptoms and tests of their mood and performance when consuming their normal diets (base-line period) and at the end of each of two two-day periods during which they consumed caffeine-free diets and under double-blind conditions received capsules containing placebo (placebo period) or caffeine (caffeine period) in amounts equal to their daily caffeine consumption. More subjects had abnormally high Beck Depression Inventory scores (11 percent), high scores on the trait scale of the State-Trait Anxiety Inventory (8 percent), low vigor scores (11 percent) and high fatigue scores (8 percent) on the Profile of Mood States, and moderate or severe headache (52 percent) during the placebo period than during either the base-line period (2, 0, 0, 0, and 2 percent, respectively; P less than 0.05) or the caffeine period (3, 2, 2, 0, and 6 percent; P less than 0.05). More subjects reported unauthorized use of medications during the placebo period (13 percent) than during the caffeine period (2 percent, P = 0.017). Performance of a tapping task was slower during the placebo period than during the base-line and caffeine periods (P less than 0.01). Persons who consume low or moderate amounts of caffeine may have a withdrawal syndrome after their daily consumption of caffeine ceases.

Caffeine tolerance: behavioral, electrophysiological and neurochemical evidence

International Nuclear Information System (INIS)

Chou, D.T.; Khan, S.; Forde, J.; Hirsh, K.R.

1985-01-01

The development of tolerance to the stimulatory action of caffeine upon mesencephalic reticular neurons and upon spontaneous locomotor activity was evaluated in rats after two weeks of chronic exposure to low doses of caffeine (5-10 mg/kg/day via their drinking water). These doses are achievable through dietary intake of caffeine-containing beverages in man. Concomitant measurement of [ 3 H]-CHA binding in the mesencephalic reticular formation was also carried out in order to explore the neurochemical basis of the development of tolerance. Caffeine, 2.5 mg/kg i.v., markedly increased the firing rate of reticular neurons in caffeine naive rats but failed to modify the neuronal activity in a group exposed chronically to low doses of caffeine. In addition, in spontaneous locomotor activity studies, the data show a distinct shift to the right of the caffeine dose-response curve in caffeine pretreated rats. These results clearly indicate that tolerance develops to the stimulatory action of caffeine upon the reticular formation at the single neuronal activity level as well as upon spontaneous locomotor activity. Furthermore, in chronically caffeine exposed rats, an increase in the number of binding sites for [ 3 H]-CHA was observed in reticular formation membranes without any change in receptor affinity. 28 references, 4 figures

The Safety of Ingested Caffeine: A Comprehensive Review

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Jennifer L. Temple

2017-05-01

Full Text Available Caffeine is the most widely consumed psychoactive drug in the world. Natural sources of caffeine include coffee, tea, and chocolate. Synthetic caffeine is also added to products to promote arousal, alertness, energy, and elevated mood. Over the past decade, the introduction of new caffeine-containing food products, as well as changes in consumption patterns of the more traditional sources of caffeine, has increased scrutiny by health authorities and regulatory bodies about the overall consumption of caffeine and its potential cumulative effects on behavior and physiology. Of particular concern is the rate of caffeine intake among populations potentially vulnerable to the negative effects of caffeine consumption: pregnant and lactating women, children and adolescents, young adults, and people with underlying heart or other health conditions, such as mental illness. Here, we review the research into the safety and safe doses of ingested caffeine in healthy and in vulnerable populations. We report that, for healthy adults, caffeine consumption is relatively safe, but that for some vulnerable populations, caffeine consumption could be harmful, including impairments in cardiovascular function, sleep, and substance use. We also identified several gaps in the literature on which we based recommendations for the future of caffeine research.

Pulse waveform analysis on temporal changes in ocular blood flow due to caffeine intake: a comparative study between habitual and non-habitual groups.

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Ismail, Aishah; Bhatti, Mehwish S; Faye, Ibrahima; Lu, Cheng Kai; Laude, Augustinus; Tang, Tong Boon

2018-06-06

To evaluate and compare the temporal changes in pulse waveform parameters of ocular blood flow (OBF) between non-habitual and habitual groups due to caffeine intake. This study was conducted on 19 healthy subjects (non-habitual 8; habitual 11), non-smoking and between 21 and 30 years of age. Using laser speckle flowgraphy (LSFG), three areas of optical nerve head were analyzed which are vessel, tissue, and overall, each with ten pulse waveform parameters, namely mean blur rate (MBR), fluctuation, skew, blowout score (BOS), blowout time (BOT), rising rate, falling rate, flow acceleration index (FAI), acceleration time index (ATI), and resistive index (RI). Two-way mixed ANOVA was used to determine the difference between every two groups where p groups in several ocular pulse waveform parameters, namely MBR (overall, vessel, tissue), BOT (overall), rising rate (overall), and falling rate (vessel), all with p group, but not within the habitual group. The temporal changes in parameters MBR (vessel, tissue), skew (overall, vessel), BOT (overall, vessel), rising rate (overall), falling rate (overall, vessel), and FAI (tissue) were significant for both groups (habitual and non-habitual) in response to caffeine intake. The experiment results demonstrated caffeine does modulate OBF significantly and response differently in non-habitual and habitual groups. Among all ten parameters, MBR and BOT were identified as the suitable biomarkers to differentiate between the two groups.

Metabolic and hormonal effects of caffeine: randomized, double-blind, placebo-controlled crossover trial.

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MacKenzie, Todd; Comi, Richard; Sluss, Patrick; Keisari, Ronit; Manwar, Simone; Kim, Janice; Larson, Robin; Baron, John A

2007-12-01

In short-term studies, caffeine has been shown to increase insulin levels, reduce insulin sensitivity, and increase cortisol levels. However, epidemiological studies have indicated that long-term consumption of beverages containing caffeine such as coffee and green tea is associated with a reduced risk of type 2 diabetes mellitus. There is a paucity of randomized studies addressing the metabolic and hormonal effects of consuming caffeine over periods of more than 1 day. We evaluated the effect of oral intake of 200 mg of caffeine taken twice a day for 7 days on glucose metabolism, as well as on serum cortisol, dehydroepiandrosterone (DHEA), and androstenedione, and on nighttime salivary melatonin. A double-blind, randomized, placebo-controlled crossover study with periods of 7 days and washouts of 5 days comparing caffeine with placebo capsules was conducted. Participants were 16 healthy adults aged 18 to 22 years with a history of caffeine consumption. Blood samples from each subject were assayed for glucose, insulin, serum cortisol, DHEA, and androstenedione on the eighth day of each period after an overnight fast. Nighttime salivary melatonin was also measured. Insulin levels were significantly higher (by 1.80 microU/mL; 95% confidence interval, 0.33-3.28) after caffeine intake than after placebo. The homeostasis model assessment index of insulin sensitivity was reduced by 35% (95% confidence interval, 7%-62%) by caffeine. There were no differences in glucose, DHEA, androstenedione, and melatonin between treatment periods. This study provides evidence that daily caffeine intake reduces insulin sensitivity; the effect persists for at least a week and is evident up to 12 hours after administration.

Effects of the Interaction of Caffeine and Water on Voice Performance: A Pilot Study

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Franca, Maria Claudia; Simpson, Kenneth O.

2013-01-01

The objective of this "pilot" investigation was to study the effects of the interaction of caffeine and water intake on voice as evidenced by acoustic and aerodynamic measures, to determine whether ingestion of 200 mg of caffeine and various levels of water intake have an impact on voice. The participants were 48 females ranging in age…

Estimating caffeine intake from energy drinks and dietary supplements in the United States.

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Bailey, Regan L; Saldanha, Leila G; Gahche, Jaime J; Dwyer, Johanna T

2014-10-01

No consistent definition exists for energy products in the United States. These products have been marketed and sold as beverages (conventional foods), energy shots (dietary supplements), and in pill or tablet form. Recently, the number of available products has surged, and formulations have changed to include caffeine. To help characterize the use of caffeine-containing energy products in the United States, three sources of data were analyzed: sales data, data from federal sources, and reports from the Drug Abuse Warning Network. These data indicate that sales of caffeine-containing energy products and emergency room visits involving their consumption appear to be increasing over time. Data from the National Health and Nutrition Examination Survey (NHANES) 2007-2010 indicate that 2.7% [standard error (SE) 0.2%] of the US population ≥1 year of age used a caffeine-containing energy product, providing approximately 150-200 mg/day of caffeine per day in addition to caffeine from traditional sources like coffee, tea, and colas. The highest usage of these products was among males between the ages of 19 and 30 years (7.6%, SE 1.0). Although the prevalence of caffeine-containing energy product use remains low overall in the US population, certain subgroups appear to be using these products in larger amounts. Several challenges remain in determining the level of caffeine exposure from and accurate usage patterns of caffeine-containing energy products. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

Contribution of caffeine to the homocysteine-raising effect of coffee: a randomized controlled trial in humans.

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Verhoef, Petra; Pasman, Wilrike J; Van Vliet, Trinette; Urgert, Rob; Katan, Martijn B

2002-12-01

A high plasma total homocysteine concentration is associated with increased risk of cardiovascular disease. Consumption of unfiltered or filtered coffee raises total homocysteine concentrations in healthy volunteers. The responsible compound, however, is unknown. The objective was to determine whether caffeine explains the homocysteine-raising effect of coffee. Forty-eight subjects aged 19-65 y completed this randomized crossover study with 3 treatments, each lasting 2 wk. Subjects consumed 6 capsules providing 870 mg caffeine/d (test treatment), 0.9 L paper-filtered coffee providing approximately 870 mg caffeine/d, or 6 placebo capsules. Blood samples were drawn fasting and 4 h after consumption of 0.45 L coffee or 3 capsules. The mean fasting plasma homocysteine concentration after the placebo treatment was 9.6 +/- 3.1 micro mol/L. The caffeine and coffee treatments increased fasting homocysteine by 0.4 micro mol/L (95% CI: 0.1, 0.7; P = 0.04), or 5%, and by 0.9 micro mol/L (95% CI: 0.6, 1.2; P = 0.0001), or 11%, respectively, compared with placebo. The increase in homocysteine concentrations 4 h after consumption of 0.45 L coffee relative to consumption of 3 placebo capsules was 19% (P = 0.0001). Caffeine treatment had a much weaker acute effect on homocysteine (4%; P = 0.09). Effects of caffeine were stronger in women than in men, but the effects of coffee did not differ significantly between men and women. Caffeine is partly responsible for the homocysteine-raising effect of coffee. Coffee, but not caffeine, affects homocysteine metabolism within hours after intake, although the effect is still substantial after an overnight fast.

Influence of caffeine on blood pressure and platelet aggregation

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José Wilson S. Cavalcante

2000-08-01

Full Text Available OBJECTIVE: Studies have demonstrated that methylxanthines, such as caffeine, are A1 and A2 adenosine receptor antagonists found in the brain, heart, lungs, peripheral vessels, and platelets. Considering the high consumption of products with caffeine in their composition, in Brazil and throughout the rest of the world, the authors proposed to observe the effects of this substance on blood pressure and platelet aggregation. METHODS: Thirteen young adults, ranging from 21 to 27 years of age, participated in this study. Each individual took 750mg/day of caffeine (250mg tid, over a period of seven days. The effects on blood pressure were analyzed through the pressor test with handgrip, and platelet aggregation was analyzed using adenosine diphosphate, collagen, and adrenaline. RESULTS: Diastolic pressure showed a significant increase 24 hours after the first intake (p<0.05. This effect, however, disappeared in the subsequent days. The platelet aggregation tests did not reveal statistically significant alterations, at any time during the study. CONCLUSION: The data suggest that caffeine increases diastolic blood pressure at the beginning of caffeine intake. This hypertensive effect disappears with chronic use. The absence of alterations in platelet aggregation indicates the need for larger randomized studies.

Caffeine differentially alters cortical hemodynamic activity during working memory: a near infrared spectroscopy study.

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Heilbronner, Urs; Hinrichs, Hermann; Heinze, Hans-Jochen; Zaehle, Tino

2015-10-01

Caffeine is a widely used stimulant with potentially beneficial effects on cognition as well as vasoconstrictive properties. In functional magnetic imaging research, caffeine has gained attention as a potential enhancer of the blood oxygenation level-dependent (BOLD) response. In order to clarify changes of oxy- and deoxyhemoglobin (HbO and HbR) induced by caffeine during a cognitive task, we investigated a working memory (WM) paradigm (visual 2-back) using near-infrared spectroscopy (NIRS). Behaviorally, caffeine had no effect on the WM performance but influenced reaction times in the 0-back condition. NIRS data demonstrate caffeine-dependent alterations of the course of the hemodynamic response. The intake of 200 mg caffeine caused a significant decrease of the HbO response between 20 and 40 s after the onset of a 2-back task in the bilateral inferior frontal cortex (IFC). In parallel, the HbR response of the left IFC was significantly increased due to caffeine intake. In line with previous results, we did not detect an effect of caffeine on most aspects of behavior. Effects of caffeine on brain vasculature were detected as general reduction of HbO. Neuronal effects of caffeine are reflected in an increased concentration of HbR in the left hemisphere when performing a verbal memory task and suggest influences on metabolism.

In adolescence a higher 'eveningness in energy intake' is associated with higher total daily energy intake.

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Diederichs, Tanja; Perrar, Ines; Roßbach, Sarah; Alexy, Ute; Buyken, Anette E

2018-05-26

The present manuscript addressed two hypotheses: (i) As children age, energy intake is shifted from morning (energy intake energy intake >6pm) (ii) A higher 'eveningness in energy intake' (i.e. evening minus morning energy intake) is associated with a higher total daily energy intake. Data were analyzed from 262 DONALD cohort study participants, who had completed at least one 3-day weighed dietary record in the age groups 3/4, 5/6, 7/8, 9/10, 11/12, 13/14, 15/16 and 17/18 years (y). 'Eveningness in energy intake' was compared across age groups and related to total daily energy intake for each age group (multiple cross-sectional analyses). 'Eveningness' increased progressively from age group 3/4y to age group 17/18y. A median surplus of evening energy intake (i.e. when evening intake exceeded morning intake) was firstly observed for age group 11/12y. From age group 11/12y onwards, a higher 'eveningness' was associated with a higher total daily energy intake (all p energy intake between the highest and the lowest tertile of 'eveningness' was largest for age group 17/18y, amounting to an 11% higher intake among adolescents in the highest as compared to those in the lowest tertile. In conclusion, energy intake progressively shifts from morning to evening hours as children age. Once evening energy intake exceeds morning energy intake, a higher 'eveningness in energy intake' is associated with higher total daily energy intake. Copyright © 2018 Elsevier Ltd. All rights reserved.

Changes in Intakes of Total and Added Sugar and their Contribution to Energy Intake in the U.S.

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Won O. Song

2010-08-01

Full Text Available This study was designed to document changes in total sugar intake and intake of added sugars, in the context of total energy intake and intake of nutrient categories, between the 1970s and the 1990s, and to identify major food sources contributing to those changes in intake. Data from the NHANES I and III were analyzed to obtain nationally representative information on food consumption for the civilian, non-institutionalized population of the U.S. from 1971 to 1994. In the past three decades, in addition to the increase in mean intakes of total energy, total sugar, added sugars, significant increases in the total intake of carbohydrates and the proportion of carbohydrates to the total energy intake were observed. The contribution of sugars to total carbohydrate intake decreased in both 1–18 y and 19+ y age subgroups, and the contribution of added sugars to the total energy intake did not change. Soft drinks/fluid milk/sugars and cakes, pastries, and pies remained the major food sources for intake of total sugar, total carbohydrates, and total energy during the past three decades. Carbonated soft drinks were the most significant sugar source across the entire three decades. Changes in sugar consumption over the past three decades may be a useful specific area of investigation in examining the effect of dietary patterns on chronic diseases.

Does caffeine affect cardiovascular responses?

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S. Bradamante; L. Barenghi (Livia); S. Versari (Silvia); A. Villa (Alessandro); J.W. de Jong (Jan Willem)

2007-01-01

textabstractCaffeine (1,3,7-trimethylxanthine), a natural alkaloid present in many beverages such as coffee, tea and cola drinks, is the most widely consumed pharmacological compound. Due to its common use and frequent intake in stressful conditions, a great deal of data have been produced by

Habitual caffeine consumption and its relation to memory, attention, planning capacity and psychomotor performance across multiple age groups.

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Hameleers, P. A. H. M; Van Boxtel, M. P. J; Hogervorst, E; Riedel, W. J; Houx, P. J; Buntinx, F; Jolles, J

2000-12-01

The present study evaluated the association between habitual caffeine intake via coffee and tea and cognitive performance. This was done as part of a larger research programme into the determinants of cognitive ageing (the Maastricht Aging Study: MAAS). Possible withdrawal effects that may have explained in part the positive association between performance and intake in an earlier study were controlled for. In addition, all cognitive tests in this study were administered under strict laboratory conditions. A group of 1875 healthy adults, stratified for age (range 24 - 81 years), sex, and general ability, were screened for habitual intake of coffee and tea and took part in extensive cognitive testing. Multiple regression analysis with control for age, sex, socio-demographic variables, and substance use showed that habitual caffeine consumption was significantly related to better long-term memory performance and faster locomotor speed. No relationships were found between habitual caffeine consumption and short-term memory, information processing, planning, and attention as measured with the Stroop Test. Moreover, no difference in sensitivity to caffeine intake between different age groups was found, suggesting that caffeine intake did not counteract age-related cognitive decline. Several recommendations are made to improve the design of future studies in this field. Copyright 2000 John Wiley & Sons, Ltd.

Psychostimulant and other effects of caffeine in 9- to 11-year-old children.

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Heatherley, Susan V; Hancock, Katie M F; Rogers, Peter J

2006-02-01

Recent research on adults suggests that "beneficial" psychostimulant effects of caffeine are found only in the context of caffeine deprivation; that is, caffeine improves psychomotor and cognitive performance in habitual caffeine consumers following caffeine withdrawal. Furthermore, no net benefit is gained because performance is merely restored to "baseline" levels. The effects of caffeine in children is an under-researched area, with only a handful of studies being carried out in the US where children's consumption of caffeine appears to be lower on average than in the UK. Twenty-six children aged between 9 and 11 years completed a double-blind, placebo-controlled study. Habitual caffeine consumers (mean daily caffeine intake = 109 mg) and non/low-consumers (12 mg) were tested on two separate days following overnight caffeine abstinence. On each day measures of cognitive performance (a number search task), and self-rated mood and physical symptoms, including alertness and headache, were taken before and after administration of 50 mg of caffeine, or placebo. At baseline (before treatment), the habitual consumers showed poorer performance on the cognitive test than did the non/low-consumers, although no significant differences in mood or physical symptoms were found between the two groups. There were significant habit by treatment (caffeine vs. placebo) interactions for accuracy of performance and headache, and a significant main effect of treatment for alertness. Post hoc comparisons showed that caffeine administration improved the consumers' accuracy on the cognitive test (to near the level displayed by the non/low-consumers at baseline), but that it had no significant effect on the non/low-consumers' performance. In the consumers, caffeine prevented an increase in headache that occurred after placebo, and it increased alertness relative to placebo. Again, however, caffeine did not significantly affect levels of headache or alertness in the non

Effects of acute caffeine supplementation on reducing exercise-associated hypoglycaemia in individuals with Type 1 diabetes mellitus.

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Zaharieva, D P; Miadovnik, L A; Rowan, C P; Gumieniak, R J; Jamnik, V K; Riddell, M C

2016-04-01

To determine the effects of acute caffeine ingestion on glycaemia during moderate to vigorous intensity aerobic exercise and in recovery in individuals with Type 1 diabetes. A total of 13 patients with Type 1 diabetes [eight women, five men: mean ± sd age 25.9 ± 8.8 years, BMI 71.9 ± 11.0 kg, maximal oxygen consumption 46.6 ± 12.7 ml/kg/min, body fat 19.9 ± 7.2%, duration of diabetes 14.4 ± 10.1 years and HbA1c 55 ± 8 mmol/mol (7.4 ± 0.8%)] were recruited. Participants ingested capsules that contained gelatin or pure caffeine (6.0 mg/kg body mass) and performed afternoon exercise for 45 min at 60% maximal oxygen consumption on two separate visits with only circulating basal insulin levels. The main finding was that a single caffeine dose attenuates the drop in glycaemia by 1.8 ± 2.8 mmol/l compared with placebo intake during exercise (P=0.056). Continuous glucose monitoring data, however, showed that caffeine was associated with elevated glycaemia at bedtime after exercise, compared with placebo, but lower glucose concentrations in the early morning the next day. Caffeine intake should be considered as another strategy that may modestly attenuate hypoglycaemia in individuals with Type 1 diabetes during exercise, but should be taken with precautionary measures as it may increase the risk of late-onset hypoglycaemia. © 2015 Diabetes UK.

Genetic polymorphism of the adenosine A2A receptor is associated with habitual caffeine consumption.

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Cornelis, Marilyn C; El-Sohemy, Ahmed; Campos, Hannia

2007-07-01

Caffeine is the most widely consumed stimulant in the world, and individual differences in response to its stimulating effects may explain some of the variability in caffeine consumption within a population. We examined whether genetic variability in caffeine metabolism [cytochrome P450 1A2 (CYP1A2) -163A-->C] or the main target of caffeine action in the nervous system [adenosine A(2A) receptor (ADORA2A) 1083C-->T] is associated with habitual caffeine consumption. Subjects (n=2735) were participants from a study of gene-diet interactions and risk of myocardial infarction who did not have a history of hypertension. Genotype frequencies were examined among persons who were categorized according to their self-reported daily caffeine intake, as assessed with a validated food-frequency questionnaire. The ADORA2A, but not the CYP1A2, genotype was associated with different amounts of caffeine intake. Compared with persons consuming caffeine/d, the odds ratios for having the ADORA2A TT genotype were 0.74 (95% CI: 0.53, 1.03), 0.63 (95% CI: 0.48, 0.83), and 0.57 (95% CI: 0.42, 0.77) for those consuming 100-200, >200-400, and >400 mg caffeine/d, respectively. The association was more pronounced among current smokers than among nonsmokers (P for interaction = 0.07). Persons with the ADORA2A TT genotype also were significantly more likely to consume less caffeine (ie, caffeine consumption increases. This observation provides a biologic basis for caffeine consumption behavior and suggests that persons with this genotype may be less vulnerable to caffeine dependence.

Performance pressure and caffeine both affect cognitive performance, but likely through independent mechanisms

NARCIS (Netherlands)

Boere, J.J.; Fellinger, L.; Huizinga, D.J.H.; Wong, S.F.; Bijleveld, E.H.

2016-01-01

A prevalent combination in daily life, performance pressure and caffeine intake have both been shown to impact people's cognitive performance. Here, we examined the possibility that pressure and caffeine affect cognitive performance via a shared pathway. In an experiment, participants performed a

Role of adenosine receptors in caffeine tolerance

International Nuclear Information System (INIS)

Holtzman, S.G.; Mante, S.; Minneman, K.P.

1991-01-01

Caffeine is a competitive antagonist at adenosine receptors. Receptor up-regulation during chronic drug treatment has been proposed to be the mechanism of tolerance to the behavioral stimulant effects of caffeine. This study reassessed the role of adenosine receptors in caffeine tolerance. Separate groups of rats were given scheduled access to drinking bottles containing plain tap water or a 0.1% solution of caffeine. Daily drug intake averaged 60-75 mg/kg and resulted in complete tolerance to caffeine-induced stimulation of locomotor activity, which could not be surmounted by increasing the dose of caffeine. 5'-N-ethylcarboxamidoadenosine (0.001-1.0 mg/kg) dose dependently decreased the locomotor activity of caffeine-tolerant rats and their water-treated controls but was 8-fold more potent in the latter group. Caffeine (1.0-10 mg/kg) injected concurrently with 5-N-ethylcarboxamidoadenosine antagonized the decreases in locomotor activity comparably in both groups. Apparent pA2 values for tolerant and control rats also were comparable: 5.05 and 5.11. Thus, the adenosine-antagonist activity of caffeine was undiminished in tolerant rats. The effects of chronic caffeine administration on parameters of adenosine receptor binding and function were measured in cerebral cortex. There were no differences between brain tissue from control and caffeine-treated rats in number and affinity of adenosine binding sites or in receptor-mediated increases (A2 adenosine receptor) and decreases (A1 adenosine receptor) in cAMP accumulation. These results are consistent with theoretical arguments that changes in receptor density should not affect the potency of a competitive antagonist. Experimental evidence and theoretical considerations indicate that up-regulation of adenosine receptors is not the mechanism of tolerance to caffeine-induced stimulation of locomotor activity

Role of adenosine receptors in caffeine tolerance

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Holtzman, S.G.; Mante, S.; Minneman, K.P. (Emory Univ. School of Medicine, Atlanta, GA (USA))

1991-01-01

Caffeine is a competitive antagonist at adenosine receptors. Receptor up-regulation during chronic drug treatment has been proposed to be the mechanism of tolerance to the behavioral stimulant effects of caffeine. This study reassessed the role of adenosine receptors in caffeine tolerance. Separate groups of rats were given scheduled access to drinking bottles containing plain tap water or a 0.1% solution of caffeine. Daily drug intake averaged 60-75 mg/kg and resulted in complete tolerance to caffeine-induced stimulation of locomotor activity, which could not be surmounted by increasing the dose of caffeine. 5'-N-ethylcarboxamidoadenosine (0.001-1.0 mg/kg) dose dependently decreased the locomotor activity of caffeine-tolerant rats and their water-treated controls but was 8-fold more potent in the latter group. Caffeine (1.0-10 mg/kg) injected concurrently with 5-N-ethylcarboxamidoadenosine antagonized the decreases in locomotor activity comparably in both groups. Apparent pA2 values for tolerant and control rats also were comparable: 5.05 and 5.11. Thus, the adenosine-antagonist activity of caffeine was undiminished in tolerant rats. The effects of chronic caffeine administration on parameters of adenosine receptor binding and function were measured in cerebral cortex. There were no differences between brain tissue from control and caffeine-treated rats in number and affinity of adenosine binding sites or in receptor-mediated increases (A2 adenosine receptor) and decreases (A1 adenosine receptor) in cAMP accumulation. These results are consistent with theoretical arguments that changes in receptor density should not affect the potency of a competitive antagonist. Experimental evidence and theoretical considerations indicate that up-regulation of adenosine receptors is not the mechanism of tolerance to caffeine-induced stimulation of locomotor activity.

Cortisol responses to mental stress, exercise, and meals following caffeine intake in men and women.

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Lovallo, William R; Farag, Noha H; Vincent, Andrea S; Thomas, Terrie L; Wilson, Michael F

2006-03-01

Caffeine elevates cortisol secretion, and caffeine is often consumed in conjunction with exercise or mental stress. The interactions of caffeine and stress on cortisol secretion have not been explored adequately in women. We measured cortisol levels at eight times on days when healthy men and women consumed caffeine (250 mg x 3) and underwent either mental stress or dynamic exercise protocols, followed by a midday meal, in a double blind, placebo-controlled, crossover design. Men and women had similar cortisol levels at the predrug baselines, but they responded differently to mental stress and exercise. The cortisol response to mental stress was smaller in women than in men (p=.003). Caffeine acted in concert with mental stress to further increase cortisol levels (p=.011), the effect was similar in men and women. Exercise alone did not increase cortisol, but caffeine taken before exercise elevated cortisol in both men and women (psrelease in response to stress and caffeine therefore appears to be a function of the type of stressor and the sex of the subject. However, repeated caffeine doses increased cortisol levels across the test day without regard to the sex of the subject or type of stressor employed (p<.00001). Caffeine may elevate cortisol by stimulating the central nervous system in men but may interact with peripheral metabolic mechanisms in women.

Energy drinks available in Ireland: a description of caffeine and sugar content.

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Keaver, Laura; Gilpin, Susannah; Fernandes da Silva, Joana Caldeira; Buckley, Claire; Foley-Nolan, Cliodhna

2017-06-01

To describe the caffeine and sugar content of all energy drinks available on the island of Ireland. Two retail outlets were selected from each of: multinational, convenience and discount stores in Northern Ireland and the Republic of Ireland, and all available single-serve energy drinks were purchased. The cross-sectional survey was conducted in February 2015 and brand name, price, volume, caffeine and sugar content were recorded for each product. Descriptive analysis was performed. Seventy-eight products were identified on the island of Ireland (regular, n 59; diet/sugar-free/light, n 19). Caffeine and sugar content was in the range of 14-35 mg and 2·9-15·6 g per 100 ml, respectively. Mean caffeine content of 102·2 mg per serving represents 25·6 % of the maximum intake advised for adults by the European Food Safety Authority. Per serving, mean sugar content of regular energy drinks was 37 g. This exceeds WHO recommendations for maximum daily sugar intake of energy intake (25 g for adults consuming 8368 kJ (2000 kcal) diet). If displaying front-of-pack labelling, fifty-seven of the fifty-nine regular energy drinks would receive a Food Standards Agency 'red' colour-coded label for sugar. Energy drinks are freely available on the island of Ireland and all products surveyed can be defined as highly caffeinated products. This has potential health issues particularly for children and adolescents where safe limits of caffeine have not been determined. Energy drinks surveyed also contained high levels of sugar and could potentially contribute to weight gain and adverse dental health effects.

High Blood Caffeine Levels in MCI Linked to Lack of Progression to Dementia

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Cao, Chuanhai; Loewenstein, David A.; Lin, Xiaoyang; Zhang, Chi; Wang, Li; Duara, Ranjan; Wu, Yougui; Giannini, Alessandra; Bai, Ge; Cai, Jianfeng; Greig, Maria; Schofield, Elizabeth; Ashok, Raj; Small, Brent; Potter, Huntington; Arendash, Gary W.

2017-01-01

Although both human epidemiologic and animal model studies have suggested that caffeine/coffee protects against Alzheimer’s disease, direct human evidence for this premise has been lacking. In the present case-control study, two separate cohorts consisting of 124 total individuals (65–88 years old) were cognitively assessed and a blood sample taken for caffeine/biomarker analysis. Subjects were then monitored for cognitive status over the ensuing 2–4 year period to determine the extent to which initial plasma caffeine/biomarkers levels would be predictive of changes in cognitive status. Plasma caffeine levels at study onset were substantially lower (−51%) in mild cognitive impairment (MCI) subjects who later progressed to dementia (MCI→DEM) compared to levels in stable MCI subjects (MCI→MCI). Moreover, none of the MCI→DEM subjects had initial blood caffeine levels that were above a critical level of 1200 ng/ml, while half of stable MCI→MCI subjects had blood caffeine levels higher than that critical level. Thus, plasma caffeine levels greater than 1200 ng/ml (≈6 µM) in MCI subjects were associated with no conversion to dementia during the ensuing 2–4 year follow-up period. Among the 11 cytokines measured in plasma, three of them (GCSF, IL-10, and IL-6) were decreased in MCI→DEM subjects, but not in stable MCI→MCI subjects with high plasma caffeine levels. Coffee would appear to be the major or perhaps only source of caffeine for such stable MCI patients. This case-control study provides the first direct evidence that caffeine/coffee intake is associated with a reduced risk of dementia or delayed onset, particularly for those who already have MCI. PMID:22430531

Combined caffeine and carbohydrate ingestion: effects on nocturnal sleep and exercise performance in athletes.

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Miller, Ben; O'Connor, Helen; Orr, Rhonda; Ruell, Patricia; Cheng, Hoi Lun; Chow, Chin Moi

2014-12-01

In athletes, caffeine use is common although its effects on sleep have not been widely studied. This randomised, double-blind, placebo-controlled crossover trial investigated the effects of late-afternoon caffeine and carbohydrate-electrolyte (CEB) co-ingestion on cycling performance and nocturnal sleep. Six male cyclists/triathletes (age 27.5 ± 6.9 years) completed an afternoon training session (TS; cycling 80 min; 65% VO₂max) followed by a 5 kJ kg(-1) cycling time trial (TT). Caffeine (split dose 2 × 3 mg kg(-1)) or placebo was administered 1 h prior and 40 min into the TS. A 7.4% CEB (3 ml kg(-1) every 15 min) was administered during the TS, followed 30 min after by a standardised evening meal. Participants retired at their usual bedtime and indices of sleep duration and quality were monitored via polysomnography. mean ± SD. All participants performed better in the caffeine TT (caffeine 19.7 ± 3.3; placebo 20.5 ± 3.5 min; p = 0.006), while ratings of perceived exertion (caffeine 12.0 ± 0.6; placebo 12.9 ± 0.7; p = 0.004) and heart rate (caffeine 175 ± 6; placebo 167 ± 11 bpm; p = 0.085) were lower in the caffeine TS. Caffeine intake induced significant disruptions to a number of sleep indices including increased sleep onset latency (caffeine 51.1 ± 34.7; placebo 10.2 ± 4.2 min; p = 0.028) and decreased sleep efficiency (caffeine 76.1 ± 19.6; placebo 91.5 ± 4.2%; p = 0.028), rapid eye movement sleep (caffeine 62.1 ± 19.6; placebo 85.8 ± 24.7 min; p = 0.028) and total sleep time (caffeine 391 ± 97; placebo 464 ± 49 min; p = 0.028). This study supports a performance-enhancing effect of caffeine, although athletes (especially those using caffeine for late-afternoon/evening training and competition) should consider its deleterious effects on sleep.

Wake up and smell the coffee. Caffeine, coffee, and the medical consequences.

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Chou, T

1992-11-01

Caffeine is a methylxanthine whose primary biologic effect is antagonism of the adenosine receptor. Its presence in coffee, tea, soda beverages, chocolate, and many prescription and over-the-counter drugs makes it the most commonly consumed stimulant drug. Initially caffeine increases blood pressure, plasma catecholamine levels, plasma renin activity, serum free fatty acid levels, urine production, and gastric acid secretion. Its long-term effects have been more difficult to substantiate. Most of the caffeine consumed in the United States is in coffee, which contains many other chemicals that may have other biologic actions. The consumption of coffee is a self-reinforcing behavior, and caffeine dependence and addiction are common. Coffee and caffeine intake have been linked to many illnesses, but definitive correlations have been difficult to substantiate. Initial trials showing coffee's association with coronary disease and myocardial infarction have been difficult to reproduce and have many confounding variables. Recent studies showing a larger effect over long follow-up periods and with heavy coffee consumption have again brought the question of the role of coffee in disease states to the fore. Caffeine in average dosages does not seem to increase the risk of arrhythmia. At present there is no convincing evidence that caffeine or coffee consumption increases the risk for any solid tumor. The intake of coffee and caffeine has clearly been decreasing in this country over the past two decades, largely brought about by the increasing health consciousness of Americans. Although there have been many studies that hint that the fears of increased disease with coffee drinking may be warranted, many questions have yet to be answered about the health effects of coffee and caffeine use.

Total and Added Sugar Intake: Assessment in Eight Latin American Countries

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Mauro Fisberg

2018-03-01

Full Text Available Non-communicable diseases are growing at an alarming rate in Latin America. We assessed total and added sugar intake in Argentina, Brazil, Chile, Colombia, Costa Rica, Ecuador, Peru, and Venezuela, to verify the adequacy of the World Health Organization’s recommendations, considering gender, socioeconomic level (SEL and age. A total of 9218 non-institutionalized individuals living in urban areas (age range 15–65 years were assessed in the Latin American Study of Nutrition and Health (ELANS, a multicenter household population-based cross-sectional survey. Socio-demographic data were collected. Total and added sugar intakes were measured using two non-consecutive 24-h dietary recalls. The prevalence of excessive sugar intake was estimated. A large proportion of individuals showed high consumption of total and added sugar intake, which reflected in the high prevalence of excessive sugar intake. With minimal differences across countries, in general, women, individuals with high SEL, and younger people had higher percentages of total energy intake from total and added sugar intake, and of contribution of carbohydrates from total and added sugars. Thus, there is high consumption of total and added sugar intake in the Latin American countries with some peculiarities considering socio-demographic variables, which should be considered in each country’s health intervention proposals.

Chronic ingestion of a low dose of caffeine induces tolerance to the performance benefits of caffeine.

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Beaumont, Ross; Cordery, Philip; Funnell, Mark; Mears, Stephen; James, Lewis; Watson, Phillip

2017-10-01

This study examined effects of 4 weeks of caffeine supplementation on endurance performance. Eighteen low-habitual caffeine consumers (caffeine (1.5-3.0 mg · kg -1 day -1 ; titrated) or placebo for 28 days. Groups were matched for age, body mass, V̇O 2peak and W max (P > 0.05). Before supplementation, all participants completed one V̇O 2peak test, one practice trial and 2 experimental trials (acute 3 mg · kg -1 caffeine [precaf] and placebo [testpla]). During the supplementation period a second V̇O 2peak test was completed on day 21 before a final, acute 3 mg · kg -1 caffeine trial (postcaf) on day 29. Trials consisted of 60 min cycle exercise at 60% V̇O 2peak followed by a 30 min performance task. All participants produced more external work during the precaf trial than testpla, with increases in the caffeine (383.3 ± 75 kJ vs. 344.9 ± 80.3 kJ; Cohen's d effect size [ES] = 0.49; P = 0.001) and placebo (354.5 ± 55.2 kJ vs. 333.1 ± 56.4 kJ; ES = 0.38; P = 0.004) supplementation group, respectively. This performance benefit was no longer apparent after 4 weeks of caffeine supplementation (precaf: 383.3 ± 75.0 kJ vs. postcaf: 358.0 ± 89.8 kJ; ES = 0.31; P = 0.025), but was retained in the placebo group (precaf: 354.5 ± 55.2 kJ vs. postcaf: 351.8 ± 49.4 kJ; ES = 0.05; P > 0.05). Circulating caffeine, hormonal concentrations and substrate oxidation did not differ between groups (all P > 0.05). Chronic ingestion of a low dose of caffeine develops tolerance in low-caffeine consumers. Therefore, individuals with low-habitual intakes should refrain from chronic caffeine supplementation to maximise performance benefits from acute caffeine ingestion.

Caffeine Concentrations in Coffee, Tea, Chocolate, and Energy Drink Flavored E-liquids.

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Lisko, Joseph G; Lee, Grace E; Kimbrell, J Brett; Rybak, Michael E; Valentin-Blasini, Liza; Watson, Clifford H

2017-04-01

compliance for those geographic regions that forbid caffeine in e-cigarette products. The application of the method shows that caffeine concentrations and estimated total caffeine exposure from e-cigarette products is significantly lower than oral intake from beverages. However, because very little is known about the effects of caffeine inhalation, e-cigarette users should proceed with caution when using caffeine containing e-cigarette products. Further research is necessary to determine associated effects from inhaling caffeine. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Caffeine and 3-km cycling performance: Effects of mouth rinsing, genotype, and time of day.

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Pataky, M W; Womack, C J; Saunders, M J; Goffe, J L; D'Lugos, A C; El-Sohemy, A; Luden, N D

2016-06-01

We assessed the efficacy of caffeine mouth rinsing on 3-km cycling performance and determined whether caffeine mouth rinsing affects performance gains influenced by the CYP1A2 polymorphism. Thirty-eight recreational cyclists completed four simulated 3-km time trials (TT). Subjects ingested either 6 mg/kg BW of caffeine or placebo 1 h prior to each TT. Additionally, 25 mL of 1.14% caffeine or placebo solution were mouth rinsed before each TT. The treatments were Placebo, caffeine Ingestion, caffeine Rinse and Ingestion+Rinse. Subjects were genotyped and classified as AA homozygotes or AC heterozygotes for the rs762551 polymorphism of the CYP1A2 gene involved in caffeine metabolism. Magnitude-based inferences were used to evaluate treatment differences in mean power output based on a predetermined meaningful treatment effect of 1.0%. AC heterozygotes (4.1%) and AA homozygotes (3.4%) benefited from Ingestion+Rinse, but only AC performed better with Ingestion (6.0%). Additionally, Rinse and Ingestion+Rinse elicited better performance relative to Placebo among subjects that performed prior to 10:00 h (Early) compared with after 10:00 h (Late). The present study provides additional evidence of genotype and time of day factors that affect the ergogenic value of caffeine intake that may allow for more personalized caffeine intake strategies to maximize performance. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Caffeine-containing energy drink improves physical performance of elite rugby players during a simulated match.

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Del Coso, Juan; Ramírez, Juan A; Muñoz, Gloria; Portillo, Javier; Gonzalez-Millán, Cristina; Muñoz, Víctor; Barbero-Álvarez, José C; Muñoz-Guerra, Jesús

2013-04-01

The purpose of this study was to investigate the effectiveness of a caffeine-containing energy drink in enhancing rugby players' physical performance during a simulated match. A second purpose was to determine the urinary caffeine excretion derived from the energy drink intake. In a randomized and counterbalanced order, 26 elite rugby players (mean ± SD for age and body mass, 25 ± 2 y and 93 ± 15 kg) played 2 simulated rugby games (2 × 30 min) 60 min after ingesting (i) 3 mg of caffeine per kilogram of body mass in the form of an energy drink (Fure, ProEnergetics) or (ii) the same drink without caffeine (placebo). During the matches, the individual running distance and the instantaneous speed were measured, and the number of running actions above 20 km·h(-1) (i.e., sprints) were determined, using global positioning system devices. The number of impacts above 5 g during the matches was determined by accelerometry. The ingestion of the energy drink, compared with the placebo, increased the total distance covered during the match (4749 ± 589 vs 5139 ± 475 m, p caffeine concentration (0.1 ± 0.1 vs 2.4 ± 0.9 μg·mL(-1), p caffeine dose equivalent to 3 mg·kg(-1) considerably enhanced the movement patterns of rugby players during a simulated match.

Teratogenic effects of caffeine and clomipramine on rat fetus

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Takzare N

2012-09-01

Full Text Available Background: Obsessive-compulsive disorders and depression have a high prevalence during pregnancy therefore, pregnant women may take clomipramine and also take other drugs or consume foods that contain caffeine. As investigations about the teratogenic effects of clomipramine and its concurrent administration with caffeine during organogenesis period are scarce, we aimed to study the teratogenicity of simultaneous administration of clomipramine and caffeine in rat fetus.Methods: After dividing 42 pregnant rats to several case and control groups, we injected different doses of caffeine and clomipramine to the animals. All the injections were performed on the eighth until the 15th day of pregnancy. We removed the fetuses on the 17th day of pregnancy and studied the morphological features and apparent anomalies of the fetuses macroscopically. Results: We found a significant rate of mortality, apparent anomalies, abnormal torsion, shrinkage of skin and subcutaneous bleeding in fetuses of rats receiving high doses of caffeine or a combination of caffeine and clomipramine. Statistical analysis of the data revealed a significant increase (P?0.001 in teratogenicity of high doses of caffeine and its combination with clomipramine. Conclusion: This study implies simultaneous intake of high amounts of caffeine and clomipramine lead to teratogenicity. We recommend pregnant women to avoid uncontrolled consumption of foods that contain caffeine or drugs that contain high amounts of this substance. They should not also take clomipramine with caffeine in the first trimester of pregnancy.

Associations of Urinary Caffeine and Caffeine Metabolites With Arterial Stiffness in a Large Population-Based Study.

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Ponte, Belen; Pruijm, Menno; Ackermann, Daniel; Ehret, Georg; Ansermot, Nicolas; Staessen, Jan A; Vogt, Bruno; Pechère-Bertschi, Antoinette; Burnier, Michel; Martin, Pierre-Yves; Eap, Chin B; Bochud, Murielle; Guessous, Idris

2018-05-01

To assess the influence of caffeine on arterial stiffness by exploring the association of urinary excretion of caffeine and its related metabolites with pulse pressure (PP) and pulse wave velocity (PWV). Families were randomly selected from the general population of 3 Swiss cities from November 25, 2009, through April 4, 2013. Pulse pressure was defined as the difference between the systolic and diastolic blood pressures obtained by 24-hour ambulatory monitoring. Carotid-femoral PWV was determined by applanation tonometry. Urinary caffeine, paraxanthine, theophylline, and theobromine excretions were measured in 24-hour urine collections. Multivariate linear and logistic mixed models were used to explore the associations of quartiles of urinary caffeine and metabolite excretions with PP, high PP, and PWV. We included 863 participants with a mean ± SD age of 47.1±17.6 years, 24-hour PP of 41.9±9.2 mm Hg, and PWV of 8.0±2.3 m/s. Mean (SE) brachial PP decreased from 43.5 (0.5) to 40.5 (0.6) mm Hg from the lowest to the highest quartiles of 24-hour urinary caffeine excretion (P<.001). The odds ratio (95% CI) of high PP decreased linearly from 1.0 to 0.52 (0.31-0.89), 0.38 (0.22-0.65), and 0.31 (0.18-0.55) from the lowest to the highest quartile of 24-hour urinary caffeine excretion (P<.001). Mean (SE) PWV in the highest caffeine excretion quartile was significantly lower than in the lowest quartile (7.8 [0.1] vs 8.1 [0.1] m/s; P=.03). Similar associations were found for paraxanthine and theophylline, whereas no associations were found with theobromine. Urinary caffeine, paraxanthine, and theophylline excretions were associated with decreased parameters of arterial stiffness, suggesting a protective effect of caffeine intake beyond its blood pressure-lowering effect. Copyright © 2017 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

Caffeine Inhibits Fluid Secretion by Interlobular Ducts From Guinea Pig Pancreas.

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Mochimaru, Yuka; Yamamoto, Akiko; Nakakuki, Miyuki; Yamaguchi, Makoto; Taniguchi, Ituka; Ishiguro, Hiroshi

2017-04-01

Caffeine is contained in coffee, tea, and numerous beverages and foods. We examined the direct effects of caffeine on the physiological function of pancreatic duct cells by using interlobular duct segments isolated from guinea pig pancreas. The rate of fluid secretion was continuously measured by monitoring the luminal volume of isolated duct segments. Changes in intracellular Ca concentration ([Ca]i) were estimated by microfluorometry in ducts loaded with Fura-2. Both secretin-stimulated and acetylcholine (ACh)-stimulated fluid secretions were substantially and reversibly inhibited by relatively low concentrations of caffeine as low as 0.03 mM relevant to blood levels after ingestion of caffeine-containing beverages. Caffeine inhibited ACh-induced elevation of [Ca]i and secretin-induced fluctuation of [Ca]i. Caffeine abolished thapsigargin-induced intracellular Ca release but did not affect the entry of extracellular Ca. Caffeine (0.05 mM) abolished ethanol (1 mM)-induced fluid hypersecretion in secretin-stimulated pancreatic duct. Low concentrations of caffeine directly inhibit pancreatic ductal fluid secretion stimulated by secretin or ACh and also ethanol-induced fluid hypersecretion. The inhibition by caffeine seems to be mediated by the blockade of intracellular Ca mobilization. Daily intake of caffeine may reduce the volume of pancreatic juice secretion.

Ergogenic effects of caffeine and sodium bicarbonate supplementation on intermittent exercise performance preceded by intense arm cranking exercise

DEFF Research Database (Denmark)

Marriott, Matthaus; Krustrup, Peter; Mohr, Magni

2015-01-01

BACKGROUND: Caffeine and sodium bicarbonate ingestion have been suggested to improve high-intensity intermittent exercise, but it is unclear if these ergogenic substances affect performance under provoked metabolic acidification. To study the effects of caffeine and sodium bicarbonate on intense...... to CAF and PLA, while no difference in heart rate was observed between trials. CONCLUSIONS: Caffeine and sodium bicarbonate administration improved Yo-Yo IR2 performance and lowered perceived exertion after intense arm cranking exercise, with greater overall effects of sodium bicarbonate intake....... intermittent exercise performance and metabolic markers under exercise-induced acidification, intense arm-cranking exercise was performed prior to intense intermittent running after intake of placebo, caffeine and sodium bicarbonate. METHODS: Male team-sports athletes (n = 12) ingested sodium bicarbonate (Na...

Alcohol, cannabis, nicotine, and caffeine use and symptom distress in schizophrenia.

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Hamera, E; Schneider, J K; Deviney, S

1995-09-01

The high prevalence of substance use, e.g., alcohol and illegal and nonprescribed drugs, in schizophrenia is widely recognized. One explanation for this high prevalence is that substance use may be a self-initiated method for managing symptoms. To test whether the intake of four substances--alcohol, cannabis, nicotine, and caffeine--would increase with increases in symptom distress, daily self-reports of symptom distress and substance intake over 12 weeks were analyzed with pooled time series analyses. Compliance with neuroleptic medication was added to the analyses to control for any changes in prescribed medication compliance while using nonprescribed drugs or alcohol. Of the four substances studied, only nicotine was significantly related to symptom distress. Higher distress with prodromal symptoms was related to decreases in nicotine use. Analysis of caffeine did not meet the criteria for significance but does provide direction for further research. Higher distress, with neurotic symptoms, was related to increases in caffeine use. Further research is needed to clarify the relationship between nicotine and symptoms.

Recommendations regarding dietary intake and caffeine and alcohol consumption in patients with cardiac arrhythmias: what do you tell your patients to do or not to do?

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Glatter, Kathryn A; Myers, Richard; Chiamvimonvat, Nipavan

2012-10-01

The etiology of arrhythmias including atrial fibrillation is multifactorial. Most arrhythmias are associated with comorbid illnesses like hypertension, diabetes, thyroid disease, or advanced age. Although it is tempting to blame a stimulant like caffeine as a trigger for arrhythmias, the literature does not support this idea. There is no real benefit to having patients with arrhythmias limit their caffeine intake. Caffeine is a vasoactive substance that also may promote the release of norepinephrine and epinephrine. However, acute ingestion of caffeine (as coffee or tea) does not cause atrial fibrillation. Even patients suffering a myocardial infarction do not have an increased incidence of ventricular or other arrhythmias after ingesting several cups of coffee. Large epidemiologic studies have also failed to find a connection between the amount of coffee/caffeine used and the development of arrhythmias. As such, it does not make sense to suggest that patients with palpitations, paroxysmal atrial fibrillation, or supraventricular tachycardia, abstain from caffeine use. Energy drinks are a new phenomenon on the beverage market, with 30-50 % of young adults and teens using them regularly. Energy drinks are loaded with caffeine, sugar, and other chemicals that can stimulate the cardiac system. There is an increasing body of mainly anecdotal case reports describing arrhythmias or even sudden death triggered by exercise plus using energy drinks. Clearly, there must be more study in this area, but it is wise to either limit or avoid their use in patients with arrhythmias. Moderate to heavy alcohol use seems to be associated with the development of atrial fibrillation. The term "holiday heart" was coined back in 1978, to describe patients who had atrial fibrillation following binge alcohol use. Thus, it is reasonable to recommend to patients with arrhythmias that they limit their alcohol use, although unfortunately this treatment will likely not completely resolve their

Caffeine Improves Basketball Performance in Experienced Basketball Players

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Puente, Carlos; Areces, Francisco

2017-01-01

The aim of this study was to determine the effect of caffeine intake on overall basketball performance in experienced players. A double-blind, placebo-controlled, randomized experimental design was used for this investigation. In two different sessions separated by one week, 20 experienced basketball players ingested 3 mg of caffeine/kg of body mass or a placebo. After 60 min, participants performed 10 repetitions of the following sequence: Abalakov jump, Change-of-Direction and Acceleration Test (CODAT) and two free throws. Later, heart rate, body impacts and game statistics were recorded during a 20-min simulated basketball game. In comparison to the placebo, the ingestion of caffeine increased mean jump height (37.3 ± 6.8 vs. 38.2 ± 7.4 cm; p = 0.012), but did not change mean time in the CODAT test or accuracy in free throws. During the simulated game, caffeine increased the number of body impacts (396 ± 43 vs. 410 ± 41 impacts/min; p basketball players. PMID:28925969

Effects of caffeine on fractional flow reserve values measured using intravenous adenosine triphosphate.

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Nakayama, Masafumi; Chikamori, Taishiro; Uchiyama, Takashi; Kimura, Yo; Hijikata, Nobuhiro; Ito, Ryosuke; Yuhara, Mikio; Sato, Hideaki; Kobori, Yuichi; Yamashina, Akira

2018-04-01

We investigated the effects of caffeine intake on fractional flow reserve (FFR) values measured using intravenous adenosine triphosphate (ATP) before cardiac catheterization. Caffeine is a competitive antagonist for adenosine receptors; however, it is unclear whether this antagonism affects FFR values. Patients were evenly randomized into 2 groups preceding the FFR study. In the caffeine group (n = 15), participants were given coffee containing 222 mg of caffeine 2 h before the catheterization. In the non-caffeine group (n = 15), participants were instructed not to take any caffeine-containing drinks or foods for at least 12 h before the catheterization. FFR was performed in patients with more than intermediate coronary stenosis using the intravenous infusion of ATP at 140 μg/kg/min (normal dose) and 170 μg/kg/min (high dose), and the intracoronary infusion of papaverine. FFR was followed for 30 s after maximal hyperemia. In the non-caffeine group, the FFR values measured with ATP infusion were not significantly different from those measured with papaverine infusion. However, in the caffeine group, the FFR values were significantly higher after ATP infusion than after papaverine infusion (P = 0.002 and P = 0.007, at normal and high dose ATP vs. papaverine, respectively). FFR values with ATP infusion were significantly increased 30 s after maximal hyperemia (P = 0.001 and P < 0.001 for normal and high dose ATP, respectively). The stability of the FFR values using papaverine showed no significant difference between the 2 groups. Caffeine intake before the FFR study affected FFR values and their stability. These effects could not be reversed by an increased ATP dose.

Total Water Intake from Beverages and Foods Is Associated with Energy Intake and Eating Behaviors in Korean Adults

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Lee, Kyung Won; Shin, Dayeon; Song, Won O.

2016-01-01

Water is essential for the proper functioning of the body. Even though a recommendation exists for adequate water intake for Koreans, studies identifying actual water intake from all beverages and foods consumed daily in the Korean population are limited. Thus, we estimated total water intake from both beverages and foods and its association with energy intake and eating behaviors in Korean adults. We used a nationally representative sample of 25,122 Korean adults aged ≥19 years, from the Korean National Health and Nutrition Examination Survey 2008–2012. We performed multiple regression analyses, adjusting for sociodemographic and health-related variables to investigate the contribution of overall energy and dietary intakes and eating behaviors to total water intake. The mean total water intake excluding plain water was 1071 g (398 g from beverages and 673 g from foods) and the estimated plain water intake was 1.3 L. Among Korean adults, 82% consumed beverages (excluding plain water) and these beverages contributed to 10% of daily energy intake and 32% of total water intake from beverages and foods. For every 100 kcal/day in energy intake, water intake consumed through beverages and foods increased by 18 g and 31 g, respectively. Water intake from beverages and foods was positively associated with energy from fat and dietary calcium, but inversely associated with energy density and energy from carbohydrates. When there was a 5% increase in energy intake from snacks and eating outside the home, there was an increase in water intake from beverages of 13 g and 2 g, respectively. Increased daily energy intake, the number of eating episodes, and energy intake from snacks and eating outside the home predicted higher water intake from beverages and foods. Our results provide evidence suggesting that various factors, including sociodemographic status, dietary intakes, and eating behaviors, could be important contributors to the water intake of Korean adults. Findings

Total Water Intake from Beverages and Foods Is Associated with Energy Intake and Eating Behaviors in Korean Adults

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Kyung Won Lee

2016-10-01

Full Text Available Water is essential for the proper functioning of the body. Even though a recommendation exists for adequate water intake for Koreans, studies identifying actual water intake from all beverages and foods consumed daily in the Korean population are limited. Thus, we estimated total water intake from both beverages and foods and its association with energy intake and eating behaviors in Korean adults. We used a nationally representative sample of 25,122 Korean adults aged ≥19 years, from the Korean National Health and Nutrition Examination Survey 2008–2012. We performed multiple regression analyses, adjusting for sociodemographic and health-related variables to investigate the contribution of overall energy and dietary intakes and eating behaviors to total water intake. The mean total water intake excluding plain water was 1071 g (398 g from beverages and 673 g from foods and the estimated plain water intake was 1.3 L. Among Korean adults, 82% consumed beverages (excluding plain water and these beverages contributed to 10% of daily energy intake and 32% of total water intake from beverages and foods. For every 100 kcal/day in energy intake, water intake consumed through beverages and foods increased by 18 g and 31 g, respectively. Water intake from beverages and foods was positively associated with energy from fat and dietary calcium, but inversely associated with energy density and energy from carbohydrates. When there was a 5% increase in energy intake from snacks and eating outside the home, there was an increase in water intake from beverages of 13 g and 2 g, respectively. Increased daily energy intake, the number of eating episodes, and energy intake from snacks and eating outside the home predicted higher water intake from beverages and foods. Our results provide evidence suggesting that various factors, including sociodemographic status, dietary intakes, and eating behaviors, could be important contributors to the water intake of Korean

Total Water Intake from Beverages and Foods Is Associated with Energy Intake and Eating Behaviors in Korean Adults.

Science.gov (United States)

Lee, Kyung Won; Shin, Dayeon; Song, Won O

2016-10-04

Water is essential for the proper functioning of the body. Even though a recommendation exists for adequate water intake for Koreans, studies identifying actual water intake from all beverages and foods consumed daily in the Korean population are limited. Thus, we estimated total water intake from both beverages and foods and its association with energy intake and eating behaviors in Korean adults. We used a nationally representative sample of 25,122 Korean adults aged ≥19 years, from the Korean National Health and Nutrition Examination Survey 2008-2012. We performed multiple regression analyses, adjusting for sociodemographic and health-related variables to investigate the contribution of overall energy and dietary intakes and eating behaviors to total water intake. The mean total water intake excluding plain water was 1071 g (398 g from beverages and 673 g from foods) and the estimated plain water intake was 1.3 L. Among Korean adults, 82% consumed beverages (excluding plain water) and these beverages contributed to 10% of daily energy intake and 32% of total water intake from beverages and foods. For every 100 kcal/day in energy intake, water intake consumed through beverages and foods increased by 18 g and 31 g, respectively. Water intake from beverages and foods was positively associated with energy from fat and dietary calcium, but inversely associated with energy density and energy from carbohydrates. When there was a 5% increase in energy intake from snacks and eating outside the home, there was an increase in water intake from beverages of 13 g and 2 g, respectively. Increased daily energy intake, the number of eating episodes, and energy intake from snacks and eating outside the home predicted higher water intake from beverages and foods. Our results provide evidence suggesting that various factors, including sociodemographic status, dietary intakes, and eating behaviors, could be important contributors to the water intake of Korean adults. Findings

Milk intake in kits: not only the total amount matters

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Alberto Arnau Bonachera

2017-06-01

Full Text Available The aim of this work was to identify milk intake variation patterns in kits throughout lactation, to evaluate their permanent maternal component and their relationships with the performance of kits before and after weaning. To achieve this goal, we used 73 rabbit does, controlled between the 1st and the 4th lactation, which kindled 229 litters with a total of 2225 kits. The daily milk intake records per young rabbit were analysed using a principal component analysis (PCA. We found that 72.3% of the variability was explained by the first 3 principal components (PCs. PC1 explained 46.4% of the total variability, was associated with the total amount of milk intake during lactation and presented a repeatability of 0.27 (P0.05. This component was little related to performance traits. Therefore, it seems that milk plays 2 different roles at the beginning of feed intake; the most important would affect development of the kits and thus is related with high intake. The second one, for a given total amount of milk intake during lactation, would create a kind of competition between milk and feed intake at the end of lactation. The effects of both components still persist during the growing period and seem to be moderately affected by the mother.

Caffeine improves left hemisphere processing of positive words.

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Kuchinke, Lars; Lux, Vanessa

2012-01-01

A positivity advantage is known in emotional word recognition in that positive words are consistently processed faster and with fewer errors compared to emotionally neutral words. A similar advantage is not evident for negative words. Results of divided visual field studies, where stimuli are presented in either the left or right visual field and are initially processed by the contra-lateral brain hemisphere, point to a specificity of the language-dominant left hemisphere. The present study examined this effect by showing that the intake of caffeine further enhanced the recognition performance of positive, but not negative or neutral stimuli compared to a placebo control group. Because this effect was only present in the right visual field/left hemisphere condition, and based on the close link between caffeine intake and dopaminergic transmission, this result points to a dopaminergic explanation of the positivity advantage in emotional word recognition.

Caffeine improves left hemisphere processing of positive words.

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Lars Kuchinke

Full Text Available A positivity advantage is known in emotional word recognition in that positive words are consistently processed faster and with fewer errors compared to emotionally neutral words. A similar advantage is not evident for negative words. Results of divided visual field studies, where stimuli are presented in either the left or right visual field and are initially processed by the contra-lateral brain hemisphere, point to a specificity of the language-dominant left hemisphere. The present study examined this effect by showing that the intake of caffeine further enhanced the recognition performance of positive, but not negative or neutral stimuli compared to a placebo control group. Because this effect was only present in the right visual field/left hemisphere condition, and based on the close link between caffeine intake and dopaminergic transmission, this result points to a dopaminergic explanation of the positivity advantage in emotional word recognition.

Chronic prenatal caffeine exposure impairs novel object recognition and radial arm maze behaviors in adult rats.

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Soellner, Deborah E; Grandys, Theresa; Nuñez, Joseph L

2009-12-14

In this report, we demonstrate that chronic prenatal exposure to a moderate dose of caffeine disrupts novel object recognition and radial arm maze behaviors in adult male and female rats. Pregnant dams were administered either tap water or 75 mg/L caffeinated tap water throughout gestation. Oral self-administration in the drinking water led to an approximate maternal intake of 10mg/kg/day, equivalent to 2-3 cups of coffee/day in humans based on a metabolic body weight conversion. In adulthood, the offspring underwent testing on novel object recognition, radial arm maze, and Morris water maze tasks. Prenatal caffeine exposure was found to impair 24-h memory retention in the novel object recognition task and impair both working and reference memory in the radial arm maze. However, prenatal caffeine exposure did not alter Morris water maze performance in either a simple water maze procedure or in an advanced water maze procedure that included reversal and working memory paradigms. These findings demonstrate that chronic oral intake of caffeine throughout gestation can alter adult cognitive behaviors in rats.

Prenatal Caffeine Exposure Impairs Pregnancy in Rats

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Maryam Yadegari

2016-12-01

Full Text Available Background: In recent years, concerns have been raised about human reproductive disorders. Caffeine consumption is increasing by the world’s population and there is a relationship between caffeine intake and adverse reproductive outcomes. The aim of this study was to evaluate the effects of caffeine on implantation sites, number of live births, birth weight, crown-rump length (CRL and abnormality in pregnant rats. Materials and Methods: In this experimental study, 40 female albino rats (170-190 g were randomly divided into two experimental and two control groups (n=10/each group. In both experimental groups, animals received caffeine intraperitoneally (IP: 150 mg/kg/day on days 1-5 of pregnancy. In experimental group 1, treated animals were euthanized on day 7of pregnancy and the number of implantation sites was counted. In experimental group 2, treated animals maintained pregnant and after delivery, the number of live births, birth weight, CRL and abnormality of neonates were investigated. In control group, animals received IP injections of distilled water. Data were analyzed by independent t test. Results: Results showed that administration of caffeine significantly decreased the number of implantation sites, number of live births and CRL as compared with control group (P<0.05. There were no significant differences regarding birth weight and abnormality of neonate rats between experimental and control groups. Conclusion: These results suggest that caffeine caused anti-fertility effect and significantly decreased CRL in neonate rats.

Caffeine-containing energy drink improves physical performance in female soccer players.

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Lara, Beatriz; Gonzalez-Millán, Cristina; Salinero, Juan Jose; Abian-Vicen, Javier; Areces, Francisco; Barbero-Alvarez, Jose Carlos; Muñoz, Víctor; Portillo, Luis Javier; Gonzalez-Rave, Jose Maria; Del Coso, Juan

2014-05-01

There is little information about the effects of caffeine intake on female team-sport performance. The aim of this study was to investigate the effectiveness of a caffeine-containing energy drink to improve physical performance in female soccer players during a simulated game. A double-blind, placebo controlled and randomized experimental design was used in this investigation. In two different sessions, 18 women soccer players ingested 3 mg of caffeine/kg in the form of an energy drink or an identical drink with no caffeine content (placebo). After 60 min, they performed a countermovement jump (CMJ) and a 7 × 30 m sprint test followed by a simulated soccer match (2 × 40 min). Individual running distance and speed were measured using GPS devices. In comparison to the placebo drink, the ingestion of the caffeinated energy drink increased the CMJ height (26.6 ± 4.0 vs 27.4 ± 3.8 cm; P 18 km/h (161 ± 99 vs 216 ± 103 m; P caffeine/kg might be an effective ergogenic aid to improve physical performance in female soccer players.

Dose-Dependent Model of Caffeine Effects on Human Vigilance during Total Sleep Deprivation

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2014-05-20

does not consider the absorption of caffeine. This is a reasonable approximation for caffeine when ingested via coffee , tea, energy drinks, and most...administered in chewing gum versus capsules to normal healthy volunteers. Int. J. Pharm. 234 (1-2), 159–167 (http://dx.doi.org/S0378517301009589). Kamimori

Administration of Caffeine in Alternate Forms.

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Wickham, Kate A; Spriet, Lawrence L

2018-03-01

There has been recent interest in the ergogenic effects of caffeine delivered in low doses (~ 200 mg or ~ 3 mg/kg body mass) and administered in forms other than capsules, coffee and sports drinks, including chewing gum, bars, gels, mouth rinses, energy drinks and aerosols. Caffeinated chewing gum is absorbed quicker through the buccal mucosa compared with capsule delivery and absorption in the gut, although total caffeine absorption over time is not different. Rapid absorption may be important in many sporting situations. Caffeinated chewing gum improved endurance cycling performance, and there is limited evidence that repeated sprint cycling and power production may also be improved. Mouth rinsing with caffeine may stimulate nerves with direct links to the brain, in addition to caffeine absorption in the mouth. However, caffeine mouth rinsing has not been shown to have significant effects on cognitive performance. Delivering caffeine with mouth rinsing improved short-duration, high-intensity, repeated sprinting in normal and depleted glycogen states, while the majority of the literature indicates no ergogenic effect on aerobic exercise performance, and resistance exercise has not been adequately studied. Studies with caffeinated energy drinks have generally not examined the individual effects of caffeine on performance, making conclusions about this form of caffeine delivery impossible. Caffeinated aerosol mouth and nasal sprays may stimulate nerves with direct brain connections and enter the blood via mucosal and pulmonary absorption, although little support exists for caffeine delivered in this manner. Overall, more research is needed examining alternate forms of caffeine delivery including direct measures of brain activation and entry of caffeine into the blood, as well as more studies examining trained athletes and female subjects.

Effects of coffee and caffeine anhydrous on strength and sprint performance.

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Trexler, Eric T; Smith-Ryan, Abbie E; Roelofs, Erica J; Hirsch, Katie R; Mock, Meredith G

2016-09-01

Caffeine and coffee are widely used among active individuals to enhance performance. The purpose of the current study was to compare the effects of acute coffee (COF) and caffeine anhydrous (CAF) intake on strength and sprint performance. Fifty-four resistance-trained males completed strength testing, consisting of one-rep max (1RM) and repetitions to fatigue (RTF) at 80% of 1RM for leg press (LP) and bench press (BP). Participants then completed five, 10-second cycle ergometer sprints separated by one minute of rest. Peak power (PP) and total work (TW) were recorded for each sprint. At least 48 hours later, participants returned and ingested a beverage containing CAF (300 mg flat dose; yielding 3-5 mg/kg bodyweight), COF (8.9 g; 303 mg caffeine), or placebo (PLA; 3.8 g non-caloric flavouring) 30 minutes before testing. LP 1RM was improved more by COF than CAF (p = .04), but not PLA (p = .99). Significant interactions were not observed for BP 1RM, BP RTF, or LP RTF (p > .05). There were no sprint × treatment interactions for PP or TW (p > .05). 95% confidence intervals revealed a significant improvement in sprint 1 TW for CAF, but not COF or PLA. For PLA, significant reductions were observed in sprint 4 PP, sprint 2 TW, sprint 4 TW, and average TW; significant reductions were not observed with CAF or COF. Neither COF nor CAF improved strength outcomes more than PLA, while both groups attenuated sprint power reductions to a similar degree. Coffee and caffeine anhydrous may be considered suitable pre-exercise caffeine sources for high-intensity exercise.

Beverage Consumption Habits in Italian Population: Association with Total Water Intake and Energy Intake

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Lorenza Mistura

2016-10-01

Full Text Available Background: The aim of this study was to investigate total water intake (TWI from water, beverages and foods among Italian adults and the elderly. Methods: Data of 2607 adults and the elderly, aged 18–75 years from the last national food consumption survey, INRAN-SCAI 2005-06, were used to evaluate the TWI. The INRAN-SCAI 2005-06 survey was conducted on a representative sample of 3323 individuals aged 0.1 to 97.7 years. A 3-day semi-structured diary was used for participants to record the consumption of all foods, beverages and nutritional supplements. Results: On average, TWI was 1.8 L for men and 1.7 L for women. More than 75% of women and 90% of men did not comply with the European Food Safety Authority (EFSA Adequate Intake. The contribution of beverages to the total energy intake (EI was 6% for the total sample. Water was the most consumed beverage, followed by alcoholic beverages for men and hot beverages for women. Conclusion: According to the present results, adults and elderly Italians do not reach the adequate intake for water as suggested by the EFSA and by the national reference level of nutrient and energy intake. Data on water consumption should also be analyzed in single socio-demographic groups in order to identify sub-groups of the population that need more attention and to plan more targeted interventions.

Caffeine as a model drug of dependence: recent developments in understanding caffeine withdrawal, the caffeine dependence syndrome, and caffeine negative reinforcement.

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Griffiths, R R; Chausmer, A L

2000-11-01

Caffeine is an excellent model compound for understanding drugs of abuse/dependence. The results of self-administration and choice studies in humans clearly demonstrate the reinforcing effects of low and moderate doses of caffeine. Caffeine reinforcement has been demonstrated in about 45% of normal subjects with histories of moderate and heavy caffeine use. Recent studies provide compelling evidence that caffeine physical dependence potentiates the reinforcing effects of caffeine through the mechanism of withdrawal symptom avoidance. Tolerance to the subjective and sleep-disrupting effects of caffeine in humans has been demonstrated. Physical dependence as reflected in a withdrawal syndrome in humans has been repeatedly demonstrated in adults and recently demonstrated in children. Withdrawal severity is an increasing function of caffeine maintenance dose, with withdrawal occurring at doses as low as 100 mg per day. Increased cerebral blood flow may be the physiological mechanism for caffeine withdrawal headache. Case studies in adults and adolescents clearly demonstrate that some individuals meet DSM-IV diagnostic criteria for a substance dependence syndrome on caffeine, including feeling compelled to continue caffeine use despite desires and recommendations to the contrary. Survey data suggest that 9% to 30% percent of caffeine consumers may be caffeine dependent according to DSM-IV criteria.

Total dietary intake of mercury in the Canary Islands, Spain.

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Rubio, C; Gutiérrez, A; Burgos, A; Hardisson, A

2008-08-01

Estimating the risk associated with dietary intake of heavy metals by consumers is a vital and integral part of regulatory processes. The assessment of exposure to mercury shown in this paper has been performed by means of a study on the whole diet. Total mercury (Hg) levels were determined by cold vapour atomic absorption spectrometry (AAS) in 420 samples of regularly consumed food and drink. The total Hg concentrations measured in the different groups of food ranged from non-detectable to 119 microg kg(-1) w/w. The fish group had the highest concentrations of total Hg. All groups of food with regulated Hg content showed levels that were lower than the legally set values. The food consumption data used in the analysis were taken from the latest nutritional survey made in the Canary Islands, Spain. The estimated total Hg intake of local population (5.7 microg/person day(-1)) did not exceed the provisional tolerable weekly intake (PTWI) limit of 0.3 mg week(-1) of total mercury (43 microg/person day(-1)) fixed by the Joint Food and Agricultural Organization/World Health Organization (FAO/WHO) Expert Committee on Food Additives. Fishery products contributed 96% of the total Hg intake. The mean Hg intake for each island in this archipelago, formed by seven, has also been calculated. Fuerteventura, Lanzarote and El Hierro are the islands with the highest level of Hg intake (7.0, 7,0 and 6.1 microg/person day(-1), respectively). La Palma Island, due to its low fish consumption, had the lowest level of Hg intake (4.5 microg/person day(-1)), followed by La Gomera (5.4 microg/person day(-1)), Tenerife (5.5 microg/person day(-1)) and Gran Canaria (5.6 microg/person day(-1)). A comparison has been made of the results obtained in this study with those found for other national and international communities.

Effects of concurrent caffeine and mobile phone exposure on local target probability processing in the human brain

OpenAIRE

Trunk, Attila; Stefanics, Gábor; Zentai, Norbert; Bacskay, Ivett; Felinger, Attila; Thuróczy, György; Hernádi, István

2015-01-01

Millions of people use mobile phones (MP) while drinking coffee or other caffeine containing beverages. Little is known about the potential combined effects of MP irradiation and caffeine on cognitive functions. Here we investigated whether caffeine intake and concurrent exposure to Universal Mobile Telecommunications System (UMTS) MP-like irradiation may interactively influence neuro-cognitive function in an active visual oddball paradigm. In a full factorial experimental design, 25 particip...

"Wired," yet intoxicated: modeling binge caffeine and alcohol co-consumption in the mouse.

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Fritz, Brandon M; Companion, Michel; Boehm, Stephen L

2014-08-01

The combination of highly caffeinated "energy drinks" with alcohol (ethanol [EtOH]) has become popular among young adults and intoxication via such beverages has been associated with an elevated risk for harmful behaviors. However, there are discrepancies in the human literature regarding the effect of caffeine on alcohol intoxication, perhaps due to confounding factors such as personality type, expectancy, and history of exposure. Animal models of co-exposure are resistant to such issues; however, the consequences of voluntary co-consumption have been largely ignored in the animal literature. The primary goal of this work was to characterize a mouse model of binge caffeine and EtOH co-consumption employing the limited access "Drinking-in-the-Dark" (DID) paradigm. Caffeine was added to a 20% alcohol solution via DID. Alcohol/caffeine intake, locomotor behavior, ataxia, anxiety-like behavior, and cognitive function were evaluated as a consequence of co-consumption in adult male C57BL/6J mice. Caffeine did not substantially alter binge alcohol intake or resultant blood EtOH concentrations (BECs), nor did it alter alcohol's anxiolytic effects on the elevated plus maze or cognitive-interfering effects in a novel object-recognition task. However, no evidence of alcohol-induced sedation was observed in co-consumption groups that instead demonstrated a highly stimulated state similar to that of caffeine alone. The addition of caffeine was also found to mitigate alcohol-induced ataxia. Taken together, our mouse model indicates that binge co-consumption of caffeine and alcohol produces a stimulated, less ataxic and anxious, as well as cognitively altered state; a state that could be of great public health concern. These results appear to resemble the colloquially identified "wide awake drunk" state that individuals seek via consumption of such beverages. This self-administration model therefore offers the capacity for translationally valid explorations of the

Caffeine may enhance orthodontic tooth movement through increasing osteoclastogenesis induced by periodontal ligament cells under compression.

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Yi, Jianru; Yan, Boxi; Li, Meile; Wang, Yu; Zheng, Wei; Li, Yu; Zhao, Zhihe

2016-04-01

Caffeine is the kernel component of coffee and has multiple effects on bone metabolism. Here we aimed to investigate the effects of caffeine intake on orthodontic tooth movement (OTM). (1) In the in vivo study, two groups comprising 15 randomly assigned rats each underwent orthodontic treatment. One group ingested caffeine at 25mg/kg body weight per day and the other, plain water. After 3 weeks, the degree of tooth movement and effect on the periodontium were assessed. (2) In the in vitro study, we established a model mimicking the essential bioprocess of OTM, which contained a periodontal ligament tissue model (PDLtm), and a co-culture system of osteoblasts (OBs) and osteoclast precursors (pre-OCs). After being subjected to static compressive force with or without caffeine administration, the conditioned media from the PDLtm were used for the OB/pre-OC co-cultures to induce osteoclastogenesis. (1) In vivo, the caffeine group displayed a significantly greater rate of tooth movement than the control. The alveolar bone mineral density and bone volume fraction were similar between the two groups; however, immunohistochemical staining showed that the caffeine group had significantly more TRAP(+) osteoclasts and higher RANKL expression in the compressed periodontium. (2) In vitro, caffeine at 0.01mM significantly enhanced the compression-induced expression of RANKL and COX-2, as well as prostaglandin E2 production in the PDLtm. Furthermore, the "caffeine+compression"-conditioned media induced significantly more TRAP(+) OC formation when compared with compression alone. Daily intake of caffeine, at least at some specific dosage, may enhance OTM through increasing osteoclastogenesis. Copyright © 2016 Elsevier Ltd. All rights reserved.

Do caffeine-containing analgesics promote dependence? A review and evaluation.

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Feinstein, A R; Heinemann, L A; Dalessio, D; Fox, J M; Goldstein, J; Haag, G; Ladewig, D; O'Brien, C P

2000-11-01

Debates about the suspected association between kidney disease and use of analgesics have led to concern about whether caffeine could stimulate an undesirable overuse of phenacetin-free combined analgesics. A committee was asked to critically review the pertinent literature and to suggest guides for clinical practice and for consideration of international regulatory authorities. A group of international scientists, jointly selected by the regulatory authorities of Germany, Switzerland, and Austria and the pharmaceutical industry. All invited experts evaluated relevant literature and reports and added further information and comments. Caffeine has a synergistic effectiveness with analgesics. Although caffeine has a dependence potential, the potential is low. Experimental data regarding dependence potential for caffeine alone may not correspond to the conditions in patients with pain. Withdrawal is not likely to cause stimulation or sustainment of analgesic intake. For drug-induced headache, no single or combined analgesic was consistently identified as causative, and no evidence exists for a special role of caffeine. Strong dependence behavior was observed only in patients using phenacetin-containing preparations, coformulated with antipyretics/analgesics and caffeine. This finding may have led to the impression that caffeine stimulates overuse of analgesics. Although more experimental and long-term data would be desirable to show possible mechanisms of dependence and to offer unequivocal proof of safety, the committee concluded that the available evidence does not support the claim that analgesics coformulated with caffeine, in the absence of phenacetin, stimulate or sustain overuse.

Caffeine Improves Basketball Performance in Experienced Basketball Players

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Carlos Puente

2017-09-01

Full Text Available The aim of this study was to determine the effect of caffeine intake on overall basketball performance in experienced players. A double-blind, placebo-controlled, randomized experimental design was used for this investigation. In two different sessions separated by one week, 20 experienced basketball players ingested 3 mg of caffeine/kg of body mass or a placebo. After 60 min, participants performed 10 repetitions of the following sequence: Abalakov jump, Change-of-Direction and Acceleration Test (CODAT and two free throws. Later, heart rate, body impacts and game statistics were recorded during a 20-min simulated basketball game. In comparison to the placebo, the ingestion of caffeine increased mean jump height (37.3 ± 6.8 vs. 38.2 ± 7.4 cm; p = 0.012, but did not change mean time in the CODAT test or accuracy in free throws. During the simulated game, caffeine increased the number of body impacts (396 ± 43 vs. 410 ± 41 impacts/min; p < 0.001 without modifying mean or peak heart rate. Caffeine also increased the performance index rating (7.2 ± 8.6 vs. 10.6 ± 7.1; p = 0.037 during the game. Nevertheless, players showed a higher prevalence of insomnia (19.0 vs. 54.4%; p = 0.041 after the game. Three mg of caffeine per kg of body mass could be an effective ergogenic substance to increase physical performance and overall success in experienced basketball players.

Administration of Caffeine in Alternate Forms

OpenAIRE

Wickham, Kate A.; Spriet, Lawrence L.

2018-01-01

There has been recent interest in the ergogenic effects of caffeine delivered in low doses (~ 200 mg or ~ 3 mg/kg body mass) and administered in forms other than capsules, coffee and sports drinks, including chewing gum, bars, gels, mouth rinses, energy drinks and aerosols. Caffeinated chewing gum is absorbed quicker through the buccal mucosa compared with capsule delivery and absorption in the gut, although total caffeine absorption over time is not different. Rapid absorption may be importa...

Sex differences in the effects of pre- and postnatal caffeine exposure on behavior and synaptic proteins in pubescent rats.

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Sallaberry, Cássia; Ardais, Ana Paula; Rocha, Andréia; Borges, Maurício Felisberto; Fioreze, Gabriela T; Mioranzza, Sabrina; Nunes, Fernanda; Pagnussat, Natália; Botton, Paulo Henrique S; Porciúncula, Lisiane O

2018-02-02

Few studies have addressed the effects of caffeine in the puberty and/or adolescence in a sex dependent manner. Considering that caffeine intake has increased in this population, we investigated the behavioral and synaptic proteins changes in pubescent male and female rats after maternal consumption of caffeine. Adult female Wistar rats started to receive water or caffeine (0.1 and 0.3g/L in drinking water; low and moderate dose, respectively) during the active cycle at weekdays, two weeks before mating. The treatment lasted up to weaning and the offspring received caffeine until the onset of puberty (30-34days old). Behavioral tasks were performed to evaluate locomotor activity (open field task), anxious-like behavior (elevated plus maze task) and recognition memory (object recognition task) and synaptic proteins levels (proBDNF, BDNF, GFAP and SNAP-25) were verified in the hippocampus and cerebral cortex. While hyperlocomotion was observed in both sexes after caffeine treatment, anxiety-related behavior was attenuated by caffeine (0.3g/L) only in females. While moderate caffeine worsened recognition memory in females, an improvement in the long-term memory was observed in male rats for both doses. Coincident with memory improvement in males, caffeine increased pro- and BDNF in the hippocampus and cortex. Females presented increased proBDNF levels in both brain regions, with no effects of caffeine. While GFAP was not altered, moderate caffeine intake increased SNAP-25 in the cortex of female rats. Our findings revealed that caffeine promoted cognitive benefits in males associated with increased BDNF levels, while females showed less anxiety. Our findings revealed that caffeine promotes distinct behavioral outcomes and alterations in synaptic proteins during brain development in a sex dependent manner. Copyright © 2017 Elsevier Inc. All rights reserved.

A review of total & added sugar intakes and dietary sources in Europe.

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Azaïs-Braesco, Véronique; Sluik, Diewertje; Maillot, Matthieu; Kok, Frans; Moreno, Luis A

2017-01-21

Public health policies, including in Europe, are considering measures and recommendations to limit the intake of added or free sugars. For such policies to be efficient and monitored, a precise knowledge of the current situation regarding sugar intake in Europe is needed. This review summarizes published or re-analyzed data from 11 representative surveys in Belgium, France, Denmark, Hungary, Ireland, Italy, Norway, The Netherlands, Spain and the UK. Relative intakes were higher in children than in adults: total sugars ranged between 15 and 21% of energy intake in adults and between 16 and 26% in children. Added sugars (or non-milk extrinsic sugars (NMES), in the UK) contributed 7 to 11% of total energy intake in adults and represented a higher proportion of children's energy intake (11 to 17%). Educational level did not significantly affect intakes of total or added sugars in France and the Netherlands. Sweet products (e.g. confectionery, chocolates, cakes and biscuits, sugar, and jam) were major contributors to total sugars intake in all countries, genders and age groups, followed by fruits, beverages and dairy products. Fruits contributed more and beverages contributed less to adults' total sugars intakes than to children's. Added sugars were provided mostly by sweet products (36 to 61% in adults and 40 to 50% in children), followed by beverages (12 to 31% in adults and 20 to 34% in children, fruit juices excluded), then by dairy products (4 to 15% in adults and 6 to 18% in children). Caution is needed, however, as survey methodologies differ on important items such as dietary data collection, food composition tables or estimation of added sugars. Cross-country comparisons are thus not meaningful and overall information might thus not be robust enough to provide a solid basis for implementation of policy measures. Data nevertheless confirm that intakes of total and added sugars are high in the European countries considered, especially in children, and point to

Separating neural and vascular effects of caffeine using simultaneous EEG–FMRI: Differential effects of caffeine on cognitive and sensorimotor brain responses

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Diukova, Ana; Ware, Jennifer; Smith, Jessica E.; Evans, C. John; Murphy, Kevin; Rogers, Peter J.; Wise, Richard G.

2012-01-01

The effects of caffeine are mediated through its non-selective antagonistic effects on adenosine A1 and A2A adenosine receptors resulting in increased neuronal activity but also vasoconstriction in the brain. Caffeine, therefore, can modify BOLD FMRI signal responses through both its neural and its vascular effects depending on receptor distributions in different brain regions. In this study we aim to distinguish neural and vascular influences of a single dose of caffeine in measurements of task-related brain activity using simultaneous EEG–FMRI. We chose to compare low-level visual and motor (paced finger tapping) tasks with a cognitive (auditory oddball) task, with the expectation that caffeine would differentially affect brain responses in relation to these tasks. To avoid the influence of chronic caffeine intake, we examined the effect of 250 mg of oral caffeine on 14 non and infrequent caffeine consumers in a double-blind placebo-controlled cross-over study. Our results show that the task-related BOLD signal change in visual and primary motor cortex was significantly reduced by caffeine, while the amplitude and latency of visual evoked potentials over occipital cortex remained unaltered. However, during the auditory oddball task (target versus non-target stimuli) caffeine significantly increased the BOLD signal in frontal cortex. Correspondingly, there was also a significant effect of caffeine in reducing the target evoked response potential (P300) latency in the oddball task and this was associated with a positive potential over frontal cortex. Behavioural data showed that caffeine also improved performance in the oddball task with a significantly reduced number of missed responses. Our results are consistent with earlier studies demonstrating altered flow-metabolism coupling after caffeine administration in the context of our observation of a generalised caffeine-induced reduction in cerebral blood flow demonstrated by arterial spin labelling (19

Caffeine and the kidney: what evidence right now?

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Bolignano, Davide; Coppolino, Giuseppe; Barillà, Antonio; Campo, Susanna; Criseo, Manila; Tripodo, Donatella; Buemi, Michele

2007-07-01

Caffeine, or 1, 3, 7-trimethylxanthine, is one of the most frequently consumed active drugs worldwide. Its main mechanisms of action include inhibiting the phosphodiesteratic enzyme and adenosine receptors and activating the ryanodine receptors with several actions on all organs. What effect does caffeine have on the kidney? Is caffeine beneficial or dangerous? A review of the current literature reveals conflicting opinions regarding the prolithiasic effect of this substance, whereas its diuretic action is least disputed and more easily observed. Caffeine may have a toxic or preventive effect in some physiologic or pathologic conditions. Some of these incongruences may depend on several factors, such as dosage, prior chronic exposure, genetic-enzymatic axes, and concomitant drug consumption. While awaiting further insight from forthcoming studies on the issue, we may reach a preliminary conclusion that, as yet, there is no evidence contraindicating the consumption of the equivalent of 3 to 4 cups of coffee per day in healthy or nephropathic subjects. However, particular attention should be paid to the elderly, children, and patients on concomitant treatment with analgesics or diuretics, whereas in subjects with a family or clinical history of calcium lithiasis a moderate caffeine consumption should be associated with an adequate fluid intake. Further in-depth studies are required to investigate whether this beverage is beneficial to patients on hemodialysis.

Determination of dietary intake of total arsenic, inorganic arsenic and total mercury in the Chilean school meal program.

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Bastías, J M; Bermúdez, M; Carrasco, J; Espinoza, O; Muñoz, M; Galotto, M J; Muñoz, O

2010-10-01

The dietary intake of total arsenic (tAs), inorganic arsenic (iAs) and total mercury (tHg) in lunch and breakfast servings provided by the Chilean School Meal Program (SMP) was estimated, using the duplicate-portion variant of the total diet study. Lunch and breakfast samples were collected from 65 schools throughout the country in 2006. The population sample was a group of girls and boys between 6 and 18 years old. The tAs concentration was measured via hydride-generation atomic absorption spectrometry. The total mercury concentration was measured via cold-vapor atomic absorption spectroscopy. The estimated iAs intake was 12.5% (5.4 μg/day) of the Provisional tolerable daily intake (PTDI) as proposed by the FAO/WHO, and the tHg intake was 13.2% (1.9 μg/day) of the PTDI as proposed by the FAO/WHO. It was therefore concluded that tAs, iAs and tHg intake from food provided by the SMP do not pose risks to student health.

Effects of total fat intake on bodyweight in children.

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Naude, Celeste E; Visser, Marianne E; Nguyen, Kim A; Durao, Solange; Schoonees, Anel

2018-02-15

As part of efforts to prevent childhood overweight and obesity, we need to understand the relationship between total fat intake and body fatness in generally healthy children. To assess the effects of total fat intake on measures of weight and body fatness in children and young people not aiming to lose weight. For this update we revised the previous search strategy and ran it over all years in the Cochrane Library, MEDLINE (Ovid), MEDLINE (PubMed), and Embase (Ovid) (current to 23 May 2017). No language and publication status limits were applied. We searched the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov for ongoing and unpublished studies (5 June 2017). We included randomised controlled trials (RCTs) in children aged 24 months to 18 years, with or without risk factors for cardiovascular disease, randomised to a lower fat (30% or less of total energy (TE)) versus usual or moderate-fat diet (greater than 30%TE), without the intention to reduce weight, and assessed a measure of weight or body fatness after at least six months. We included prospective analytical cohort studies in these children if they related baseline total fat intake to weight or body fatness at least 12 months later. We duplicated inclusion decisions and resolved disagreement by discussion with other authors. We extracted data on participants, interventions or exposures, controls and outcomes, and trial or cohort quality characteristics, as well as data on potential effect modifiers, and assessed risk of bias for all included studies. We extracted outcome data using the following time point ranges, when available: RCTs: baseline to six months, six to 12 months, one to two years, two to five years and more than five years; cohort studies: baseline to one year, one to two years, two to five years, five to 10 years and more than 10 years. We planned to perform random-effects meta-analyses with relevant subgrouping, and sensitivity and funnel plot

Caffeine

Science.gov (United States)

What is caffeine? Caffeine is a bitter substance that occurs naturally in more than 60 plants including Coffee beans Tea leaves Kola nuts, ... chocolate products There is also synthetic (man-made) caffeine, which is added to some medicines, foods, and ...

Caffeine increases sugar-sweetened beverage consumption in a free-living population: a randomised controlled trial.

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Keast, Russell S J; Swinburn, Boyd A; Sayompark, Dhoungsiri; Whitelock, Susie; Riddell, Lynn J

2015-01-28

Excessive sugar-sweetened beverage (SSB) consumption has been associated with overweight and obesity. Caffeine is a common additive to SSB, and through dependence effects, it has the potential to promote the consumption of caffeine-containing foods. The objective of the present study was to assess the influence that caffeine has on the consumption of SSB. Participants (n 99) were blindly assigned to either a caffeinated SSB (C-SSB) or a non-caffeinated SSB (NC-SSB) group. Following randomisation, all participants completed a 9 d flavour-conditioning paradigm. They then completed a 28 d ad libitum intake intervention where they consumed as much or as little of C-SSB or NC-SSB as desired. The amount consumed (ml) was recorded daily, 4 d diet diaries were collected and liking of SSB was assessed at the start and end of the intervention. Participants (n 50) consuming the C-SSB had a daily SSB intake of 419 (sd 298) ml (785 (sd 559) kJ/d) over the 28 d intervention, significantly more than participants (n 49) consuming the NC-SSB (273 (sd 278) ml/d, 512 (sd 521) kJ/d) (P=0.05). However, participants who consumed the C-SSB liked the SSB more than those who consumed the NC-SSB (6.3 v. 6.0 on a nine-point hedonic scale, P= 0.022). The addition of low concentrations of caffeine to the SSB significantly increases the consumption of the SSB. Regulating caffeine as a food additive may be an effective strategy to decrease the consumption of nutrient-poor high-energy foods and beverages.

Caffeine, postmenopausal estrogen, and risk of Parkinson's disease.

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Ascherio, A; Chen, H; Schwarzschild, M A; Zhang, S M; Colditz, G A; Speizer, F E

2003-03-11

Men who regularly consume caffeinated drinks have a lower risk of PD than do nondrinkers, but this relation has not been found in women. Because this sex difference could be due to hormonal effects, the authors examined prospectively the risk of PD according to use of postmenopausal hormones and caffeine intake among participants in the Nurses' Health Study. The study population comprised 77,713 women free of PD, stroke, or cancer at baseline, who were postmenopausal at baseline or reached menopause before the end of the study. During 18 years of follow-up the authors documented 154 cases of PD. Overall, the risk of PD was similar in women using hormones and women who never used hormones (relative risk 1.02, 95% CI 0.69 to 1.52). Use of hormones, however, was associated with a reduced risk of PD among women with low caffeine consumption (RR 0.39, 95% CI 0.13 to 1.17), and with increased risk among women with high caffeine consumption (RR 2.44, 95% CI 0.75 to 7.86; p for interaction = 0.01). Among hormone users, women consuming six or more cups of coffee per day had a fourfold higher risk of PD (RR 3.92, 95% CI 1.49 to 10.34; p = 0.006) than did women who never drink coffee. These results suggest that caffeine reduces the risk of PD among women who do not use postmenopausal hormones, but increases risk among hormone users. Clinical trials of caffeine or estrogens in women should avoid the combined use of these agents.

Caffeine improves muscular performance in elite Brazilian Jiu-jitsu athletes.

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Diaz-Lara, Francisco Javier; Del Coso, Juan; García, Jose Manuel; Portillo, Luis J; Areces, Francisco; Abián-Vicén, Javier

2016-11-01

Scientific information about the effects of caffeine intake on combat sport performance is scarce and controversial. The aim of this study was to investigate the effectiveness of caffeine to improve Brazilian Jiu-jitsu (BJJ)-specific muscular performance. Fourteen male and elite BJJ athletes (29.2 ± 3.3 years; 71.3 ± 9.1 kg) participated in a randomized double-blind, placebo-controlled and crossover experiment. In two different sessions, BJJ athletes ingested 3 mg kg(-1) of caffeine or a placebo. After 60 min, they performed a handgrip maximal force test, a countermovement jump, a maximal static lift test and bench-press tests consisting of one-repetition maximum, power-load, and repetitions to failure. In comparison to the placebo, the ingestion of the caffeine increased: hand grip force in both hands (50.9 ± 2.9 vs. 53.3 ± 3.1 kg; respectively p caffeine also increased the one-repetition maximum (90.5 ± 7.7 vs. 93.3 ± 7.5 kg; p = .02), maximal power obtained during the power-load test (750.5 ± 154.7 vs. 826.9 ± 163.7 W; p caffeine increased dynamic and isometric muscular force, power, and endurance strength in elite BJJ athletes. Thus, caffeine might be an effective ergogenic aid to improve physical performance in BJJ.

Caffeine exposure and the risk of Parkinson's disease: a systematic review and meta-analysis of observational studies.

Science.gov (United States)

Costa, João; Lunet, Nuno; Santos, Catarina; Santos, João; Vaz-Carneiro, António

2010-01-01

Several studies conducted worldwide report an inverse association between caffeine/coffee consumption and the risk of developing Parkinson's disease (PD). However, heterogeneity and conflicting results between studies preclude a correct estimation of the strength of this association. We conducted a systematic review and meta-analysis of published epidemiological studies to better estimate the effect of caffeine exposure on the incidence of PD. Data sources searched included Medline, LILACS, Scopus, Web of Science and reference lists, up to September 2009. Cohort, case-control and cross-sectional studies were included. Three independent reviewers selected the studies and extracted the data on to standardized forms. Twenty-six studies were included: 7 cohort, 2 nested case-control, 16 case-control, and 1 cross-sectional study. Quantitative data synthesis of the most precise estimates from each study was accomplished through random effects meta-analysis. Heterogeneity was quantified using the I2 statistic. The summary RR for the association between caffeine intake and PD was 0.75 [[95% Confidence Interval (95%CI): 0.68-0.82], with low to moderate heterogeneity (I2= 28.8%). Publication bias for case-control/cross-sectional studies may exist (Egger's test, p=0.053). When considering only the cohort studies, the RR was 0.80 (95%CI: 0.71-90; I2=8.1%). The negative association was weaker when only women were considered (RR=0.86, 95%CI: 0.73-1.02; I2=12.9%). A linear relation was observed between levels of exposure to caffeine and the RR estimates: RR of 0.76 (95%CI: 0.72-0.80; I2= 35.1%) per 300 mg increase in caffeine intake. This study confirm an inverse association between caffeine intake and the risk of PD, which can hardly by explained by bias or uncontrolled confounding.

effect of caffeine -coconut products interactions on induction of ...

African Journals Online (AJOL)

INDUCTION OF MICROSOMAL DRUG-METABOLIZING ENZYMES IN ... examine several biochemical parameters, ie, total protein and RNA levels, ... Caffeine also acts to increase alertness, ... Mechanisms of action of caffeine involve.

Caffeine and cognitive performance: persistent methodological challenges in caffeine research.

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James, Jack E

2014-09-01

Human cognitive performance is widely perceived to be enhanced by caffeine at usual dietary doses. However, the evidence for and against this belief continues to be vigorously contested. Controversy has centred on caffeine withdrawal and withdrawal reversal as potential sources of experimental confounding. In response, some researchers have enlisted "caffeine-naïve" experimental participants (persons alleged to consume little or no caffeine) assuming that they are not subject to withdrawal. This mini-review examines relevant research to illustrate general methodological challenges that have been the cause of enduring confusion in caffeine research. At issue are the processes of caffeine withdrawal and withdrawal reversal, the definition of caffeine-naïve, the population representativeness of participants deemed to be caffeine-naïve, and confounding due to caffeine tolerance. Attention to these processes is necessary if premature conclusions are to be avoided, and if caffeine's complex effects and the mechanisms responsible for those effects are to be illuminated. Strategies are described for future caffeine research aimed at minimising confounding from withdrawal and withdrawal reversal. Copyright © 2014 Elsevier Inc. All rights reserved.

Caffein

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Nørager, Charlotte Buchard; Jensen, Martin Bach; Madsen, Mogens Rørbæk

2005-01-01

/kg) can increase the endurance of athletes engaged in running, bicycling, swimming and other endurance sports. Caffeine is used both in training and in competitions, and the International Olympic Commitée (IOC) has included caffeine as a drug used for doping. There are several theories about caffeine...

Does long-term coffee intake reduce type 2 diabetes mellitus risk?

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Pimentel Gustavo D

2009-09-01

Full Text Available Abstract This review reports the evidence for a relation between long-term coffee intake and risk of type 2 diabetes mellitus. Numerous epidemiological studies have evaluated this association and, at this moment, at least fourteen out of eighteen cohort studies revealed a substantially lower risk of type 2 diabetes mellitus with frequent coffee intake. Moderate coffee intake (≥4 cups of coffee/d of 150 mL or ≥400 mg of caffeine/d has generally been associated with a decrease in the risk of type 2 diabetes mellitus. Besides, results of most studies suggest a dose-response relation, with greater reductions in type 2 diabetes mellitus risk with higher levels of coffee consumption. Several mechanisms underlying this protective effect, as well as the coffee components responsible for this association are suggested. Despite positive findings, it is still premature to recommend an increase in coffee consumption as a public health strategy to prevent type 2 diabetes mellitus. More population-based surveys are necessary to clarify the long-term effects of decaffeinated and caffeinated coffee intake on the risk of type 2 diabetes mellitus.

Coffee, tea, caffeine, and risk of hypertension: The Singapore Chinese Health Study.

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Chei, Choy-Lye; Loh, Julian Kenrick; Soh, Avril; Yuan, Jian-Min; Koh, Woon-Puay

2018-06-01

The relationship between coffee and tea, and risk of hypertension remains controversial in Western populations. We investigated these associations in an Asian population. The Singapore Chinese Health Study is a population-based prospective cohort that recruited 63,257 Chinese aged 45-74 years and residing in Singapore from 1993 to 1998. Information on consumption of coffee, tea, and other lifestyle factors was collected at baseline, and self-reported physician-diagnosed hypertension was assessed during two follow-up interviews (1999-2004, 2006-2010). We identified 13,658 cases of incident hypertension after average 9.5 years. Compared to those who drank one cup of coffee/day, the hazard ratios (HR) and 95% confidence intervals (CI) were 0.87 (0.83-0.91) for caffeine. After adjusting for coffee, there was a stepwise dose-response relationship between caffeine intake and hypertension risk; compared to the lowest intake (<50 mg/day), those in the highest intake (≥300 mg/day) had a 16% increase in risk; HR 1.16, 95% CI 1.04-1.31 (p trend = 0.02). Drinking coffee <1 cup/week or ≥3 cups/day had lower risk than drinking one cup/day. Caffeine may account for increased risk in daily tea drinkers and in those who drank one cup of coffee/day. The inverse U-shaped association with coffee suggests that at higher doses, other ingredients in coffee may offset the effect of caffeine and confer benefit on blood pressure.

Caffeine Induces the Stress Response and Up-Regulates Heat Shock Proteins in Caenorhabditis elegans.

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Al-Amin, Mohammad; Kawasaki, Ichiro; Gong, Joomi; Shim, Yhong-Hee

2016-02-01

Caffeine has both positive and negative effects on physiological functions in a dose-dependent manner. C. elegans has been used as an animal model to investigate the effects of caffeine on development. Caffeine treatment at a high dose (30 mM) showed detrimental effects and caused early larval arrest. We performed a comparative proteomic analysis to investigate the mode of action of high-dose caffeine treatment in C. elegans and found that the stress response proteins, heat shock protein (HSP)-4 (endoplasmic reticulum [ER] chaperone), HSP-6 (mitochondrial chaperone), and HSP-16 (cytosolic chaperone), were induced and their expression was regulated at the transcriptional level. These findings suggest that high-dose caffeine intake causes a strong stress response and activates all three stress-response pathways in the worms, including the ER-, mitochondrial-, and cytosolic pathways. RNA interference of each hsp gene or in triple combination retarded growth. In addition, caffeine treatment stimulated a food-avoidance behavior (aversion phenotype), which was enhanced by RNAi depletion of the hsp-4 gene. Therefore, up-regulation of hsp genes after caffeine treatment appeared to be the major responses to alleviate stress and protect against developmental arrest.

Coffee intake, cardiovascular disease and all-cause mortality: observational and Mendelian randomization analyses in 95 000-223 000 individuals.

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Nordestgaard, Ask Tybjærg; Nordestgaard, Børge Grønne

2016-12-01

Coffee has been associated with modestly lower risk of cardiovascular disease and all-cause mortality in meta-analyses; however, it is unclear whether these are causal associations. We tested first whether coffee intake is associated with cardiovascular disease and all-cause mortality observationally; second, whether genetic variations previously associated with caffeine intake are associated with coffee intake; and third, whether the genetic variations are associated with cardiovascular disease and all-cause mortality. First, we used multivariable adjusted Cox proportional hazard regression models evaluated with restricted cubic splines to examine observational associations in 95 366 White Danes. Second, we estimated mean coffee intake according to five genetic variations near the AHR (rs4410790; rs6968865) and CYP1A1/2 genes (rs2470893; rs2472297; rs2472299). Third, we used sex- and age adjusted Cox proportional hazard regression models to examine genetic associations with cardiovascular disease and all-cause mortality in 112 509 Danes. Finally, we used sex and age-adjusted logistic regression models to examine genetic associations with ischaemic heart disease including the Cardiogram and C4D consortia in a total of up to 223 414 individuals. We applied similar analyses to ApoE genotypes associated with plasma cholesterol levels, as a positive control. In observational analyses, we observed U-shaped associations between coffee intake and cardiovascular disease and all-cause mortality; lowest risks were observed in individuals with medium coffee intake. Caffeine intake allele score (rs4410790 + rs2470893) was associated with a 42% higher coffee intake. Hazard ratios per caffeine intake allele were 1.02 (95% confidence interval: 1.00-1.03) for ischaemic heart disease, 1.02 (0.99-1.02) for ischaemic stroke, 1.02 (1.00-1.03) for ischaemic vascular disease, 1.02 (0.99-1.06) for cardiovascular mortality and 1.01 (0.99-1.03) for all-cause mortality. Including

[Caffeine dependence].

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Ogawa, Naoshi; Ueki, Hirofumi

2010-08-01

Caffeine is the most widely consumed psychoactive substance in the world and is a legal stimulant that is readily available to children. The potential for dependence on caffeine has been debated. Presently, due to a paucity of clinical evidence on caffeine dependence, no such diagnosis is included in the Diagnostic and Statistical Manual of Mental Disorders Fourth Edition, Text Revision (DSM-IV-TR). Although in recent studies, a subset of the general population was found to demonstrate caffeine dependence. It is valuable for psychiatrists and primary care physicians to recognize caffeine dependence as a clinical syndrome, since some people are distressed by their caffeine use and feel they can not control or stop their problematic use.

Acute Ingestion of Caffeinated Chewing Gum Improves Repeated Sprint Performance of Team Sport Athletes With Low Habitual Caffeine Consumption.

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Evans, Mark; Tierney, Peter; Gray, Nicola; Hawe, Greg; Macken, Maria; Egan, Brendan

2018-04-23

The effects of acute ingestion of caffeine on short-duration high-intensity performance are equivocal, while studies of novel modes of delivery and the efficacy of low doses of caffeine are warranted. The aims of the present study were to investigate the effect of acute ingestion of caffeinated chewing gum on repeated sprint performance (RSP) in team sport athletes, and whether habitual caffeine consumption alters the ergogenic effect, if any, on RSP. A total of 18 male team sport athletes undertook four RSP trials using a 40-m maximum shuttle run test, which incorporates 10 × 40-m sprints with 30 s between the start of each sprint. Each participant completed two familiarization sessions, followed by caffeine (CAF; caffeinated chewing gum; 200 mg caffeine) and placebo (PLA; noncaffeinated chewing gum) trials in a randomized, double-blind manner. RSP, assessed by sprint performance decrement (%), did not differ (p = .209; effect size = 0.16; N = 18) between CAF (5.00 ± 2.84%) and PLA (5.43 ± 2.68%). Secondary analysis revealed that low habitual caffeine consumers (130 mg/day, n = 6; 3.98 ± 2.57% vs. 3.80 ± 1.79%, respectively; p = .684; effect size = 0.08). The data suggest that a low dose of caffeine in the form of caffeinated chewing gum attenuates the sprint performance decrement during RSP by team sport athletes with low, but not moderate-to-high, habitual consumption of caffeine.

Systematic review of the potential adverse effects of caffeine consumption in healthy adults, pregnant women, adolescents, and children.

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Wikoff, Daniele; Welsh, Brian T; Henderson, Rayetta; Brorby, Gregory P; Britt, Janice; Myers, Esther; Goldberger, Jeffrey; Lieberman, Harris R; O'Brien, Charles; Peck, Jennifer; Tenenbein, Milton; Weaver, Connie; Harvey, Seneca; Urban, Jonathan; Doepker, Candace

2017-11-01

To date, one of the most heavily cited assessments of caffeine safety in the peer-reviewed literature is that issued by Health Canada (Nawrot et al., 2003). Since then, >10,000 papers have been published related to caffeine, including hundreds of reviews on specific human health effects; however, to date, none have compared the wide range of topics evaluated by Nawrot et al. (2003). Thus, as an update to this foundational publication, we conducted a systematic review of data on potential adverse effects of caffeine published from 2001 to June 2015. Subject matter experts and research team participants developed five PECO (population, exposure, comparator, and outcome) questions to address five types of outcomes (acute toxicity, cardiovascular toxicity, bone and calcium effects, behavior, and development and reproduction) in four healthy populations (adults, pregnant women, adolescents, and children) relative to caffeine intake doses determined not to be associated with adverse effects by Health Canada (comparators: 400 mg/day for adults [10 g for lethality], 300 mg/day for pregnant women, and 2.5 mg/kg/day for children and adolescents). The a priori search strategy identified >5000 articles that were screened, with 381 meeting inclusion/exclusion criteria for the five outcomes (pharmacokinetics was addressed contextually, adding 46 more studies). Data were extracted by the research team and rated for risk of bias and indirectness (internal and external validity). Selected no- and low-effect intakes were assessed relative to the population-specific comparator. Conclusions were drawn for the body of evidence for each outcome, as well as endpoints within an outcome, using a weight of evidence approach. When the total body of evidence was evaluated and when study quality, consistency, level of adversity, and magnitude of response were considered, the evidence generally supports that consumption of up to 400 mg caffeine/day in healthy adults is not associated

Effects of preweaning total plane of milk intake and weaning age on intake, growth performance, and blood metabolites of dairy calves.

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Mirzaei, M; Dadkhah, N; Baghbanzadeh-Nobari, B; Agha-Tehrani, A; Eshraghi, M; Imani, M; Shiasi-Sardoabi, R; Ghaffari, M H

2018-05-01

The objective of this study was to evaluate the effects of preweaning total plane of milk intake and weaning age on intake, growth performance, and blood metabolites of dairy calves. A total of 48 Holstein calves (40 ± 1.6 kg of body weight) were used in a 2 × 2 factorial arrangement with the factors of weaning age (d 60 vs. 75) and the total plane of milk intake (medium vs. high) during the preweaning period. Calves were assigned to 1 of 4 treatments: (1) calves fed medium plane of milk (MPM) intake and weaned on d 60 of age (MPM-60d, 4 L/d of milk from d 3 to 10, 6 L/d of milk from d 11 to 55, and 3 L/d of milk from d 56 to 60 of age; total milk intake = 317 L), (2) calves fed MPM intake and weaned on d 75 of age (MPM-75d, 4 L/d of milk from d 3 to 10 and 4.5 L/d of milk from d 11 to 70 of age followed by feeding 2.25 L/d of milk from d 71 to 75 of age; total milk intake = 313 L), (3) calves fed high plane of milk (HPM) intake and weaned on d 60 of age (HPM-60d, 4 L/d of milk from d 3 to 10, 6 L/d of milk from d 11 to 20, and 8.5 L/d of milk from d 21 to 55 followed by feeding 4.25 L/d of milk from d 56 to 60 of age; total milk intake = ∼411 L); and (4) calves fed HPM intake and weaned on d 75 (HPM-75d, 4 L/d of milk from d 3 to 10, and 6 L/d of milk from d 11 to 70 of age followed by feeding 3 L/d of milk from d 71 to 75 of age; total milk intake = 407 L) with no milk refusals. All of the calves were monitored up to d 90 of age. Regardless of weaning age, starter feed intake and dry matter intake (% of body weight) were lower in calves fed HPM compared with those receiving MPM. A tendency for the plane of milk intake × weaning age interaction was observed for metabolizable energy intake with the highest value was recorded with the HPM-75d calves. The lowest efficiency of metabolizable energy intake and average feed efficiency was observed in HPM-60d calves throughout the experimental period as compared with the other groups. An interaction was found between

Make Caffeine Visible: a Fluorescent Caffeine “Traffic Light” Detector

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Xu, Wang; Kim, Tae-Hyeong; Zhai, Duanting; Er, Jun Cheng; Zhang, Liyun; Kale, Anup Atul; Agrawalla, Bikram Keshari; Cho, Yoon-Kyoung; Chang, Young-Tae

2013-07-01

Caffeine has attracted abundant attention due to its extensive existence in beverages and medicines. However, to detect it sensitively and conveniently remains a challenge, especially in resource-limited regions. Here we report a novel aqueous phase fluorescent caffeine sensor named Caffeine Orange which exhibits 250-fold fluorescence enhancement upon caffeine activation and high selectivity. Nuclear magnetic resonance spectroscopy and Fourier transform infrared spectroscopy indicate that π-stacking and hydrogen-bonding contribute to their interactions while dynamic light scattering and transmission electron microscopy experiments demonstrate the change of Caffeine Orange ambient environment induces its fluorescence emission. To utilize this probe in real life, we developed a non-toxic caffeine detection kit and tested it for caffeine quantification in various beverages. Naked-eye sensing of various caffeine concentrations was possible based on color changes upon irradiation with a laser pointer. Lastly, we performed the whole system on a microfluidic device to make caffeine detection quick, sensitive and automated.

Analysis of Total Food Intake and Composition of Individual's ...

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EPA released the final report, Analysis of Total Food Intake and Composition of Individual’s Diet Based on USDA’s 1994-1996, 98 Continuing Survey of Food Intakes by Individuals (CSFII). The consumption of food by the general population is a significant route of potential exposure to hazardous substances that are present in the environment. For this reason, a thorough analysis of the dietary habits of the American public would aid in the identification of potential exposure pathways. To that end, the EPA developed per capita food intake rates for various food items and food categories using databases developed by the United States Department of Agriculture (USDA). These intake rates were incorporated into EPA's 1997 Exposure Factors Handbook. Since that time, EPA has recommended that the food intake study be updated and expanded to include a more comprehensive analysis of food intake. That analysis is presented in this document. The purpose of this study is to characterize the consumption of food by the people of the United States.

Estimated Intakes and Sources of Total and Added Sugars in the Canadian Diet

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Tristin D. Brisbois

2014-05-01

Full Text Available National food supply data and dietary surveys are essential to estimate nutrient intakes and monitor trends, yet there are few published studies estimating added sugars consumption. The purpose of this report was to estimate and trend added sugars intakes and their contribution to total energy intake among Canadians by, first, using Canadian Community Health Survey (CCHS nutrition survey data of intakes of sugars in foods and beverages, and second, using Statistics Canada availability data and adjusting these for wastage to estimate intakes. Added sugars intakes were estimated from CCHS data by categorizing the sugars content of food groups as either added or naturally occurring. Added sugars accounted for approximately half of total sugars consumed. Annual availability data were obtained from Statistics Canada CANSIM database. Estimates for added sugars were obtained by summing the availability of “sugars and syrups” with availability of “soft drinks” (proxy for high fructose corn syrup and adjusting for waste. Analysis of both survey and availability data suggests that added sugars average 11%–13% of total energy intake. Availability data indicate that added sugars intakes have been stable or modestly declining as a percent of total energy over the past three decades. Although these are best estimates based on available data, this analysis may encourage the development of better databases to help inform public policy recommendations.

Estimated intakes and sources of total and added sugars in the Canadian diet.

Science.gov (United States)

Brisbois, Tristin D; Marsden, Sandra L; Anderson, G Harvey; Sievenpiper, John L

2014-05-08

National food supply data and dietary surveys are essential to estimate nutrient intakes and monitor trends, yet there are few published studies estimating added sugars consumption. The purpose of this report was to estimate and trend added sugars intakes and their contribution to total energy intake among Canadians by, first, using Canadian Community Health Survey (CCHS) nutrition survey data of intakes of sugars in foods and beverages, and second, using Statistics Canada availability data and adjusting these for wastage to estimate intakes. Added sugars intakes were estimated from CCHS data by categorizing the sugars content of food groups as either added or naturally occurring. Added sugars accounted for approximately half of total sugars consumed. Annual availability data were obtained from Statistics Canada CANSIM database. Estimates for added sugars were obtained by summing the availability of "sugars and syrups" with availability of "soft drinks" (proxy for high fructose corn syrup) and adjusting for waste. Analysis of both survey and availability data suggests that added sugars average 11%-13% of total energy intake. Availability data indicate that added sugars intakes have been stable or modestly declining as a percent of total energy over the past three decades. Although these are best estimates based on available data, this analysis may encourage the development of better databases to help inform public policy recommendations.

Crude caffeine reduces memory impairment and amyloid β(1-42) levels in an Alzheimer's mouse model.

Science.gov (United States)

Chu, Yi-Fang; Chang, Wen-Han; Black, Richard M; Liu, Jia-Ren; Sompol, Pradoldej; Chen, Yumin; Wei, Huilin; Zhao, Qiuyan; Cheng, Irene H

2012-12-01

Alzheimer's disease (AD), a chronic neurodegenerative disorder associated with the abnormal accumulations of amyloid β (Aβ) peptide and oxidative stress in the brain, is the most common form of dementia among the elderly. Crude caffeine (CC), a major by-product of the decaffeination of coffee, has potent hydrophilic antioxidant activity and may reduce inflammatory processes. Here, we showed that CC and pure caffeine intake had beneficial effects in a mouse model of AD. Administration of CC or pure caffeine for 2months partially prevented memory impairment in AD mice, with CC having greater effects than pure caffeine. Furthermore, consumption of CC, but not pure caffeine, reduced the Aβ(1-42) levels and the number of amyloid plaques in the hippocampus. Moreover, CC and caffeine protected primary neurons from Aβ-induced cell death and suppressed Aβ-induced caspase-3 activity. Our data indicate that CC may contain prophylactic agents against the cell death and the memory impairment in AD. Copyright © 2012 Elsevier Ltd. All rights reserved.

Enhancing physical performance in male volleyball players with a caffeine-containing energy drink.

Science.gov (United States)

Del Coso, Juan; Pérez-López, Alberto; Abian-Vicen, Javier; Salinero, Juan Jose; Lara, Beatriz; Valadés, David

2014-11-01

There are no scientific data about the effects of caffeine intake on volleyball performance. The aim of this study was to investigate the effect of a caffeine-containing energy drink to enhance physical performance in male volleyball players. A double-blind, placebo-controlled, randomized experimental design was used. In 2 different sessions separated by 1 wk, 15 college volleyball players ingested 3 mg of caffeine per kg of body mass in the form of an energy drink or the same drink without caffeine (placebo). After 60 min, participants performed volleyball-specific tests: standing spike test, maximal squat jump (SJ), maximal countermovement jump (CMJ), 15-s rebound jump test (15RJ), and agility T-test. Later, a simulated volleyball match was played and recorded. In comparison with the placebo drink, the ingestion of the caffeinated energy drink increased ball velocity in the spike test (73 ± 9 vs 75 ± 10 km/h, P volleyball actions more frequently (24.6% ± 14.3% vs 34.3% ± 16.5%, P volleyball players.

Polyamines: total daily intake in adolescents compared to the intake estimated from the Swedish Nutrition Recommendations Objectified (SNO

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Mohamed Atiya Ali

2011-01-01

Full Text Available Background: Dietary polyamines have been shown to give a significant contribution to the body pool of polyamines. Knowing the levels of polyamines (putrescine, spermidine, and spermine in different foods and the contribution of daily food choice to polyamine intake is of interest, due to the association of these bioactive amines to health and disease. Objective: To estimate polyamine intake and food contribution to this intake in adolescents compared to a diet fulfilling the Swedish Nutrition Recommendations. Design: A cross-sectional study of dietary intake in adolescents and an ‘ideal diet’ (Swedish nutrition recommendations objectified [SNO] list of foods was used to compute polyamine intake using a database of polyamine contents of foods. For polyamine intake estimation, 7-day weighed food records collected from 93 adolescents were entered into dietetic software (Dietist XP including data on polyamine contents of foods. The content of polyamines in foods recommended according to SNO was entered in the same way. Results: The adolescents’ mean daily polyamine intake was 316±170 µmol/day, while the calculated contribution according to SNO was considerably higher with an average polyamine intake of 541 µmol/day. In both adolescent's intake and SNO, fruits contributed to almost half of the total polyamine intake. The reason why the intake among the adolescents was lower than the one calculated from SNO was mainly due to the low vegetable consumption in the adolescents group. Conclusions: The average daily total polyamine intake was similar to that previously reported in Europe. With an ‘ideal’ diet according to Swedish nutrition recommendations, the intake of this bioactive non-nutrient would be higher than that reported by our adolescents and also higher than that previously reported from Europe.

Intake of total and added sugars and nutrient dilution in Australian children and adolescents.

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Louie, Jimmy Chun Yu; Tapsell, Linda C

2015-12-14

This analysis aimed to examine the association between intake of sugars (total or added) and nutrient intake with data from a recent Australian national nutrition survey, the 2007 Australian National Children's Nutrition and Physical Activity Survey (2007ANCNPAS). Data from participants (n 4140; 51 % male) who provided 2×plausible 24-h recalls were included in the analysis. The values on added sugars for foods were estimated using a previously published ten-step systematic methodology. Reported intakes of nutrients and foods defined in the 2007ANCNPAS were analysed by age- and sex-specific quintiles of %energy from added sugars (%EAS) or %energy from total sugars (%ETS) using ANCOVA. Linear trends across the quintiles were examined using multiple linear regression. Logistic regression analysis was used to calculate the OR of not meeting a specified nutrient reference values for Australia and New Zealand per unit in %EAS or %ETS. Analyses were adjusted for age, sex, BMI z-score and total energy intake. Small but significant negative associations were seen between %EAS and the intakes of most nutrient intakes (all Padded sugars were associated with lower intakes of most nutrient-rich, 'core' food groups and higher intakes of energy-dense, nutrient-poor 'extra' foods. In conclusion, assessing intakes of added sugars may be a better approach for addressing issues of diet quality compared with intakes of total sugars.

Beneficial Role of Coffee and Caffeine in Neurodegenerative Diseases: A Minireview

Directory of Open Access Journals (Sweden)

Yenisetti SC

2016-06-01

Full Text Available Coffee is among the most widespread and healthiest beverages in the world. Coffee typically contains more caffeine than most other beverages, and is widely and frequently consumed. Thus, it contributes significantly to the overall caffeine consumption within the general population, particularly in adults. Controversies regarding its benefits and risks still exist as reliable evidence is becoming available supporting its health-promoting potential. Several lines of evidence have highlighted the beneficial effects towards several disease conditions including Type II diabetes, hepatitis C virus, hepatocellular carcinoma, nonalcoholic fatty liver disease and neurodegenerative disorders such as Alzheimer's disease (AD, Parkinson's disease (PD and Amyotrophic Lateral Sclerosis (ALS. The health-promoting properties of coffee are largely attributed to its rich phytochemistry, including caffeine, chlorogenic acid, caffeic acid, and hydroxy hydroquinone. In this minireview, an attempt has been made to discuss the various evidences which are mainly derived from animal and cell models. Various mechanisms chiefly responsible for the beneficial effects of caffeine have also been briefly outlined. A short note on the undesirable effects of excessive coffee intakes is also presented.

Determination of the caffeine contents of various food items within the Austrian market and validation of a caffeine assessment tool (CAT).

Science.gov (United States)

Rudolph, E; Färbinger, A; König, J

2012-01-01

The caffeine content of 124 products, including coffee, coffee-based beverages, energy drinks, tea, colas, yoghurt and chocolate, were determined using RP-HPLC with UV detection after solid-phase extraction. Highest concentrations of caffeine were found for coffee prepared from pads (755 mg l⁻¹) and regular filtered coffee (659 mg l⁻¹). The total caffeine content of coffee and chocolate-based beverages was between 15 mg l⁻¹ in chocolate milk and 448 mg l⁻¹ in canned ice coffee. For energy drinks the caffeine content varied in a range from 266 to 340 mg l⁻¹. Caffeine concentrations in tea and ice teas were between 13 and 183 mg l⁻¹. Coffee-flavoured yoghurts ranged from 33 to 48 mg kg⁻¹. The caffeine concentration in chocolate and chocolate bars was between 17 mg kg⁻¹ in whole milk chocolate and 551 mg kg⁻¹ in a chocolate with coffee filling. A caffeine assessment tool was developed and validated by a 3-day dietary record (r²= 0.817, p < 0.01) using these analytical data and caffeine saliva concentrations (r²= 0.427, p < 0.01).

Contributions to total phosphorus intake: all sources considered.

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Calvo, Mona S; Uribarri, Jaime

2013-01-01

High serum phosphorus is linked to poor health outcome and mortality in chronic kidney disease (CKD) patients before or after the initiation of dialysis. Dietary intake of phosphorus, a major determinant of serum phosphorus, seems to be systematically underestimated using the available software tools and generalized nutrient content databases. Several sources of dietary phosphorus including the addition of phosphorus ingredients in food processing, and phosphorus content of vitamin and mineral supplements and commonly used over-the-counter or prescription medications are not fully accounted for by the nutrient content databases and software programs in current clinical use or used in large population studies. In this review, we explore the many unknown sources of phosphorus in the food supply to identify all possible contributors to total phosphorus intake of Americans that have escaped inclusion in past intake estimates. Our goal is to help delineate areas for future interventions that will enable tighter control of dietary phosphorus intake, a critical factor to maintaining health and quality of life in CKD and dialysis patients. © 2012 Wiley Periodicals, Inc.

Total Water Intake from Beverages and Foods Is Associated with Energy Intake and Eating Behaviors in Korean Adults

OpenAIRE

Lee, Kyung Won; Shin, Dayeon; Song, Won O.

2016-01-01

Water is essential for the proper functioning of the body. Even though a recommendation exists for adequate water intake for Koreans, studies identifying actual water intake from all beverages and foods consumed daily in the Korean population are limited. Thus, we estimated total water intake from both beverages and foods and its association with energy intake and eating behaviors in Korean adults. We used a nationally representative sample of 25,122 Korean adults aged ≥19 years, from the Kor...

Total, Dietary, and Supplemental Vitamin C Intake and Risk of Incident Kidney Stones.

Science.gov (United States)

Ferraro, Pietro Manuel; Curhan, Gary C; Gambaro, Giovanni; Taylor, Eric N

2016-03-01

Previous studies of vitamin C and kidney stones were conducted mostly in men and either reported disparate results for supplemental and dietary vitamin C or did not examine dietary vitamin C. Prospective cohort analysis. 156,735 women in the Nurses' Health Study (NHS) I and II and 40,536 men in the Health Professionals Follow-up Study (HPFS). Total, dietary, and supplemental vitamin C intake, adjusted for age, body mass index, thiazide use, and dietary factors. Incident kidney stones. During a median follow-up of 11.3 to 11.7 years, 6,245 incident kidney stones were identified. After multivariable adjustment, total vitamin C intake (vitamin C intake for the 500- to 999-mg/d category was ∼700mg/d. Supplemental vitamin C intake (no use [reference], vitamin C intake was not associated with stones among men or women, although few participants had dietary intakes > 700mg/d. Nutrient intakes derived from food-frequency questionnaires, lack of data on stone composition for all cases. Total and supplemental vitamin C intake was significantly associated with higher risk for incident kidney stones in men, but not in women. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

EFSA NDA Panel (EFSA Panel on Dietetic Products, Nutrition and Allergies), 2015. Scientific Opinion on the safety of caffeine

DEFF Research Database (Denmark)

Tetens, Inge

2015-01-01

Following a request from the European Commission, the EFSA Panel on Dietetic Products, Nutrition and Allergies was asked to deliver a scientific opinion on the safety of caffeine, providing advice on caffeine intakes, from all dietary sources that do not give rise to concerns about adverse health...... not give rise to safety concerns. The same amount does not give rise to safety concerns when consumed .../L of caffeine, taurine and d-glucurono-γ-lactone, respectively), as well as alcohol at doses up to about 0.65 g/kg bw, would not affect the safety of single doses of caffeine up to 200 mg. Habitual caffeine consumption up to 400 mg per day does not give rise to safety concerns for non-pregnant adults. Habitual...

Blood biochemistry, thyroid hormones, and performance in broilers with ascites caused by caffeine.

Science.gov (United States)

Kamely, Mohammad; Karimi Torshizi, Mohammad Amir; Rahimi, Shaban

2016-11-01

Previously, we demonstrated that caffeine, a natural alkaloid, stimulates increased incidences of pulmonary hypertension syndrome (ascites) in broilers. The present study was designed to evaluate the ergogenic effects of caffeine on broiler performance and blood parameters. One-hundred-and-ninety-two Ross 308 male broiler chicks were randomly assigned at one d of age to 16 pens with 4 treatment groups. On d 3, the drinking water was supplemented with caffeine at levels of zero, 12.5, 25, and 50 mg/kg BW/day. Caffeine supplementation linearly improved (P caffeine (P > 0.05). On d 28, increasing caffeine supplementation caused linear reductions in plasma albumin, total protein, globulin, and triglyceride concentrations, and caffeine supplementation increased plasma uric acid concentrations (P caffeine did not consistently affect plasma albumin, globulin, triglyceride, total protein, uric acid, or urea concentrations (P > 0.05), whereas plasma glucose concentrations increased linearly with increasing caffeine levels (P caffeine (P > 0.05), but plasma T 3 concentrations were reduced by caffeine supplementation on d 28 and 42 (P caffeine supplementation on d 42. Skin temperature was not influenced by caffeine supplementation (P > 0.05). There was a negative correlation between thyroid hormone concentrations and BW on d 42 (P caffeine supplementation at the levels of 12.5 to 25 mg/kg BW/day increased BWG, decreased FCR and T 3 , and significantly altered blood biochemistry parameters. © 2016 Poultry Science Association Inc.

Concomitant Effects of Caffeine and Gamma Irradiation in Female Rats

International Nuclear Information System (INIS)

Kafafy, Y. A.

2004-01-01

The present study was undertaken to evaluate the protective potential of caffeine as an antioxidant (80 mg/kg b.w.) i.p. injected 1 hr before exposure to a dose of (7 Gy) gamma irradiation in female rats. Alterations in serum lipids, cholesterol, triacylglycerol and fatty acids as well as total proteins, urea and uric acid have been investigated 1, 3 and 7 days post irradiation and /or caffeine treatment. Histological and histochemical changes of the dorsal aorta have been studied 7 days post treatment. Results revealed elevated total lipids, cholesterol, triacylglycerol, beside distortion in fatty acids throughout the whole experimentation period by caffeine pre injection, irradiation application and by dual treatment. Protein and urea were elevated by caffeine or irradiation, while both treatments dropped their levels, whereas uric was decreased by all treatments. Histopathological changes and deposition of sudanophilic material in the dorsal aorta wall were detected by either one or both treatments, which point out a limitation in the protective potential of caffeine

Association between intake of total vs added sugar on diet quality: a systematic review.

Science.gov (United States)

Louie, Jimmy Chun Yu; Tapsell, Linda C

2015-12-01

Given its potential effect on nutrient and energy density, the sugar content of the diet is a subject of controversy. The aim of this review was to examine the cross-sectional or prospective evidence for associations between the intake of total sugar or added sugar (high vs low intakes) and diet quality or nutrient intakes in the general population. The following databases were searched for English-language articles published between 1972 and 2012: CINAHL Plus, EBM Reviews, ERIC, MEDLINE, PREMEDLINE, PsycINFO, PubMed, and ScienceDirect. The search identified studies that examined the association between intake of total sugar and/or added sugar and diet quality (n = 22) or nutrient intakes (n = 30). The following data were extracted: sample size and population, dietary assessment method, source of added sugar data, source of funding, comparator, association between total sugar or added sugar and diet quality, and the direction and magnitude of the association. Of 22 studies, all except 1 found a higher intake of added sugar to be associated with poorer diet quality, and the exceptional study did not adjust for total energy intake. Twenty-one of 30 studies found a negative association between added sugar and micronutrient intakes. The same association was not found for total sugar intake. Any negative association between dietary sugar and diet quality is better exposed by referring to added sugar rather than total sugar. There was substantial variation in features of study quality, including sample size, so the magnitude of the observed effect was generally small and may not be of clinical significance. Furthermore, the positive influence that core foods such as fruit and milk exert on total sugar values may bias the association between total sugar and diet quality. © The Author(s) 2015. Published by Oxford University Press on behalf of the International Life Sciences Institute. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Effects of caffeine on performance and mood depend on the level of caffeine abstinence.

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Yeomans, Martin R; Ripley, Tamzin; Davies, Laura H; Rusted, Jennifer M; Rogers, Peter J

2002-11-01

Most studies of the effects of caffeine on performance have used regular caffeine consumers who are deprived at test. Thus the reported effects of caffeine could be explained through reversal of caffeine withdrawal. To test how preloading deprived caffeine consumers with 0, 1 or 2 mg/kg caffeine altered the subsequent ability of caffeine to modify mood and performance. Thirty moderate caffeine consumers were given a drink containing 0, 1 or 2 mg/kg caffeine at breakfast followed 60 min later by a second drink containing either 0 or 1 mg/kg caffeine. Performance on a measure of sustained attention and mood were measured before and after each drink. Administration of both 1 and 2 mg/kg caffeine at breakfast decreased reaction time and 1 mg/kg caffeine also increased performance accuracy on the sustained attention (RVIP) task relative to placebo. Both breakfast doses of caffeine also improved rated mental alertness. Similarly, 1 mg/kg caffeine administered 60 min after breakfast decreased reaction time and increased rated mental alertness in the group who had not been given caffeine at breakfast. However, this second dose of caffeine had no effect on subsequent performance or mood in the two groups who had received caffeine at breakfast. Caffeine reliably improved performance on a sustained attention task, and increased rated mental alertness, in moderate caffeine consumers who were tested when caffeine-deprived. However, caffeine had no such effects when consumers were no longer caffeine deprived. These data are consistent with the view that reversal of caffeine withdrawal is a major component of the effects of caffeine on mood and performance.

Favorable effect of moderate dose caffeine on the skeletal system in ovariectomized rats.

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Folwarczna, Joanna; Pytlik, Maria; Zych, Maria; Cegieła, Urszula; Kaczmarczyk-Sedlak, Ilona; Nowińska, Barbara; Sliwiński, Leszek

2013-10-01

Caffeine, a methylxanthine present in coffee, has been postulated to be responsible for an increased risk of osteoporosis in coffee drinkers; however, the data are inconsistent. The aim of the present study was to investigate the effects of a moderate dose of caffeine on the skeletal system of rats with normal and decreased estrogen level (developing osteoporosis due to estrogen deficiency). The experiments were carried out on mature nonovariectomized and ovariectomized Wistar rats, divided into control rats and rats receiving caffeine once daily, 20 mg/kg p.o., for 4 wk. Serum bone turnover markers, bone mass, mass of bone mineral, calcium and phosphorus content, histomorphometric parameters, and bone mechanical properties were examined. Caffeine favorably affected the skeletal system of ovariectomized rats, slightly inhibiting the development of bone changes induced by estrogen deficiency (increasing bone mineralization, and improving the strength and structure of cancellous bone). Moreover, it favorably affected mechanical properties of compact bone. There were no significant effects of caffeine in rats with normal estrogen levels. In conclusion, results of the present study indicate that low-to-moderate caffeine intake may exert some beneficial effects on the skeletal system of mature organisms. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A comparison of the effects of caffeine following abstinence and normal caffeine use.

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Addicott, Merideth A; Laurienti, Paul J

2009-12-01

Caffeine typically produces positive effects on mood and performance. However, tolerance may develop following habitual use, and abrupt cessation can result in withdrawal symptoms, such as fatigue. This study investigated whether caffeine has a greater stimulant effect in a withdrawn state compared to a normal caffeinated state, among moderate daily caffeine consumers. Using a within-subjects design, 17 caffeine consumers (mean +/- sd = 375 +/- 101 mg/day) ingested placebo or caffeine (250 mg) following 30-h of caffeine abstention or normal dietary caffeine use on four separate days. Self-reported mood and performance on choice reaction time, selective attention, and memory tasks were measured. Caffeine had a greater effect on mood and choice reaction time in the abstained state than in the normal caffeinated state, but caffeine improved selective attention and memory in both states. Although improvements in mood and reaction time may best explained as relief from withdrawal symptoms, other performance measures showed no evidence of withdrawal and were equally sensitive to an acute dose of caffeine in the normal caffeinated state.

Caffeine increases anaerobic work and restores cycling performance following a protocol designed to lower endogenous carbohydrate availability.

Directory of Open Access Journals (Sweden)

Marcos David Silva-Cavalcante

Full Text Available The purpose this study was to examine the effects of caffeine ingestion on performance and energy expenditure (anaerobic and aerobic contribution during a 4-km cycling time trial (TT performed after a carbohydrate (CHO availability-lowering exercise protocol. After preliminary and familiarization trials, seven amateur cyclists performed three 4-km cycling TT in a double-blind, randomized and crossover design. The trials were performed either after no previous exercise (CON, or after a CHO availability-lowering exercise protocol (DEP performed in the previous evening, followed by either placebo (DEP-PLA or 5 mg.kg(-1 of caffeine intake (DEP-CAF 1 hour before the trial. Performance was reduced (-2.1% in DEP-PLA vs CON (421.0±12.3 vs 412.4±9.7 s. However, performance was restored in DEP-CAF (404.6±17.1 s compared with DEP-PLA, while no differences were found between DEP-CAF and CON. The anaerobic contribution was increased in DEP-CAF compared with both DEP-PLA and CON (67.4±14.91, 47. 3±14.6 and 55.3±14.0 W, respectively, and this was more pronounced in the first 3 km of the trial. Similarly, total anaerobic work was higher in DEP-CAF than in the other conditions. The integrated electromyographic activity, plasma lactate concentration, oxygen uptake, aerobic contribution and total aerobic work were not different between the conditions. The reduction in performance associated with low CHO availability is reversed with caffeine ingestion due to a higher anaerobic contribution, suggesting that caffeine could access an anaerobic "reserve" that is not used under normal conditions.

Caffeine Increases Anaerobic Work and Restores Cycling Performance following a Protocol Designed to Lower Endogenous Carbohydrate Availability

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Silva-Cavalcante, Marcos David; Correia-Oliveira, Carlos Rafaell; Santos, Ralmony Alcantara; Lopes-Silva, João Paulo; Lima, Hessel Marani; Bertuzzi, Romulo; Duarte, Marcos; Bishop, David John; Lima-Silva, Adriano Eduardo

2013-01-01

The purpose this study was to examine the effects of caffeine ingestion on performance and energy expenditure (anaerobic and aerobic contribution) during a 4-km cycling time trial (TT) performed after a carbohydrate (CHO) availability-lowering exercise protocol. After preliminary and familiarization trials, seven amateur cyclists performed three 4-km cycling TT in a double-blind, randomized and crossover design. The trials were performed either after no previous exercise (CON), or after a CHO availability-lowering exercise protocol (DEP) performed in the previous evening, followed by either placebo (DEP-PLA) or 5 mg.kg−1 of caffeine intake (DEP-CAF) 1 hour before the trial. Performance was reduced (−2.1%) in DEP-PLA vs CON (421.0±12.3 vs 412.4±9.7 s). However, performance was restored in DEP-CAF (404.6±17.1 s) compared with DEP-PLA, while no differences were found between DEP-CAF and CON. The anaerobic contribution was increased in DEP-CAF compared with both DEP-PLA and CON (67.4±14.91, 47. 3±14.6 and 55.3±14.0 W, respectively), and this was more pronounced in the first 3 km of the trial. Similarly, total anaerobic work was higher in DEP-CAF than in the other conditions. The integrated electromyographic activity, plasma lactate concentration, oxygen uptake, aerobic contribution and total aerobic work were not different between the conditions. The reduction in performance associated with low CHO availability is reversed with caffeine ingestion due to a higher anaerobic contribution, suggesting that caffeine could access an anaerobic “reserve” that is not used under normal conditions. PMID:23977198

A caffeine-maltodextrin mouth rinse counters mental fatigue.

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Van Cutsem, Jeroen; De Pauw, Kevin; Marcora, Samuele; Meeusen, Romain; Roelands, Bart

2018-04-01

Mental fatigue is a psychobiological state caused by prolonged periods of demanding cognitive activity that has negative implications on many aspects in daily life. Caffeine and carbohydrate ingestion have been shown to be able to reduce these negative effects of mental fatigue. Intake of these substances might however be less desirable in some situations (e.g., restricted caloric intake, Ramadan). Rinsing caffeine or glucose within the mouth has already been shown to improve exercise performance. Therefore, we sought to evaluate the effect of frequent caffeine-maltodextrin (CAF-MALT) mouth rinsing on mental fatigue induced by a prolonged cognitive task. Ten males (age 23 ± 2 years, physical activity 7.3 ± 4.3 h/week, low CAF users) performed two trials. Participants first completed a Flanker task (3 min), then performed a 90-min mentally fatiguing task (Stroop task), followed by another Flanker task. Before the start and after each 12.5% of the Stroop task (eight blocks), subjects received a CAF-MALT mouth rinse (MR: 0.3 g/25 ml CAF: 1.6g/25 ml MALT) or placebo (PLAC: 25 ml artificial saliva). Self-reported mental fatigue was lower in MR (p = 0.017) compared to PLAC. Normalized accuracy (accuracy first block = 100%) was higher in the last block of the Stroop in MR (p = 0.032) compared to PLAC. P2 amplitude in the dorsolateral prefrontal cortex (DLPFC) decreased over time only in PLAC (p = 0.017). Frequent mouth rinsing during a prolonged and demanding cognitive task reduces mental fatigue compared to mouth rinsing with artificial saliva.

Caffeine intake and pregnancy outcomes: a meta-analytic review Consumo de cafeína na gravidez e desfechos perinatais

Directory of Open Access Journals (Sweden)

Iná S. Santos

1998-07-01

Full Text Available Epidemiological publications on the relationship of caffeine to birth weight and duration of human pregnancy, from 1966 to 1995, were searched through Medline. Each study was treated as the stratification variable, and its weight in the weighted average was proportional to the inverse of its variance. Twenty-six studies were located. Among the twenty-two studies on birth weight, eleven were on mean birth weight, nine on low birth weight (LBW, and four on intrauterine growth retardation (IUGR. Combined analysis of mean birth weigh study results showed a significant decrease in birth weight of nearly 43g among newborns of the heaviest caffeine-consuming mothers. LBW, IUGR, and preterm delivery displayed significant homogeneity in the test results, indicating that a pooled estimate should not be taken as an adequate measure. The high heterogeneity of the available literature on the effects of caffeine on LBW, IUGR, and preterm delivery prevents estimation of reliable pooled estimates through meta-analysis. Further assessment of caffeine intake during pregnancy is needed in future research.Foram rastreadas as publicações epidemiológicas de 1966 a 1995 sobre a associação entre cafeína e peso ao nascer e duração da gestação humana através de pesquisa em Medline. Cada estudo foi tratado como uma categoria de uma variável e seu peso foi proporcional ao inverso de sua variância. Foram localizados vinte e seis estudos. Entre os vinte e dois estudos sobre peso ao nascer, onze foram sobre peso médio ao nascer, nove sobre baixo peso ao nascer (BPN e quatro sobre retardo do crescimento intra-uterino (RCIU. O efeito agregado sobre o peso médio ao nascer mostrou uma redução estatisticamente significativa de 43 gramas entre os recém-nascidos de mães que consumiam maiores quantidades de cafeína. A análise agregada do efeito sobre BPN, RCIU e nascimentos pré-termos apresentou teste de homegeneidade estatisticamente significativo, indicando

Effects of caffeine on circadian phase, amplitude and period evaluated in cells in vitro and peripheral organs in vivo in PER2::LUCIFERASE mice

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Narishige, Seira; Kuwahara, Mari; Shinozaki, Ayako; Okada, Satoshi; Ikeda, Yuko; Kamagata, Mayo; Tahara, Yu; Shibata, Shigenobu

2014-01-01

Background and Purpose Caffeine is one of the most commonly used psychoactive substances. Circadian rhythms consist of the main suprachiasmatic nucleus (SCN) clocks and peripheral clocks. Although caffeine lengthens circadian rhythms and modifies phase changes in SCN-operated rhythms, the effects on caffeine on the phase, period and amplitude of peripheral organ clocks are not known. In addition, the role of cAMP/Ca2+ signalling in effects of caffeine on rhythm has not been fully elucidated. Experimental Approach We examined whether chronic or transient application of caffeine affects circadian period/amplitude and phase by evaluating bioluminescence rhythm in PER2::LUCIFERASE knock-in mice. Circadian rhythms were monitored in vitro using fibroblasts and ex vivo and in vivo for monitoring of peripheral clocks. Key Results Chronic application of caffeine (0.1–10 mM) increased period and amplitude in vitro. Transient application of caffeine (10 mM) near the bottom of the decreasing phase of bioluminescence rhythm caused phase advance in vitro. Caffeine (0.1%) intake caused a phase delay under light–dark or constant dark conditions, suggesting a period-lengthening effect in vivo. Caffeine (20 mg·kg−1) at daytime or at late night-time caused phase advance or delay in bioluminescence rhythm in the liver and kidney respectively. The complicated roles of cAMP/Ca2+ signalling may be involved in the caffeine-induced increase of period and amplitude in vitro. Conclusions and Implications Caffeine affects circadian rhythm in mice by lengthening the period and causing a phase shift of peripheral clocks. These results suggest that caffeine intake with food/drink may help with food-induced resetting of peripheral circadian clocks. PMID:25160990

Biodegradation of Caffeine by Trichosporon asahii Isolated from Caffeine Contaminated Soil

OpenAIRE

LAKSHMI V.; NILANJANA DAS

2011-01-01

Studies were carried out on caffeine degradation using Trichosporon asahii, a yeast species isolated from caffeine contaminated soil. There was 100 % degradation of caffeine at 54 h by the yeast cells acclimated to the medium containing caffeine and sucrose both. Experiments with T. asahii growing on caffeine in the presenceof 1 mM 1-aminobenzotriazole (ABT), an inhibitor of the cytochrome P-450 enzyme system, resulted inhibition of biomass production relative to positive control implicating ...

Caffeine Content in Popular Energy Drinks and Energy Shots.

Science.gov (United States)

Attipoe, Selasi; Leggit, Jeffrey; Deuster, Patricia A

2016-09-01

The use of energy beverages is high among the general population and military personnel. Previous studies have reported discrepancies between the actual amount of caffeine in products and the amount of caffeine on stated labels. Thus, the purpose of this study was to examine the content of caffeine listed on the labels of various energy drinks and energy shots. Top-selling energy drinks (n = 9) and energy shots (n = 5) were purchased from retail stores. Three of each of the 14 products were purchased and analyzed for caffeine content by an independent laboratory. Of the 14 products tested, 5 did not provide caffeine amounts on their facts panel-of those, 3 listed caffeine as an ingredient and 2 listed caffeine as part of a proprietary blend. The remaining 9 (of 14) products stated the amounts of caffeine on their labels, all of which were within 15% of the amount indicated on the label. In this study, although the energy beverages that indicated the amount of caffeine it contained had values within ±15% of the amount listed on the label, a potentially acceptable range, this finding is not acceptable with regard to current labeling regulations, which require added ingredients to total 100%. Reprint & Copyright © 2016 Association of Military Surgeons of the U.S.

Caffeine and Insomnia in People Living With HIV From the Miami Adult Studies on HIV (MASH) Cohort.

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Ramamoorthy, Venkataraghavan; Campa, Adriana; Rubens, Muni; Martinez, Sabrina S; Fleetwood, Christina; Stewart, Tiffanie; Liuzzi, Juan P; George, Florence; Khan, Hafiz; Li, Yinghui; Baum, Marianna K

We explored the relationship between caffeine consumption, insomnia, and HIV disease progression (CD4+ T cell counts and HIV viral loads). Caffeine intake and insomnia levels were measured using the Modified Caffeine Consumption Questionnaire and the Pittsburgh Insomnia Rating Scale (PIRS) in 130 clinically stable participants who were living with HIV, taking antiretroviral therapy, and recruited from the Miami Adult Studies on HIV cohort. Linear regressions showed that caffeine consumption was significantly and adversely associated with distress score, quality-of-life score, and global PIRS score. Linear regression analyses also showed that global PIRS score was significantly associated with lower CD4+ T cell counts and higher HIV viral loads. Caffeine could have precipitated insomnia in susceptible people living with HIV, which could be detrimental to their disease progression states. Copyright © 2017 Association of Nurses in AIDS Care. Published by Elsevier Inc. All rights reserved.

Energy drink consumption and impact on caffeine risk.

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Thomson, Barbara M; Campbell, Donald M; Cressey, Peter; Egan, Ursula; Horn, Beverley

2014-01-01

The impact of caffeine from energy drinks occurs against a background exposure from naturally occurring caffeine (coffee, tea, cocoa and foods containing these ingredients) and caffeinated beverages (kola-type soft drinks). Background caffeine exposure, excluding energy drinks, was assessed for six New Zealand population groups aged 15 years and over (n = 4503) by combining concentration data for 53 caffeine-containing foods with consumption information from the 2008/09 New Zealand Adult Nutrition Survey (ANS). Caffeine exposure for those who consumed energy drinks (n = 138) was similarly assessed, with inclusion of energy drinks. Forty-seven energy drink products were identified on the New Zealand market in 2010. Product volumes ranged from 30 to 600 ml per unit, resulting in exposures of 10-300 mg caffeine per retail unit consumed. A small percentage, 3.1%, of New Zealanders reported consuming energy drinks, with most energy drink consumers (110/138) drinking one serving per 24 h. The maximum number of energy drinks consumed per 24 h was 14 (total caffeine of 390 mg). A high degree of brand loyalty was evident. Since only a minor proportion of New Zealanders reported consuming energy drinks, a greater number of New Zealanders exceeded a potentially adverse effect level (AEL) of 3 mg kg(-1) bw day(-1) for caffeine from caffeine-containing foods than from energy drinks. Energy drink consumption is not a risk at a population level because of the low prevalence of consumption. At an individual level, however, teenagers, adults (20-64 years) and females (16-44 years) were more likely to exceed the AEL by consuming energy drinks in combination with caffeine-containing foods.

Effects of coffee/caffeine on brain health and disease: What should I tell my patients?

Science.gov (United States)

Nehlig, Astrid

2016-04-01

Over the last decade, Food Regulation Authorities have concluded that coffee/caffeine consumption is not harmful if consumed at levels of 200 mg in one sitting (around 2½ cups of coffee) or 400 mg daily (around 5 cups of coffee). In addition, caffeine has many positive actions on the brain. It can increase alertness and well-being, help concentration, improve mood and limit depression. Caffeine may disturb sleep, but only in sensitive individuals. It may raise anxiety in a small subset of particularly sensitive people. Caffeine does not seem to lead to dependence, although a minority of people experience withdrawal symptoms. Caffeine can potentiate the effect of regular analgesic drugs in headache and migraine. Lifelong coffee/caffeine consumption has been associated with prevention of cognitive decline, and reduced risk of developing stroke, Parkinson's disease and Alzheimer's disease. Its consumption does not seem to influence seizure occurrence. Thus, daily coffee and caffeine intake can be part of a healthy balanced diet; its consumption does not need to be stopped in elderly people. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Chronic caffeine consumption prevents memory disturbance in different animal models of memory decline.

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Cunha, Rodrigo A; Agostinho, Paula M

2010-01-01

Caffeine, the most widely consumed psychoactive drug, enhances attention/vigilance, stabilizes mood, and might also independently enhance cognitive performance. Notably, caffeine displays clearer and more robust beneficial effects on memory performance when memory is perturbed by stressful or noxious stimuli either in human or animal studies. Thus, caffeine restores memory performance in sleep-deprived or aged human individuals, a finding replicated in rodent animal models. Likewise, in animal models of Alzheimer's disease (AD), caffeine alleviates memory dysfunction, which is in accordance with the tentative inverse correlation between caffeine intake and the incidence of AD in different (but not all) cohorts. Caffeine also affords beneficial effects in animal models of conditions expected to impair memory performance such as Parkinson's disease, chronic stress, type 2 diabetes, attention deficit and hyperactivity disorder, early life convulsions, or alcohol-induced amnesia. Thus, caffeine should not be viewed as a cognitive enhancer but instead as a cognitive normalizer. Interestingly, these beneficial effects of caffeine on stress-induced memory disturbance are mimicked by antagonists of adenosine A2A receptors. This prominent role of A2A receptors in preventing memory deterioration is probably related to the synaptic localization of this receptor in limbic areas and its ability to control glutamatergic transmission, especially NMDA receptor-dependent plasticity, and to control apoptosis, brain metabolism, and the burden of neuroinflammation. This opens the real and exciting possibility that caffeine consumption might be a prophylactic strategy and A2A receptor antagonists may be a novel therapeutic option to manage memory dysfunction both in AD and in other chronic neurodegenerative disorders where memory deficits occur.

Caffeine controversies.

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Gentle, Samuel J; Travers, Colm P; Carlo, Waldemar A

2018-04-01

Caffeine use in preterm infants has endured several paradigms: from standard of care to possible neurotoxin to one of the few medications for which there is evidence of bronchopulmonary dysplasia (BPD) risk reduction. The purpose of the review is to analyze this dynamic trajectory and discuss controversies that still remain after decades of caffeine use. Following concerns for caffeine safety in preterm infants, a large randomized controlled trial demonstrated a reduction in BPD and treatment for patent ductus arteriosus. The lower rate of death or neurodevelopmental impairment noted at 18-21 months was not statistically different at later timepoints; however, infants in the caffeine group had lower rates of motor impairment at 11-year follow-up. The time of caffeine therapy initiation is now substantially earlier, and doses used are sometimes higher that previously used, but there are limited data to support these practices. Caffeine therapy for apnea of prematurity (AOP) remains one of the pillars of neonatal care, although more evidence to support dosing and timing of initiation and discontinuation are needed.

Caffeine Citrate Dosing Adjustments to Assure Stable Caffeine Concentrations in Preterm Neonates.

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Koch, Gilbert; Datta, Alexandre N; Jost, Kerstin; Schulzke, Sven M; van den Anker, John; Pfister, Marc

2017-12-01

To identify dosing strategies that will assure stable caffeine concentrations in preterm neonates despite changing caffeine clearance during the first 8 weeks of life. A 3-step simulation approach was used to compute caffeine doses that would achieve stable caffeine concentrations in the first 8 weeks after birth: (1) a mathematical weight change model was developed based on published weight distribution data; (2) a pharmacokinetic model was developed based on published models that accounts for individual body weight, postnatal, and gestational age on caffeine clearance and volume of distribution; and (3) caffeine concentrations were simulated for different dosing regimens. A standard dosing regimen of caffeine citrate (using a 20 mg/kg loading dose and 5 mg/kg/day maintenance dose) is associated with a maximal trough caffeine concentration of 15 mg/L after 1 week of treatment. However, trough concentrations subsequently exhibit a clinically relevant decrease because of increasing clearance. Model-based simulations indicate that an adjusted maintenance dose of 6 mg/kg/day in the second week, 7 mg/kg/day in the third to fourth week and 8 mg/kg/day in the fifth to eighth week assures stable caffeine concentrations with a target trough concentration of 15 mg/L. To assure stable caffeine concentrations during the first 8 weeks of life, the caffeine citrate maintenance dose needs to be increased by 1 mg/kg every 1-2 weeks. These simple adjustments are expected to maintain exposure to stable caffeine concentrations throughout this important developmental period and might enhance both the short- and long-term beneficial effects of caffeine treatment. Copyright © 2017 Elsevier Inc. All rights reserved.

Total and partial sleep deprivation: Effects on plasma TNF-αRI, TNF-αRII, and IL-6, and reversal by caffeine operating through adenosine A2 receptor

Science.gov (United States)

Shearer, William T.; Reuben, James M.; Lee, Bang-Ning; Mullington, Janet; Price, Nicholas; Dinges, David F.

2000-01-01

Plasma levels of IL-6 and TNF-α are elevated in individuals who are deprived of sleep. TNF-α regulates expression of its soluble receptors, sTNF-αRI and sTNF-αRII. Sleep deprivation (SD) also increases extracellular adenosine that induces sedation and sleep. An antagonist of adenosine, caffeine, raises exogenous adenosine levels, stimulates the expression of IL-6 and inhibits the release of TNF-α. Our objective was to determine the effect of total SD (TSD) or partial SD (PSD) on the levels of these sleep regulatory molecules in volunteers who experienced SD with or without the consumption of caffeine. Plasma levels of IL-6, sTNF-αRI and sTNF-αRII were assayed by ELISA in samples collected at 90-min intervals from each subject over an 88-hour period. The results were analyzed by the repeated measures ANOVA. Whereas only TSD significantly increased sTNF-αRI over time, caffeine suppressed both sTNF-α receptors in TSD and PSD subjects. The selective increase in the expression of sTNF-αRI and not sTNF-αRII in subjects experiencing TSD with caffeine compared with others experiencing PSD with caffeine has not been previously reported. Moreover, caffeine significantly increased IL-6 in TSD subjects compared with those who did not receive caffeine. However, subjects who were permitted intermittent naps (PSD) ablated the effects of caffeine and reduced their level of IL-6 to that of the TSD group. These data further lend support to the hypothesis that the sTNF-αRI and not the sTNF-αRII plays a significant role in sleep regulation by TNF-α. .

[Caffeine: traditional and new therapeutic indications and use as a dermatological model drug].

Science.gov (United States)

Bors, Luca; Bajza, Ágnes; Kocsis, Dorottya; Erdő, Franciska

2018-03-01

Coffee consumption had already been described in the 15th century. The spreading of coffee drinking was not only a consequence of its delicious aromatic taste, but also of its pharmacological effects, especially due to its caffeine content. In this review, the mechanisms behind its complex stimulatory effects and the latest studies on the possible new therapeutic indications of caffeine are summarized. Several papers reported the neuroprotective (in Alzheimer's and Parkinson's disease) and hepatoprotective profiles of caffeine, and we show the most promising new results about its preventive properties in dermal malignancies. These findings were described both in cell cultures and in vivo. The application of caffeine and coffee in cosmetology and dermatological products is based on their antioxidant property and on the above-mentioned beneficial effects. Caffeine is also presented here as a dermatological model drug due to its hydrophilic profile. It can be used for designing and comparing different novel drug formulations, although beside the transcellular route, the follicular and transappendageal pathways play also important roles in its skin penetration. Taken together, caffeine molecule has many recently discovered beneficial pharmacological effects, but one should be careful with its excessive consumption. It can result in several adverse events if overdosed and in case of regular intake of high doses, after abandonment, withdrawal symptoms may appear. Orv Hetil. 2018; 159(10): 384-390.

Caffeine challenge test and panic disorder: a systematic literature review.

Science.gov (United States)

Vilarim, Marina Machado; Rocha Araujo, Daniele Marano; Nardi, Antonio Egidio

2011-08-01

This systematic review aimed to examine the results of studies that have investigated the induction of panic attacks and/or the anxiogenic effect of the caffeine challenge test in patients with panic disorder. The literature search was performed in PubMed, Biblioteca Virtual em Saúde and the ISI Web of Knowledge. The words used for the search were caffeine, caffeine challenge test, panic disorder, panic attacks and anxiety disorder. In total, we selected eight randomized, double-blind studies where caffeine was administered orally, and none of them controlled for confounding factors in the analysis. The percentage of loss during follow-up ranged between 14.3% and 73.1%. The eight studies all showed a positive association between caffeine and anxiogenic effects and/or panic disorder.

The effect of caffeine as an ergogenic aid in anaerobic exercise.

Science.gov (United States)

Woolf, Kathleen; Bidwell, Wendy K; Carlson, Amanda G

2008-08-01

The study examined caffeine (5 mg/kg body weight) vs. placebo during anaerobic exercise. Eighteen male athletes (24.1+/-5.8 yr; BMI 26.4+/-2.2 kg/m2) completed a leg press, chest press, and Wingate test. During the caffeine trial, more total weight was lifted with the chest press, and a greater peak power was obtained during the Wingate test. No differences were observed between treatments for the leg press and average power, minimum power, and power drop (Wingate test). There was a significant treatment main effect found for postexercise glucose and insulin concentrations; higher concentrations were found in the caffeine trial. A significant interaction effect (treatment and time) was found for cortisol and glucose concentrations; both increased with caffeine and decreased with placebo. Postexercise systolic blood pressure was significantly higher during the caffeine trial. No differences were found between treatments for serum free-fatty-acid concentrations, plasma lactate concentrations, serum cortisol concentrations, heart rate, and rating of perceived exertion. Thus, a moderate dose of caffeine resulted in more total weight lifted for the chest press and a greater peak power attained during the Wingate test in competitive athletes.

Chronic coffee and caffeine ingestion effects on the cognitive function and antioxidant system of rat brains.

Science.gov (United States)

Abreu, Renata Viana; Silva-Oliveira, Eliane Moretto; Moraes, Márcio Flávio Dutra; Pereira, Grace Schenatto; Moraes-Santos, Tasso

2011-10-01

Coffee is a popular beverage consumed worldwide and its effect on health protection has been well studied throughout literature. This study investigates the effect of chronic coffee and caffeine ingestion on cognitive behavior and the antioxidant system of rat brains. The paradigms of open field and object recognition were used to assess locomotor and exploratory activities, as well as learning and memory. The antioxidant system was evaluated by determining the activities of glutathione reductase (GR), glutathione peroxidase (GPx) and superoxide dismutase (SOD), as well as the lipid peroxidation and reduced glutathione content. Five groups of male rats were fed for approximately 80 days with different diets: control diet (CD), fed a control diet; 3% coffee diet (3%Co) and 6% coffee diet (6%Co), both fed a diet containing brewed coffee; 0.04% caffeine diet (0.04%Ca) and 0.08% caffeine diet (0.08%Ca), both fed a control diet supplemented with caffeine. The estimated caffeine intake was approximately 20 and 40 mg/kg per day, for the 3%Co-0.04%Ca and 6%Co-0.08%Ca treatments, respectively. At 90 days of life, the animals were subjected to the behavioral tasks and then sacrificed. The results indicated that the intake of coffee, similar to caffeine, improved long-term memory when tested with object recognition; however, this was not accompanied by an increase in locomotor and exploratory activities. In addition, chronic coffee and caffeine ingestion reduced the lipid peroxidation of brain membranes and increased the concentration of reduced-glutathione. The activities of the GR and SOD were similarly increased, but no change in GPx activity could be observed. Thus, besides improving cognitive function, our data show that chronic coffee consumption modulates the endogenous antioxidant system in the brain. Therefore, chronic coffee ingestion, through the protection of the antioxidant system, may play an important role in preventing age-associated decline in the cognitive

Acute personalized habitual caffeine doses improve attention and have selective effects when considering the fractionation of executive functions.

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Lanini, Juliana; Galduróz, José Carlos Fernandes; Pompéia, Sabine

2016-01-01

Caffeine is widely used, often consumed with food, and improves simple and complex/executive attention under fasting conditions. We investigated whether these cognitive effects are observed when personalized habitual doses of caffeine are ingested by caffeine consumers, whether they are influenced by nutriments and if various executive domains are susceptible to improvement. This was a double-blind, placebo-controlled study including 60 young, healthy, rested males randomly assigned to one of four treatments: placebo fasting, caffeine fasting, placebo meal and caffeine meal. Caffeine doses were individualized for each participant based on their self-reported caffeine consumption at the time of testing (morning). The test battery included measures of simple and sustained attention, executive domains (inhibiting, updating, shifting, dual tasking, planning and accessing long-term memory), control measures of subjective alterations, glucose and insulin levels, skin conductance, heart rate and pupil dilation. Regardless of meal intake, acute habitual doses of caffeine decreased fatigue, and improved simple and sustained attention and executive updating. This executive effect was not secondary to the habitual weekly dose consumed, changes in simple and sustained attention, mood, meal ingestion and increases in cognitive effort. We conclude that the morning caffeine "fix" has positive attentional effects and selectively improved executive updating whether or not caffeine is consumed with food. Copyright © 2015 John Wiley & Sons, Ltd.

Caffeine-based food supplements and beverages: Trends of consumption for performance purposes and safety concerns.

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Bessada, Sílvia M F; Alves, Rita C; Oliveira, M Beatriz P P

2018-07-01

Nowadays, daily food supplementation regarding the improvement of physical and mental performance is a growing trend in sport practitioners, young students and active people. Food supplements are foodstuffs, labeled under food law and not obliged to safety assessments before their commercialization. Several products are commercialized claiming ergogenic effects as marketing strategies. Caffeine is often one of their main ingredients, as it increases both physical performance and concentration. This manuscript presents a general overview of the current caffeine-based food supplements and energy drinks available in the Portuguese market, as well as the consuming trends regarding their ergogenic effects, performance purposes, and active ingredients. Product claims, recommended daily intakes, caffeine pharmacology, and safety concerns aspects are also discussed aspects. Copyright © 2018 Elsevier Ltd. All rights reserved.

Attentional bias for caffeine-related stimuli in high but not moderate or non-caffeine consumers.

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Yeomans, Martin R; Javaherian, Shabnam; Tovey, Heather M; Stafford, Lorenzo D

2005-09-01

Attentional bias for drug-related cues has been reported with a wide range of drugs, but to date the extent to which caffeine consumers show similar biases for caffeine-related stimuli has not been tested. The present study therefore examined this issue in terms of differences in attentional bias for caffeine-related words in High, Moderate and Non-caffeine consumers using a dot-probe word task following overnight caffeine abstinence. This study was conducted to test whether caffeine consumers show an attentional bias for caffeine-related words, and whether such biases relate to habitual levels of caffeine use. Sixteen High, Moderate and Non-consumers of caffeine were asked to complete a modified dot-probe task in order to measure attentional bias for caffeine-related relative to neutral control word groups. The task was completed following overnight caffeine abstinence, and participants also completed mood and caffeine-craving measures. The High consumer group showed a significant attentional bias for the caffeine-related words, but no such bias was seen in Moderate or Non-consumer groups. As expected, craving for caffeine was strongest in the High consumers and weakest in the Non-consumers. Attentional bias in the High group correlated with self-reported caffeine consumption and with craving for caffeine, but neither effect was significant in the Moderate group. These data confirm that High caffeine consumers show attentional bias for caffeine-related stimuli, consistent with current theories of drug addiction.

Caffeine in the diet

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Diet - caffeine ... Caffeine is absorbed and passes quickly into the brain. It does not collect in the bloodstream or ... been consumed. There is no nutritional need for caffeine. It can be avoided in the diet. Caffeine ...

Acute effects of theanine, caffeine and theanine-caffeine combination on attention.

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Kahathuduwa, Chanaka N; Dassanayake, Tharaka L; Amarakoon, A M Tissa; Weerasinghe, Vajira S

2017-07-01

l-theanine is a constituent of tea which is claimed to enhance cognitive functions. We aimed to determine whether theanine and theanine-caffeine combination have acute positive effects on cognitive and neurophysiological measures of attention, compared to caffeine (a positive control) and a placebo in healthy individuals. In a placebo-controlled, five-way crossover trial in 20 healthy male volunteers, we compared the effects of l-theanine (200 mg), caffeine (160 mg), their combination, black tea (one cup) and a placebo (distilled water) on cognitive (simple [SVRT] and recognition visual reaction time [RVRT]) and neurophysiological (event-related potentials [ERPs]) measures of attention. We also recorded visual (VEPs) and motor evoked potentials (MEPs) to examine any effects of treatments on peripheral visual and motor conduction, respectively. Mean RVRT was significantly improved by theanine (P = 0.019), caffeine (P = 0.043), and theanine-caffeine combination (P = 0.001), but not by tea (P = 0.429) or placebo (P = 0.822). VEP or MEP latencies or SVRT did not show significant inter-treatment differences. Theanine (P = 0.001) and caffeine (P = 0.001) elicited significantly larger mean peak-to-peak N2-P300 ERP amplitudes than the placebo, whereas theanine-caffeine combination elicited a significantly larger mean N2-P300 amplitude than placebo (P caffeine (P = 0.005). No significant theanine × caffeine interaction was observed for RVRT or N2-P300 amplitude. A dose of theanine equivalent of eight cups of back tea improves cognitive and neurophysiological measures of selective attention, to a degree that is comparable with that of caffeine. Theanine and caffeine seem to have additive effects on attention in high doses.

Effects of chronic administration of caffeine and stress on feeding behavior of rats.

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Pettenuzzo, Leticia Ferreira; Noschang, Cristie; von Pozzer Toigo, Eduardo; Fachin, Andrelisa; Vendite, Deusa; Dalmaz, Carla

2008-10-20

Anorectic effects of caffeine are controversial in the literature, while stress and obesity are growing problems in our society. Since many stressed people are coffee drinkers, the objective of the present study was to evaluate the effect of stress and chronic administration of caffeine on feeding behavior and body weight in male and female rats. Wistar rats (both males and females) were divided into 3 groups: control (receiving water), caffeine 0.3 g/L and caffeine 1.0 g/L (in the drinking water). These groups were subdivided into non-stressed and stressed (repeated-restraint stress for 40 days). During the entire treatment, chow consumption was monitored and rats were weighed monthly. Afterwards, feeding behavior was evaluated during 3-min trials in food-deprived and ad libitum fed animals and also in repeated exposures, using palatable food (Froot Loops and Cheetos). Chronic administration of caffeine did not affect rat chow consumption or body weight gain, but diminished the consumption of both salty (Cheetos) and sweet (Froot Loops) palatable food. In the repeated trial tests, stress diminished savory snack consumption in the later exposures [I.S. Racotta, J. Leblanc, D. Richard The effect of caffeine on food intake in rats: involvement of corticotropin-releasing factor and the sympatho-adrenal system. Pharmacol Biochem Behav. 1994, 48:887-892; S.D. Comer, M. Haney, R.W. Foltin, M.W. Fischman Effects of caffeine withdrawal on humans living in a residential laboratory. Exp Clin Psychopharmacol. 1997, 5:399-403; A. Jessen, B. Buemann, S. Toubro, I.M. Skovgaard, A. Astrup The appetite-suppressant effect of nicotine is enhanced by caffeine. Diab Ob Metab. 2005, 7:327-333; J.M. Carney Effects of caffeine, theophylline and theobromine on scheduled controlled responding in rats. Br J Pharmacol. 1982, 75:451-454] and caffeine diminished consumption of both palatable foods (savory and sweet) during the early and later exposures. Most responses to caffeine were stronger

Caffeine decreases phospho-Chk1 (Ser317) and increases mitotic cells with cyclin B1 and caspase 3 in tumors from UVB-treated mice.

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Lu, Yao-Ping; Lou, You-Rong; Peng, Qing-Yun; Nghiem, Paul; Conney, Allan H

2011-07-01

Oral administration of caffeine to mice inhibits UVB-induced carcinogenesis, and these results are paralleled by epidemiology studies indicating that caffeinated coffee and tea intake (but not decaffeinated beverage intake) is associated with decreased incidence of nonmelanoma skin cancer. Topical applications of caffeine to the skin of SKH-1 mice that had previously been treated with UVB inhibited subsequent skin tumor development and stimulated apoptosis in tumors but not in nontumor areas of the epidermis. This study sought to determine the basis of these differential effects on tumor versus nontumor sites that can be induced by caffeine, long after all UVB treatment has ceased. The activation status of the ATR/Chk1 pathway in UVB-induced tumors and uninvolved skin was determined by quantitating phospho-Chk1 (Ser317) and induction of lethal mitosis in vivo in the presence and absence of topical caffeine treatment. In the absence of caffeine, we found that UVB-induced tumors often had islands of phospho-Chk1 (Ser317) staining cells that were not present in nontumor areas of the epidermis. Treatment of mice with topical caffeine significantly diminished phospho-Chk1 (Ser317) staining and increased the number of mitotic cells that expressed cyclin B1 and caspase 3 in tumors, consistent with caffeine-induced lethal mitosis selectively in tumors. We hypothesize that compared with adjacent uninvolved skin, UVB-induced skin tumors have elevated activation of, and dependence on, the ATR/Chk1 pathway long after UVB exposure has ceased and that caffeine can induce apoptosis selectively in tumors by inhibiting this pathway and promoting lethal mitosis.

Caffeine consumption and exacerbations of chronic obstructive pulmonary disease: Retrospective study

Directory of Open Access Journals (Sweden)

P.O. Lopes

2015-09-01

Full Text Available Background: The modulation of adenosine receptors has been proposed as new therapeutic target for chronic obstructive pulmonary disease, but studies in humans were negative. Caffeine is widely consumed and acts by non-selective modulation of these receptors, allowing for a non-interventional evaluation of the purinergic effects on COPD. We evaluated the effects of chronic caffeine consumption on the risk for COPD exacerbations. Methods: Retrospective study including patients with COPD. The total number of exacerbations during a three-year period and the mean daily caffeine consumption in the last twenty years were evaluated. A univariate and multiple regression analysis were performed for evaluation of the significant predictors of exacerbations. Results: A total of 90 patients were included. Most were males (82.2% and had a mean forced expiratory volume in the first second (FEV1 of 57.0 ± 17.1% predicted. The mean daily caffeine consumption was 149.7 ± 140.9 mg. There was no correlation between the mean caffeine consumption and exacerbations (p > 0.05. Discussion: Our results suggest that caffeine has no significant effect on the frequency of COPD exacerbations. These conclusions are limited by the sample size and the retrospective nature of the study. Keywords: COPD, Caffeine, Disease exacerbation, Purines, Pharmacology, Coffee, Respiratory Tract Diseases

Effect of Coffee and Caffeine Ingestion on Resistance Exercise Performance.

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Richardson, Darren L; Clarke, Neil D

2016-10-01

Richardson, DL and Clarke, ND. Effect of coffee and caffeine ingestion on resistance exercise performance. J Strength Cond Res 30(10): 2892-2900, 2016-The aim of the present study was to determine the effect of ingesting caffeine dose-matched anhydrous caffeine, coffee, or decaffeinated coffee plus anhydrous caffeine during resistance exercise on performance. Nine resistance-trained men (mean ± SD: age, 24 ± 2 years; weight, 84 ± 8 kg; height, 180 ± 8 cm) completed a squat and bench press exercise protocol at 60% 1 repetition maximum until failure on 5 occasions consuming 0.15 g·kg caffeinated coffee (COF), 0.15 g·kg decaffeinated coffee (DEC), 0.15 g·kg decaffeinated coffee plus 5 mg·kg anhydrous caffeine (D + C), 5 mg·kg anhydrous caffeine (CAF), or a placebo (PLA). Felt arousal and rating of perceived exertion (RPE) were used to assess perceptual variables and heart rate (HR) to assess physiological responses between trials. There were significant differences in total weight lifted for the squat between conditions (p caffeine have the ability to improve performance during a resistance exercise protocol, although possibly not over multiple bouts.

Caffeine and Your Child

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... Staying Safe Videos for Educators Search English Español Caffeine KidsHealth / For Parents / Caffeine What's in this article? ... español La cafeína y su hijo What Is Caffeine? Caffeine is a natural stimulant found in coffee, ...

Naturalistic Effects of Five Days of Bedtime Caffeine Use on Sleep, Next-Day Cognitive Performance, and Mood

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Tiplady, Brian; Priestley, Caroline M.; Rogers, Peter J.

2014-01-01

Background: Disruptive effects of caffeine on sleep have previously been reported, although measures of next-day mood and performance have rarely been included. The present study aims to evaluate the effects of caffeine on sleep and associated next-day effects in a naturalistic field setting. Methods: Nineteen participants (daily caffeine intake 0–141 mg), assessed as good sleepers, took part in a randomized, placebo-controlled, double-blind, 2-week crossover study to assess the effects of bedtime caffeine use (250 mg) on sleep and next-day cognitive performance and mood, which were assessed on a mobile phone in the morning and afternoon. Sleep was assessed objectively (actiwatch) and subjectively (sleep diary). Results: Caffeine's effects on sleep were largely restricted to the first day of administration, with actigraphically measured reduced sleep efficiency, increased activity score and fragmentation index, decreased self-rated sleep quality, and an increased occurrence of participants waking early; only decreased sleep efficiency remained over the week. Effects on next-day performance and mood were evident over the whole week, although despite disrupting sleep, accuracy on a working memory task was higher after caffeine than placebo administration. Conclusions: Caffeine disrupted sleep, although when assessing next-day performance, which may have been affected by the presence of residual caffeine, performance appeared better after caffeine compared to placebo, although this was most likely due to prevention of the effects of overnight withdrawal from caffeine rather than representing a net benefit. Furthermore, partial tolerance developed to the effects of caffeine on sleep. PMID:24868491

Estimated Intakes and Sources of Total and Added Sugars in the Canadian Diet

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Brisbois, Tristin D.; Marsden, Sandra L.; Anderson, G. Harvey; Sievenpiper, John L.

2014-01-01

National food supply data and dietary surveys are essential to estimate nutrient intakes and monitor trends, yet there are few published studies estimating added sugars consumption. The purpose of this report was to estimate and trend added sugars intakes and their contribution to total energy intake among Canadians by, first, using Canadian Community Health Survey (CCHS) nutrition survey data of intakes of sugars in foods and beverages, and second, using Statistics Canada availability data a...

Caffeine-containing energy drink improves sprint performance during an international rugby sevens competition.

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Del Coso, Juan; Portillo, Javier; Muñoz, Gloria; Abián-Vicén, Javier; Gonzalez-Millán, Cristina; Muñoz-Guerra, Jesús

2013-06-01

The aim of this study was to determine the effects of a caffeine-containing energy drink on physical performance during a rugby sevens competition. A second purpose was to investigate the post-competition urinary caffeine concentration derived from the energy drink intake. On two non-consecutive days of a friendly tournament, 16 women from the Spanish National rugby sevens Team (mean age and body mass = 23 ± 2 years and 66 ± 7 kg) ingested 3 mg of caffeine per kg of body mass in the form of an energy drink (Fure(®), ProEnergetics) or the same drink without caffeine (placebo). After 60 min for caffeine absorption, participants performed a 15-s maximal jump test, a 6 × 30 m sprint test, and then played three rugby sevens games against another national team. Individual running pace and instantaneous speed during the games were assessed using global positioning satellite (GPS) devices. Urine samples were obtained pre and post-competition. In comparison to the placebo, the ingestion of the energy drink increased muscle power output during the jump series (23.5 ± 10.1 vs. 25.6 ± 11.8 kW, P = 0.05), running pace during the games (87.5 ± 8.3 vs. 95.4 ± 12.7 m/min, P caffeine concentration than the placebo (3.3 ± 0.7 vs. 0.2 ± 0.1 μg/mL; P caffeine in the form of a commercially available energy drink considerably enhanced physical performance during a women's rugby sevens competition.

Caffeine promotes global spatial processing in habitual and non-habitual caffeine consumers

Directory of Open Access Journals (Sweden)

Grace E. Giles

2013-10-01

Full Text Available Information processing is generally biased toward global cues, often at the expense of local information. Equivocal extant data suggests that arousal states may accentuate either a local or global processing bias, at least partially dependent on the nature of the manipulation, task and stimuli. To further differentiate the conditions responsible for such equivocal results we varied caffeine doses to alter physiological arousal states and measured their effect on tasks requiring the retrieval of local versus global spatial knowledge. In a double-blind, repeated-measures design, non-habitual (Exp. 1; N=36, M=42.5±29 mg/day caffeine and habitual (Exp. 2; N=34, M=579.5±311.5 mg/day caffeine caffeine consumers completed four test sessions corresponding to each of four caffeine doses (0 mg, 100 mg, 200 mg, 400 mg. During each test session, participants consumed a capsule containing one of the three doses of caffeine or placebo, waited sixty minutes, and then completed two spatial tasks, one involving memorizing maps and one spatial descriptions. A spatial statement verification task tested local versus global spatial knowledge by differentially probing memory for proximal versus distal landmark relationships. On the map learning task, results indicated that caffeine enhanced memory for distal (i.e. global compared to proximal (i.e. local comparisons at 100 (marginal, 200, and 400 mg caffeine in non-habitual consumers, and marginally beginning at 200 mg caffeine in habitual consumers. On the spatial descriptions task, caffeine enhanced memory for distal compared to proximal comparisons beginning at 100 mg in non-habitual but not habitual consumers. We thus provide evidence that caffeine-induced physiological arousal amplifies global spatial processing biases, and these effects are at least partially driven by habitual caffeine consumption.

Caffeine Reinforces Flavor Preference and Behavior in Moderate Users but Not in Low Caffeine Users

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Dack, Charlotte; Reed, Phil

2009-01-01

The study examined the role of caffeine consumption in caffeine reinforcement. Previous findings have shown that caffeine reinforced flavor preference in moderate caffeine consumers who are caffeine deprived. However, most of these studies have employed rating procedures only, and have not shown the effectiveness of caffeine to reinforce behaviors…

Disagreement between splenic switch-off and myocardial T1-mapping after caffeine intake

NARCIS (Netherlands)

Kuijpers, Dirkjan; van Dijk, Randy; van Assen, Marly; Kaandorp, Theodorus A M; van Dijkman, Paul R M; Vliegenthart, Rozemarijn; van der Harst, Pim; Oudkerk, Matthijs

Caffeine is an adenosine receptor antagonist and a possible cause of inadequate stress perfusion. Splenic switch-off (SSO) and splenic rest-stress T1-mapping have been proposed as indicators of stress adequacy during perfusion cardiac magnetic resonance (CMR). We compared myocardial rest-stress

Consumption of Caffeinated Products and Cardiac Ectopy.

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Dixit, Shalini; Stein, Phyllis K; Dewland, Thomas A; Dukes, Jonathan W; Vittinghoff, Eric; Heckbert, Susan R; Marcus, Gregory M

2016-01-26

Premature cardiac contractions are associated with increased morbidity and mortality. Though experts associate premature atrial contractions (PACs) and premature ventricular contractions (PVCs) with caffeine, there are no data to support this relationship in the general population. As certain caffeinated products may have cardiovascular benefits, recommendations against them may be detrimental. We studied Cardiovascular Health Study participants with a baseline food frequency assessment, 24-hour ambulatory electrocardiography (Holter) monitoring, and without persistent atrial fibrillation. Frequencies of habitual coffee, tea, and chocolate consumption were assessed using a picture-sort food frequency survey. The main outcomes were PACs/h and PVCs/hour. Among 1388 participants (46% male, mean age 72 years), 840 (61%) consumed ≥1 caffeinated product per day. The median numbers of PACs and PVCs/h and interquartile ranges were 3 (1-12) and 1 (0-7), respectively. There were no differences in the number of PACs or PVCs/h across levels of coffee, tea, and chocolate consumption. After adjustment for potential confounders, more frequent consumption of these products was not associated with ectopy. In examining combined dietary intake of coffee, tea, and chocolate as a continuous measure, no relationships were observed after multivariable adjustment: 0.48% fewer PACs/h (95% CI -4.60 to 3.64) and 2.87% fewer PVCs/h (95% CI -8.18 to 2.43) per 1-serving/week increase in consumption. In the largest study to evaluate dietary patterns and quantify cardiac ectopy using 24-hour Holter monitoring, we found no relationship between chronic consumption of caffeinated products and ectopy. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Caffeine synergizes with another coffee component to increase plasma GCSF: linkage to cognitive benefits in Alzheimer's mice.

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Cao, Chuanhai; Wang, Li; Lin, Xiaoyang; Mamcarz, Malgorzata; Zhang, Chi; Bai, Ge; Nong, Jasson; Sussman, Sam; Arendash, Gary

2011-01-01

Retrospective and prospective epidemiologic studies suggest that enhanced coffee/caffeine intake during aging reduces risk of Alzheimer's disease (AD). Underscoring this premise, our studies in AD transgenic mice show that long-term caffeine administration protects against cognitive impairment and reduces brain amyloid-β levels/deposition through suppression of both β- and γ-secretase. Because coffee contains many constituents in addition to caffeine that may provide cognitive benefits against AD, we examined effects of caffeinated and decaffeinated coffee on plasma cytokines, comparing their effects to caffeine alone. In both AβPPsw+PS1 transgenic mice and non-transgenic littermates, acute i.p. treatment with caffeinated coffee greatly and specifically increased plasma levels of granulocyte-colony stimulating factor (GCSF), IL-10, and IL-6. Neither caffeine solution alone (which provided high plasma caffeine levels) or decaffeinated coffee provided this effect, indicating that caffeine synergized with some as yet unidentified component of coffee to selectively elevate these three plasma cytokines. The increase in GCSF is particularly important because long-term treatment with coffee (but not decaffeinated coffee) enhanced working memory in a fashion that was associated only with increased plasma GCSF levels among all cytokines. Since we have previously reported that long-term GCSF treatment enhances cognitive performance in AD mice through three possible mechanisms (e.g., recruitment of microglia from bone marrow, synaptogenesis, and neurogenesis), the same mechanisms could be complimentary to caffeine's established ability to suppress Aβ production. We conclude that coffee may be the best source of caffeine to protect against AD because of a component in coffee that synergizes with caffeine to enhance plasma GCSF levels, resulting in multiple therapeutic actions against AD.

Validity and reproducibility of a self-administered semi-quantitative food-frequency questionnaire for estimating usual daily fat, fibre, alcohol, caffeine and theobromine intakes among Belgian post-menopausal women.

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Bolca, Selin; Huybrechts, Inge; Verschraegen, Mia; De Henauw, Stefaan; Van de Wiele, Tom

2009-01-01

A novel food-frequency questionnaire (FFQ) was developed and validated to assess the usual daily fat, saturated, mono-unsaturated and poly-unsaturated fatty acid, fibre, alcohol, caffeine, and theobromine intakes among Belgian post-menopausal women participating in dietary intervention trials with phyto-oestrogens. The relative validity of the FFQ was estimated by comparison with 7 day (d) estimated diet records (EDR, n 64) and its reproducibility was evaluated by repeated administrations 6 weeks apart (n 79). Although the questionnaire underestimated significantly all intakes compared to the 7 d EDR, it had a good ranking ability (r 0.47-0.94; weighted kappa 0.25-0.66) and it could reliably distinguish extreme intakes for all the estimated nutrients, except for saturated fatty acids. Furthermore, the correlation between repeated administrations was high (r 0.71-0.87) with a maximal misclassification of 7% (weighted kappa 0.33-0.80). In conclusion, these results compare favourably with those reported by others and indicate that the FFQ is a satisfactorily reliable and valid instrument for ranking individuals within this study population.

Faster but not smarter:effects of caffeine and caffeine withdrawal on alertness and performance

OpenAIRE

Rogers, Peter J; Heatherley, Susan V; Mullings, Emma L; Smith, Jessica E

2013-01-01

Despite 100 years of psychopharmacological research, the extent to which caffeine consumption benefits human functioning remains unclear.To measure the effects of overnight caffeine abstinence and caffeine administration as a function of level of habitual caffeine consumption.Medium-high (n = 212) and non-low (n = 157) caffeine consumers completed self-report measures and computer-based tasks before (starting at 10:30 AM) and after double-blind treatment with either caffeine (100 mg, then 150...

Effects of concurrent caffeine and mobile phone exposure on local target probability processing in the human brain.

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Trunk, Attila; Stefanics, Gábor; Zentai, Norbert; Bacskay, Ivett; Felinger, Attila; Thuróczy, György; Hernádi, István

2015-09-23

Millions of people use mobile phones (MP) while drinking coffee or other caffeine containing beverages. Little is known about the potential combined effects of MP irradiation and caffeine on cognitive functions. Here we investigated whether caffeine intake and concurrent exposure to Universal Mobile Telecommunications System (UMTS) MP-like irradiation may interactively influence neuro-cognitive function in an active visual oddball paradigm. In a full factorial experimental design, 25 participants performed a simple visual target detection task while reaction time (RT) and electroencephalogram (EEG) was recorded. Target trials were divided into Low and High probability sets based on target-to-target distance. We analyzed single trial RT and alpha-band power (amplitude) in the pre-target interval. We found that RT was shorter in High vs. Low local probability trials, and caffeine further shortened RT in High probability trials relative to the baseline condition suggesting that caffeine improves the efficiency of implicit short-term memory. Caffeine also decreased pre-target alpha amplitude resulting in higher arousal level. Furthermore, pre-target gamma power positively correlated with RT, which may have facilitated target detection. However, in the present pharmacologically validated study UMTS exposure either alone or in combination with caffeine did not alter RT or pre-stimulus oscillatory brain activity.

Quantitative HPLC Analysis of an Analgesic/Caffeine Formulation: Determination of Caffeine

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Ferguson, Glenda K.

1998-04-01

A modern high performance liquid chromatography (HPLC) laboratory experiment which entails the separation of acetaminophen, aspirin, and caffeine and the quantitative assay of caffeine in commercial mixtures of these compounds has been developed. Our HPLC protocol resolves these compounds in only three minutes with a straightforward chromatographic apparatus which consists of a C-18 column, an isocratic mobile phase, UV detection at 254 nm, and an integrator; an expensive, sophisticated system is not required. The separation is both repeatable and rapid. Moreover, the experiment can be completed in a single three-hour period. The experiment is appropriate for any chemistry student who has completed a minimum of one year of general chemistry and is ideal for an analytical or instrumental analysis course. The experiment detailed herein involves the determination of caffeine in Goody's Extra Strength Headache Powders, a commercially available medication which contains acetaminophen, aspirin, and caffeine as active ingredients. However, the separation scheme is not limited to this brand of medication nor is it limited to caffeine as the analyte. With only minor procedural modifications, students can simultaneously quantitate all of these compounds in a commercial mixture. In our procedure, students prepare a series of four caffeine standard solutions as well as a solution from a pharmaceutical analgesic/caffeine mixture, chromatographically analyze each solution in quadruplicate, and plot relative average caffeine standard peak area versus concentration. From the mathematical relationship that results, the concentration of caffeine in the commercial formulation is obtained. Finally, the absolute standard deviation of the mean concentration is calculated.

Effects of caffeine and caffeine withdrawal on mood and cognitive performance degraded by sleep restriction.

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Rogers, Peter J; Heatherley, Susan V; Hayward, Robert C; Seers, Helen E; Hill, Joanne; Kane, Marian

2005-06-01

It has been suggested that caffeine is most likely to benefit mood and performance when alertness is low. To measure the effects of caffeine on psychomotor and cognitive performance, mood, blood pressure and heart rate in sleep-restricted participants. To do this in a group of participants who had also been previously deprived of caffeine for 3 weeks, thereby potentially removing the confounding effects of acute caffeine withdrawal. Participants were moderate to moderate-high caffeine consumers who were provided with either decaffeinated tea and/or coffee for 3 weeks (LTW) or regular tea and/or coffee for 3 weeks (overnight caffeine-withdrawn participants, ONW). Then, following overnight caffeine abstinence, they were tested on a battery of tasks assessing mood, cognitive performance, etc. before and after receiving caffeine (1.2 mg/kg) or on another day after receiving placebo. Final analyses were based on 17 long-term caffeine-withdrawn participants (LTW) and 17 ONW participants whose salivary caffeine levels on each test day confirmed probable compliance with the instructions concerning restrictions on consumption of caffeine-containing drinks. Acute caffeine withdrawal (ONW) had a number of negative effects, including impairment of cognitive performance, increased headache, and reduced alertness and clear-headedness. Caffeine (versus placebo) did not significantly improve cognitive performance in LTW participants, although it prevented further deterioration of performance in ONW participants. Caffeine increased tapping speed (but tended to impair hand steadiness), increased blood pressure, and had some effects on mood in both groups. The findings provide strong support for the withdrawal reversal hypothesis. In particular, cognitive performance was found to be affected adversely by acute caffeine withdrawal and, even in the context of alertness lowered by sleep restriction, cognitive performance was not improved by caffeine in the absence of these withdrawal

Caffeine overdose

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... this page: //medlineplus.gov/ency/article/002579.htm Caffeine overdose To use the sharing features on this page, please enable JavaScript. Caffeine is a substance that exists naturally in certain ...

Subjective, behavioral, and physiological effects of acute caffeine in light, nondependent caffeine users.

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Childs, Emma; de Wit, Harriet

2006-05-01

Caffeine produces mild psychostimulant effects that are thought to underlie its widespread use. However, the direct effects of caffeine are difficult to evaluate in regular users of caffeine because of tolerance and withdrawal. Indeed, some researchers hypothesize that the psychostimulant effects of caffeine are due largely to the reversal of withdrawal and question whether there are direct effects of caffeine consumption upon mood, alertness, or mental performance in nondependent individuals. This study investigated the physiological, subjective, and behavioral effects of 0, 50, 150, and 450 mg caffeine in 102 light, nondependent caffeine users. Using a within-subjects design, subjects participated in four experimental sessions, in which they received each of the four drug conditions in random order under double blind conditions. Participants completed subjective effects questionnaires and vital signs were measured before and at repeated time points after drug administration. Forty minutes after the capsules were ingested, subjects completed behavioral tasks that included tests of sustained attention, short-term memory, psychomotor performance, and behavioral inhibition. Caffeine significantly increased blood pressure, and produced feelings of arousal, positive mood, and high. Caffeine increased the number of hits and decreased reaction times in a vigilance task, but impaired performance on a memory task. We confirm that acute doses of caffeine, at levels typically found in a cup of coffee, produce stimulant-like subjective effects and enhance performance in light, nondependent caffeine users. These findings support the idea that the drug has psychoactive effects even in the absence of withdrawal.

Caffeine's implications for women's health and survey of obstetrician-gynecologists' caffeine knowledge and assessment practices.

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Anderson, Britta L; Juliano, Laura M; Schulkin, Jay

2009-09-01

Caffeine has relevance for women's health and pregnancy, including significant associations with spontaneous abortion and low birth weight. According to scientific data, pregnant women and women of reproductive age should be advised to limit their caffeine consumption. This article reviews the implications of caffeine for women's psychological and physical health, and presents data on obstetrician-gynecologists' (ob-gyns) knowledge and practices pertaining to caffeine. Ob-gyns (N = 386) who are members of the American College of Obstetricians and Gynecologists' Collaborative Ambulatory Research Network responded to a 21-item survey about caffeine. Although most knew that caffeine is passed through breast milk, only 24.8% were aware that caffeine metabolism significantly slows as pregnancy progresses. Many respondents were not aware of the caffeine content of commonly used products, such as espresso and Diet Coke, with 14.3% and 57.8% indicating amounts within an accurate range, respectively. Furthermore, ob-gyns did not take into account large differences in caffeine content across different caffeinated beverages with most recommending one to two servings of coffee or tea or soft drinks per day. There was substantial inconsistency in what was considered to be "high levels" of maternal caffeine consumption, with only 31.6% providing a response. When asked to indicate the risk that high levels of caffeine have on various pregnancy outcomes, responses were not consistent with scientific data. For example, respondents overestimated the relative risk of stillbirths and underestimated the relative risk of spontaneous abortion. There was great variability in assessment and advice practices pertaining to caffeine. More than half advise their pregnant patients to consume caffeine under certain circumstances, most commonly to alleviate headache and caffeine withdrawal. The data suggest that ob-gyns could benefit from information about caffeine and its relevance to their

Caffeine Use among Active Duty Navy and Marine Corps Personnel

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Knapik, Joseph J.; Trone, Daniel W.; McGraw, Susan; Steelman, Ryan A.; Austin, Krista G.; Lieberman, Harris R.

2016-01-01

Data from the National Health and Nutrition Examination Survey (NHANES) indicate 89% of Americans regularly consume caffeine, but these data do not include military personnel. This cross-sectional study examined caffeine use in Navy and Marine Corps personnel, including prevalence, amount of daily consumption, and factors associated with use. A random sample of Navy and Marine Corps personnel was contacted and asked to complete a detailed questionnaire describing their use of caffeine-containing substances, in addition to their demographic, military, and lifestyle characteristics. A total of 1708 service members (SMs) completed the questionnaire. Overall, 87% reported using caffeinated beverages ≥1 time/week, with caffeine users consuming a mean ± standard error of 226 ± 5 mg/day (242 ± 7 mg/day for men, 183 ± 8 mg/day for women). The most commonly consumed caffeinated beverages (% users) were coffee (65%), colas (54%), teas (40%), and energy drinks (28%). Multivariable logistic regression modeling indicated that characteristics independently associated with caffeine use (≥1 time/week) included older age, white race/ethnicity, higher alcohol consumption, and participating in less resistance training. Prevalence of caffeine use in these SMs was similar to that reported in civilian investigations, but daily consumption (mg/day) was higher. PMID:27735834

Caffeine Use among Active Duty Navy and Marine Corps Personnel

Directory of Open Access Journals (Sweden)

Joseph J. Knapik

2016-10-01

Full Text Available Data from the National Health and Nutrition Examination Survey (NHANES indicate 89% of Americans regularly consume caffeine, but these data do not include military personnel. This cross-sectional study examined caffeine use in Navy and Marine Corps personnel, including prevalence, amount of daily consumption, and factors associated with use. A random sample of Navy and Marine Corps personnel was contacted and asked to complete a detailed questionnaire describing their use of caffeine-containing substances, in addition to their demographic, military, and lifestyle characteristics. A total of 1708 service members (SMs completed the questionnaire. Overall, 87% reported using caffeinated beverages ≥1 time/week, with caffeine users consuming a mean ± standard error of 226 ± 5 mg/day (242 ± 7 mg/day for men, 183 ± 8 mg/day for women. The most commonly consumed caffeinated beverages (% users were coffee (65%, colas (54%, teas (40%, and energy drinks (28%. Multivariable logistic regression modeling indicated that characteristics independently associated with caffeine use (≥1 time/week included older age, white race/ethnicity, higher alcohol consumption, and participating in less resistance training. Prevalence of caffeine use in these SMs was similar to that reported in civilian investigations, but daily consumption (mg/day was higher.

Caffeine, fatigue, and cognition.

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Lorist, Monicque M; Tops, Mattie

2003-10-01

Effects of caffeine and fatigue are discussed with special attention to adenosine-dopamine interactions. Effects of caffeine on human cognition are diverse. Behavioural measurements indicate a general improvement in the efficiency of information processing after caffeine, while the EEG data support the general belief that caffeine acts as a stimulant. Studies using ERP measures indicate that caffeine has an effect on attention, which is independent of specific stimulus characteristics. Behavioural effects on response related processes turned out to be mainly related to more peripheral motor processes. Recent insights in adenosine and dopamine physiology and functionality and their relationships with fatigue point to a possible modulation by caffeine of mechanisms involved in the regulation of behavioural energy expenditure.

Beliefs, Behaviors, and Contexts of Adolescent Caffeine Use: A Focus Group Study.

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Ludden, Alison B; O'Brien, Elizabeth M; Pasch, Keryn E

2017-07-29

Caffeinated products are widely available to adolescents, and consumption of caffeine products-energy drinks and coffee in particular-is on the rise in this age group (Branum, Rossen, & Schoendorf, 2014). Yet, little is known about the psychosocial context of caffeine use. Previous studies on adolescent caffeine use have focused on caffeine's acute physiological effects, rather than the psychosocial contexts and beliefs regarding different types of caffeinated beverages (e.g., coffee, energy drinks, soda). The current research examines the contexts and beliefs associated with adolescents' use of caffeinated beverages (e.g., coffee, energy drinks, soda) using a focus group approach. Eleven focus group interviews (49 total participants) addressed adolescents' motivations for and patterns of caffeine use; they were transcribed and axial coding was used to identify common themes. Coffee and energy drinks were perceived to be the most popular caffeinated beverages. Reasons for consuming caffeine included the effect of caffeine as a stimulant, the pleasant feelings experienced when drinking it, and the fact that caffeine was available. As for contexts, coffee was consumed in more diverse social contexts than other caffeinated beverages. Friends and sports were the most popular contexts for energy drink use. The present findings inform adolescent health promotion efforts and provide researchers and practitioners alike detailed information in adolescents' own words about how and why they use caffeine. Adolescents' beliefs about caffeinated products are not uniform; the reasons adolescents articulate regarding their use of coffee, soda, and energy drinks are different across contexts and beverage type.

Genotoxicity of antiobesity drug orlistat and effect of caffeine intervention: an in vitro study.

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Chakrabarti, Manoswini; Ghosh, Ilika; Jana, Aditi; Ghosh, Manosij; Mukherjee, Anita

2017-07-01

Obesity is a major global health problem associated with various adverse effects. Pharmacological interventions are often necessary for the management of obesity. Orlistat is an FDA-approved antiobesity drug which is a potent inhibitor of intestinal lipases. In the current study, orlistat was evaluated for its genotoxic potential in human lymphocyte cells in vitro and was compared with that of another antiobesity drug sibutramine, presently withdrawn from market due its undesirable health effects. Caffeine intake may be an additional burden in people using anorectic drugs, therefore, further work is needed to be carried out to evaluate the possible effects of caffeine on orlistat-induced DNA damage. Human lymphocytes were exposed to orlistat (250, 500 and 1000 μg/ml), sibutramine (250, 500 and 1000 μg/ml) and caffeine (25, 50, 75, 100, 125 and 150 μg/ml) to assess their genotoxicity by comet assay in vitro. In addition, lymphocytes were co-incubated with caffeine (50, 75 and 100 μg/ml) and a single concentration of orlistat (250 μg/ml). Orlistat and sibutramine were genotoxic at all concentrations tested, sibutramine being more genotoxic. Caffeine was found to be genotoxic at concentrations 125 μg/ml and above. Co-treatment of orlistat with non-genotoxic concentrations (50, 75 and 100 μg/ml) of caffeine lead to a decrease in DNA damage. Orlistat can induce DNA damage in human lymphocytes in vitro and caffeine was found to reduce orlistat-induced genotoxicity.

Postprandial appetite ratings are reproducible and moderately related to total day energy intakes, but not ad libitum lunch energy intakes, in healthy young women.

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Tucker, Amy J; Heap, Sarah; Ingram, Jessica; Law, Marron; Wright, Amanda J

2016-04-01

Reproducibility and validity testing of appetite ratings and energy intakes are needed in experimental and natural settings. Eighteen healthy young women ate a standardized breakfast for 8 days. Days 1 and 8, they rated their appetite (Hunger, Fullness, Desire to Eat, Prospective Food Consumption (PFC)) over a 3.5 h period using visual analogue scales, consumed an ad libitum lunch, left the research center and recorded food intake for the remainder of the day. Days 2-7, participants rated their at-home Hunger at 0 and 30 min post-breakfast and recorded food intake for the day. Total area under the curve (AUC) over the 180 min period before lunch, and energy intakes were calculated. Reproducibility of satiety measures between days was evaluated using coefficients of repeatability (CR), coefficients of variation (CV) and intra-class coefficients (ri). Correlation analysis was used to examine validity between satiety measures. AUCs for Hunger, Desire to Eat and PFC (ri = 0.73-0.78), ad libitum energy intakes (ri = 0.81) and total day energy intakes (ri​ = 0.48) were reproducible; fasted ratings were not. Average AUCs for Hunger, Desire to Eat and PFC, Desire to Eat at nadir and PFC at fasting, nadir and 180 min were correlated to total day energy intakes (r = 0.50-0.77, P < 0.05), but no ratings were correlated to lunch consumption. At-home Hunger ratings were weakly reproducible but not correlated to reported total energy intakes. Satiety ratings did not concur with next meal intake but PFC ratings may be useful predictors of intake. Overall, this study adds to the limited satiety research on women and challenges the accepted measures of satiety in an experimental setting. Copyright © 2016 Elsevier Ltd. All rights reserved.

Feeling smart: Effects of caffeine and glucose on cognition, mood and self-judgment.

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Ullrich, Susann; de Vries, Yfke C; Kühn, Simone; Repantis, Dimitris; Dresler, Martin; Ohla, Kathrin

2015-11-01

During education and early career, young adults often face examinations and assessment centers. Coffee and energy drinks are convenient and commonly used to enhance or maintain performance in these situations. Whether these macronutrients improve performance in a demanding and drawn-out multi-task situation is not clear. Using double-blind, placebo-controlled studies, we set out to examine the effects of caffeine and glucose in an assessment center-like situation, under natural consumption conditions, in a group of young adults who were heterogeneous with respect to consumption patterns. We measured multi-task performance including logical thinking, processing speed, numeric and verbal memory, attention and the ability to concentrate, and mood over a two-hour period. Caffeine and glucose were administered in common beverages with appropriate placebo controls allowing the assessment of psychological effects of expectancy. Importantly, and in contrast to most previous studies, participants retained their habitual caffeine and sugar intake (studies 1 and 2) as this represents common behavior. Based on the bulk of literature, we hypothesized that (i) caffeine enhances attentional performance and mood, while performance in more complex tasks will remain unchanged, and that (ii) glucose enhances performance on memory tasks accompanied with negative mood. Our results provide evidence that neither caffeine nor glucose significantly influence cognitive performance when compared with placebo, water, or no treatment controls in a multi-task setting. Yet, caffeine and, by trend, placebo improve dispositions such that participants perceive preserved mental energy throughout the test procedure. These subjective effects were stronger after 24 h caffeine abstinence (study 3). Future studies will have to address whether these mood changes actually result in increased motivation during a challenging task.

Atrial fibrillation associated with chocolate intake abuse and chronic salbutamol inhalation abuse.

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Patanè, Salvatore; Marte, Filippo; La Rosa, Felice Carmelo; Rocca, Roberto La

2010-11-19

The use of substances as the substrate for atrial fibrillation is not frequently recognized. Chocolate is derived from the roasted seeds of the plant theobroma cacao and its components are the methylxanthine alkaloids theobromine and caffeine. Caffeine is a methylxanthine whose primary biological effect is the competitive antagonism of the adenosine receptor. Normal consumption of caffeine was not associated with risk of atrial fibrillation or flutter. Sympathomimetic effects, due to circulating catecholamines cause the cardiac manifestations of caffeine overdose toxicity, produce tachyarrhythmias such as supraventricular tachycardia, atrial fibrillation, ventricular tachycardia, and ventricular fibrillation.The commonly used doses of inhaled or nebulized salbutamol induced no acute myocardial ischaemia, arrhythmias or changes in heart rate variability in patients with coronary artery disease and clinically stable asthma or chronic obstructive pulmonary disease. Two-week salbutamol treatment shifts the cardiovascular autonomic regulation to a new level characterized by greater sympathetic responsiveness and slight beta2-receptor tolerance. We present a case of atrial fibrillation associated with chocolate intake abuse in a 19-year-old Italian woman with chronic salbutamol inhalation abuse. This case focuses attention on chocolate intake abuse associated with chronic salbutamol abuse as the substrate for atrial fibrillation. Copyright © 2008 Elsevier Ireland Ltd. All rights reserved.

Caffeine ingestion acutely enhances muscular strength and power but not muscular endurance in resistance-trained men.

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Grgic, Jozo; Mikulic, Pavle

2017-09-01

The goal of this randomized, double-blind, cross-over study was to assess the acute effects of caffeine ingestion on muscular strength and power, muscular endurance, rate of perceived exertion (RPE), and pain perception (PP) in resistance-trained men. Seventeen volunteers (mean ± SD: age = 26 ± 6 years, stature = 182 ± 9 cm, body mass = 84 ± 9 kg, resistance training experience = 7 ± 3 years) consumed placebo or 6 mg kg -1 of anhydrous caffeine 1 h before testing. Muscular power was assessed with seated medicine ball throw and vertical jump exercises, muscular strength with one-repetition maximum (1RM) barbell back squat and bench press exercises, and muscular endurance with repetitions of back squat and bench press exercises (load corresponding to 60% of 1RM) to momentary muscular failure. RPE and PP were assessed immediately after the completion of the back squat and bench press exercises. Compared to placebo, caffeine intake enhanced 1RM back squat performance (+2.8%; effect size [ES] = 0.19; p = .016), which was accompanied by a reduced RPE (+7%; ES = 0.53; p = .037), and seated medicine ball throw performance (+4.3%, ES = 0.32; p = .009). Improvements in 1RM bench press were not noted although there were significant (p = .029) decreases in PP related to this exercise when participants ingested caffeine. The results point to an acute benefit of caffeine intake in enhancing lower-body strength, likely due to a decrease in RPE; upper-, but not lower-body power; and no effects on muscular endurance, in resistance-trained men. Individuals competing in events in which strength and power are important performance-related factors may consider taking 6 mg kg -1 of caffeine pre-training/competition for performance enhancement.

Is caffeine a cognitive enhancer?

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Nehlig, Astrid

2010-01-01

The effects of caffeine on cognition were reviewed based on the large body of literature available on the topic. Caffeine does not usually affect performance in learning and memory tasks, although caffeine may occasionally have facilitatory or inhibitory effects on memory and learning. Caffeine facilitates learning in tasks in which information is presented passively; in tasks in which material is learned intentionally, caffeine has no effect. Caffeine facilitates performance in tasks involving working memory to a limited extent, but hinders performance in tasks that heavily depend on working memory, and caffeine appears to rather improve memory performance under suboptimal alertness conditions. Most studies, however, found improvements in reaction time. The ingestion of caffeine does not seem to affect long-term memory. At low doses, caffeine improves hedonic tone and reduces anxiety, while at high doses, there is an increase in tense arousal, including anxiety, nervousness, jitteriness. The larger improvement of performance in fatigued subjects confirms that caffeine is a mild stimulant. Caffeine has also been reported to prevent cognitive decline in healthy subjects but the results of the studies are heterogeneous, some finding no age-related effect while others reported effects only in one sex and mainly in the oldest population. In conclusion, it appears that caffeine cannot be considered a ;pure' cognitive enhancer. Its indirect action on arousal, mood and concentration contributes in large part to its cognitive enhancing properties.

The effects of caffeine and expectancy on attention and memory.

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Oei, Adam; Hartley, Laurence R

2005-04-01

The present study contrasted caffeine's effects on individuals who expect caffeine to stimulate them and those who do not. Secondly, whether a message that caffeine rather than placebo was administered would also affect these two groups of subjects differently was investigated. The study was conducted single-blind in a 2x2x2 mixed design. The between subjects factor was whether they expected caffeine to stimulate them (E+) or not (E-) according to their self reports obtained before the experiment began. The within subjects factors were message (told caffeine vs told placebo) and beverage type (given caffeine vs placebo). Sixteen subjects in each group (n=32) performed on signal detection, memory scanning and delayed free recall tasks following ingestion of either caffeinated or decaffeinated coffee on two sessions each, a total of four experimental sessions. On each session, subjects were given a message regarding their drink (told caffeine vs told placebo). However, on two sessions there was a mismatch between the message and drink given. For signal detection, performance under caffeine was better than placebo in the E+ but not the E- group. However, subjects in the E+ group did not benefit more than the E- group in either message condition. On memory scanning, detections and false alarms did not differ for either beverage, nor was there a differential finding in the E+ and E- groups. However, reaction time under caffeine condition was shorter. No effects of message were found. Caffeine and message also did not have any effect on performance on the delayed free recall task. The hypothesis that caffeine and message would affect E+ and E- subjects differentially was partly supported. Copyright (c) 2005 John Wiley & Sons, Ltd.

Caffeine: Friend or Foe?

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Doepker, Candace; Lieberman, Harris R; Smith, Andrew Paul; Peck, Jennifer D; El-Sohemy, Ahmed; Welsh, Brian T

2016-01-01

The debate on the safety of and regulatory approaches for caffeine continues among various stakeholders and regulatory authorities. This decision-making process comes with significant challenges, particularly when considering the complexities of the available scientific data, making the formulation of clear science-based regulatory guidance more difficult. To allow for discussions of a number of key issues, the North American Branch of the International Life Sciences Institute (ILSI) convened a panel of subject matter experts for a caffeine-focused session entitled "Caffeine: Friend or Foe?," which was held during the 2015 ILSI Annual Meeting. The panelists' expertise covered topics ranging from the natural occurrence of caffeine in plants and interindividual metabolism of caffeine in humans to specific behavioral, reproductive, and cardiovascular effects related to caffeine consumption. Each presentation highlighted the potential risks, benefits, and challenges that inform whether caffeine exposure warrants concern. This paper aims to summarize the key topics discussed during the session.

The influence of caffeine ingestion on strength and power performance in female team-sport players.

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Ali, Ajmol; O'Donnell, Jemma; Foskett, Andrew; Rutherfurd-Markwick, Kay

2016-01-01

The aim of this study was to examine the influence of caffeine supplementation on knee flexor and knee extensor strength before, during and after intermittent running exercise in female team-sport players taking oral contraceptive steroids (OCS). Ten healthy females (24 ± 4 years; 59.7 ± 3.5 kg; undertaking 2-6 training sessions per week) taking low-dose monophasic oral contraceptives of the same hormonal composition took part in a randomised, double-blind, placebo-controlled crossover-design trial. Sixty minutes following the ingestion of a capsule containing 6 mg∙kg -1 body mass anhydrous caffeine or artificial sweetener (placebo), participants completed a 90-min intermittent treadmill-running protocol. Isometric strength performance and eccentric and concentric strength and power of the knee flexors and knee extensors (using isokinetic dynamometer), as well as countermovement jump (CMJ), was measured before, during and after the exercise protocol, as well as ~12 h post-exercise. Blood samples were taken before, during and post-exercise to measure glucose, insulin and free fatty acids (FFA). Caffeine supplementation significantly increased eccentric strength of the knee flexors ( P  performance. FFA was elevated with caffeine supplementation over time ( P  caffeine intake. Caffeine supplementation increased eccentric strength and power in female team-sport players taking OCS both during an intermittent running protocol and the following morning.

Systematic review of randomised controlled trials of the effects of caffeine or caffeinated drinks on blood glucose concentrations and insulin sensitivity in people with diabetes mellitus.

Science.gov (United States)

Whitehead, N; White, H

2013-04-01

Compounds other than macronutrients have been shown to influence blood glucose concentrations and insulin sensitivity in people with diabetes, with caffeine being one such substance. The present study systematically reviewed the evidence of the effects of caffeine on blood glucose concentrations and/or insulin sensitivity in people with diabetes. Four databases, including MEDLINE and EMBASE, were searched up to 1 February 2012. Randomised controlled trials (RCTs) investigating the effects of caffeine on blood glucose and/or insulin sensitivity in humans, diagnosed with type I, type II or gestational diabetes mellitus (GDM), were included. Quality assessment and data extraction were conducted and agreed by both authors. Of 253 articles retrieved, nine trials (134 participants) were identified. Trials in people with type II diabetes demonstrated that the ingestion of caffeine (approximately 200-500 mg) significantly increased blood glucose concentrations by 16-28% of the area under the curve (AUC) and insulin concentrations by 19-48% of the AUC when taken prior to a glucose load, at the same time as decreasing insulin sensitivity by 14-37%. In type I diabetes, trials indicated enhanced recognition and a reduced duration of hypoglycaemic episodes following ingestion of 400-500 mg caffeine, without altering glycated haemoglobin. In GDM, a single trial demonstrated that approximately 200 mg of caffeine induced a decrease in insulin sensitivity by 18% and a subsequent increase in blood glucose concentrations by 19% of the AUC. Evidence indicates a negative effect of caffeine intake on blood glucose control in individuals with type II diabetes, as replicated in a single trial in GDM. Larger-scale RCTs of longer duration are needed to determine the effects of timing and dose. Early indications of a reduced duration and an improved awareness of hypoglycaemia in type I diabetes require further confirmation. © 2013 The Authors Journal of Human Nutrition and Dietetics �

The Effects of Caffeine Use on Driving Safety Among Truck Drivers Who Are Habitual Caffeine Users.

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Heaton, Karen; Griffin, Russell

2015-08-01

The purpose of this study was to describe caffeine use among a group of habitual caffeine users, truck drivers, and to explore the associations between caffeine use and critical safety events by age in the naturalistic work setting. A secondary analysis of existing data from the Naturalistic Truck Driving Study was conducted. Analyses focused on the association between sleep and caffeine consumption by duty status, comparisons of sleep and caffeine use by age, and the associations between caffeine use and safety-critical events (SCEs). Findings indicated differences in caffeine use by duty status. However, no difference in sleep time by duty status, or between sleep time and caffeine use was found regardless of when the caffeine was consumed during the 5 hours prior to sleep. Sleep time did not vary significantly by age, although increasing age was associated with decreased caffeine use. Overall, a 6% reduction in the rate of SCEs per eight ounces of caffeinated beverage consumed was found. This study makes a unique scientific contribution because it uses real-time observations of truckers in the naturalistic work setting. It also does not involve caffeine withdrawal but rather an investigation of the effects of the naturalistic consumption of caffeine on sleep and driving performance. Findings suggest that caffeine use among habitual users offers a protective effect for safety-critical driving events. Occupational health nurses may use this information to counsel workers in the use of caffeine to enhance driving safety. © 2015 The Author(s).

Influence of the urine flow rate on some caffeine metabolite ratios used to assess CYP1A2 activity.

Science.gov (United States)

Sinués, Blanca; Fanlo, Ana; Bernal, María Luisa; Mayayo, Esteban; Soriano, María Antonia; Martínez-Ballarin, Enrique

2002-12-01

Five established metabolite ratios (MRs) to measure P450 CYP1A2 activity--MR1 (17X + 17U)/137X, MR2 (AFMU + 1X + 1U)/17U, MR3 (17X/137X), MR4 (AFMU + 1X + 1U + 17X + 17U)/137X, and MR5 (AFMU + 1X + 1U)/17X--were calculated in urine 4-5 hours after caffeine intake. First, to assess the potential of omeprazole to induce CYP1A2 activity, a caffeine test was performed in 27 subjects on two occasions: before and after 14 days on omeprazole (20 mg/day). Samples of urine were analyzed by high-performance liquid chromatography (HPLC) to quantify caffeine and metabolites used to calculate the different caffeine MRs. MR1, MR3, and MR4 were enhanced after treatment; the percentage of change was inversely associated with that of the urine flow, with r values of -0.48, -0.49, and -0.47, respectively. However, MR2 or MR5 were not modified. To determine the reason for these contradictory results, the authors analyzed data of metabolites, ratios, and their components (numerators and denominators) from 152 subjects (who underwent one caffeine test) and their relationship with the urinary flow. Caffeine concentration in urine was the only compound nondependent on the urine flow. Consistently, ratios containing caffeine (MR1, MR3, and MR4) were highly influenced by the rate of urine excretion, since the flow dependence of their numerators is not canceled out by that of caffeine in their denominators. The dependency of the caffeine excretion on renal factors may explain the opposite results found with the different ratios in the aforementioned prospective study of drug interaction, the absence of closer correlations of the five MRs to each other, the discrepancies about the type of frequency distribution of the different MRs (either normal or multimodal), and the higher sensitivity of MR2 to detect gender differences in CYP1A2 activity found in this study. In summary, the data clearly emphasize the need for a strict control of the liquid intake to avoid high urine flows when MRs

Performance effects and metabolic consequences of caffeine and caffeinated energy drink consumption on glucose disposal.

Science.gov (United States)

Shearer, Jane; Graham, Terry E

2014-10-01

This review documents two opposing effects of caffeine and caffeine-containing energy drinks, i.e., their positive effects on athletic performance and their negative impacts on glucose tolerance in the sedentary state. Analysis of studies examining caffeine administration prior to performance-based exercise showed caffeine improved completion time by 3.6%. Similar analyses following consumption of caffeine-containing energy drinks yielded positive, but more varied, benefits, which were likely due to the diverse nature of the studies performed, the highly variable composition of the beverages consumed, and the range of caffeine doses administered. Conversely, analyses of studies administering caffeine prior to either an oral glucose tolerance test or insulin clamp showed a decline in whole-body glucose disposal of ~30%. The consequences of this resistance are unknown, but there may be implications for the development of a number of chronic diseases. Both caffeine-induced performance enhancement and insulin resistance converge with the primary actions of caffeine on skeletal muscle. © 2014 International Life Sciences Institute.

Faster but not smarter: effects of caffeine and caffeine withdrawal on alertness and performance.

Science.gov (United States)

Rogers, Peter J; Heatherley, Susan V; Mullings, Emma L; Smith, Jessica E

2013-03-01

Despite 100 years of psychopharmacological research, the extent to which caffeine consumption benefits human functioning remains unclear. To measure the effects of overnight caffeine abstinence and caffeine administration as a function of level of habitual caffeine consumption. Medium-high (n = 212) and non-low (n = 157) caffeine consumers completed self-report measures and computer-based tasks before (starting at 10:30 AM) and after double-blind treatment with either caffeine (100 mg, then 150 mg) or placebo. The first treatment was given at 11:15 AM and the second at 12:45 PM, with post-treatment measures repeated twice between 1:45 PM and 3:30 PM. Caffeine withdrawal was associated with some detrimental effects at 10:30 AM, and more severe effects, including greater sleepiness, lower mental alertness, and poorer performance on simple reaction time, choice reaction time and recognition memory tasks, later in the afternoon. Caffeine improved these measures in medium-high consumers but, apart from decreasing sleepiness, had little effect on them in non-low consumers. The failure of caffeine to increase mental alertness and improve mental performance in non-low consumers was related to a substantial caffeine-induced increase in anxiety/jitteriness that offset the benefit of decreased sleepiness. Caffeine enhanced physical performance (faster tapping speed and faster simple and choice reaction times) in both medium-high and non-low consumers. While caffeine benefits motor performance and tolerance develops to its tendency to increase anxiety/jitteriness, tolerance to its effects on sleepiness means that frequent consumption fails to enhance mental alertness and mental performance.

Effect of moderate intakes of different tea catechins and caffeine on acute measures of energy metabolism under sedentary conditions

DEFF Research Database (Denmark)

Gregersen, N.T.; Bitz, C.; Krog-Mikkelsen, I.

2009-01-01

Green tea may stimulate energy metabolism; however, it is unclear if acute effects are caused by specific catechins, caffeine or their combination. The objective of the present study was to examine the separate and combined effects of different catechins and caffeine on energy expenditure (EE...... and fat oxidation. The maximum observed effect on EE of about 2 % could still be meaningful for energy balance over much longer period of exposure. However, higher short-term effects reported in the literature may reflect variations in green tea extracts, added caffeine, or synergies with physical...... activity. The specific mechanisms and conditions that may underpin observed longer-term benefits of catechin-enriched green tea consumption on body composition remain to be confirmed....

Caffeine, extraversion and working memory.

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Smith, Andrew P

2013-01-01

Research has shown that extraverts performing a working memory task benefit more from caffeine than do introverts. The present study aimed to replicate this and extend our knowledge by using a lower dose of caffeine (65 mg) and a range of tasks related to different components of working memory. In addition, tasks assessing psychomotor speed and the encoding of new information were included to determine whether caffeine-extraversion interactions were restricted to working memory tasks. A double-blind design was used, with 128 participants being randomly assigned to caffeinated or de-caffeinated coffee conditions. The results showed that caffeine interacted with extraversion in the predicted direction for serial recall and running memory tasks. Caffeine improved simple reaction time and the speed of encoding of new information, effects which were not modified by extraversion. These results suggest possible biological mechanisms underlying effects of caffeine on cognitive performance.

Validity and Reproducibility of a Self-Administered Semi-Quantitative Food-Frequency Questionnaire for Estimating Usual Daily Fat, Fibre, Alcohol, Caffeine and Theobromine Intakes among Belgian Post-Menopausal Women

Directory of Open Access Journals (Sweden)

Selin Bolca

2009-01-01

Full Text Available A novel food-frequency questionnaire (FFQ was developed and validated to assess the usual daily fat, saturated, mono-unsaturated and poly-unsaturated fatty acid, fibre, alcohol, caffeine, and theobromine intakes among Belgian post-menopausal women participating in dietary intervention trials with phyto-oestrogens. The relative validity of the FFQ was estimated by comparison with 7 day (d estimated diet records (EDR, n 64 and its reproducibility was evaluated by repeated administrations 6 weeks apart (n 79. Although the questionnaire underestimated significantly all intakes compared to the 7 d EDR, it had a good ranking ability (r 0.47-0.94; weighted κ 0.25-0.66 and it could reliably distinguish extreme intakes for all the estimated nutrients, except for saturated fatty acids. Furthermore, the correlation between repeated administrations was high (r 0.71-0.87 with a maximal misclassification of 7% (weighted κ 0.33-0.80. In conclusion, these results compare favourably with those reported by others and indicate that the FFQ is a satisfactorily reliable and valid instrument for ranking individuals within this study population.

Caffeine, fatigue, and cognition

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Lorist, M.M.; Tops, M.

2003-01-01

Effects of caffeine and fatigue are discussed with special attention to adenosine-dopamine interactions. Effects of caffeine on human cognition are diverse. Behavioural measurements indicate a general improvement in the efficiency of information processing after caffeine, while the EEG data support

Caffeine and sleep-deprivation mediated changes in open-field behaviours, stress response and antioxidant status in mice.

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Onaolapo, J Olakunle; Onaolapo, Y Adejoke; Akanmu, A Moses; Olayiwola, Gbola

2016-01-01

Effects of daily caffeine consumption on open-field behaviours, serum corticosterone and brain antioxidant levels were investigated after six hours of total sleep-deprivation in prepubertal mice. We tested the hypothesis that daily caffeine consumption may significantly alter behaviour, stress and antioxidative response of prepubertal mice to an acute episode of total sleep-deprivation. Prepubertal Swiss mice of both sexes were assigned to two main groups of 120 each (subdivided into 6 groups of 10 each, based on sex), and administered vehicle or graded oral doses of caffeine (10, 20, 40, 80 and 120 mg/kg/day) for 14 days. On day 14, a main group was subjected to 6 h of total sleep-deprivation by 'gentle-handling'. Open-field behaviours were then assessed in both groups, after which animals were euthanized, and levels of corticosterone, superoxide dismutase and glutathione peroxidase assayed. Horizontal locomotion, rearing and grooming increased significantly, compared to control, with sleep-deprived (SD) mice showing stronger caffeine-driven responses at higher doses; and SD female mice showing sustained response to caffeine, compared to respective males. Plasma corticosterone increased with increasing doses of caffeine in both non sleep-deprived (NSD) and SD mice; although SD mice had higher corticosterone levels. Sleep-deprivation and/or higher doses of caffeine were associated with derangements in brain antioxidant levels. Repeated caffeine consumption and/or acute sleep-deprivation led to significant changes in pattern of open-field behaviour and stress/antioxidant response in mice. Responses seen in the study are probably due to modulatory effects of caffeine on the total body response to stressful stimuli.

Caffeine/sleep-deprivation interaction in mice produces complex memory effects.

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Onaolapo, Olakunle J; Onaolapo, Adejoke Y; Akanmu, Moses A; Olayiwola, Gbola

2015-07-01

Sleep deprivation negatively impacts memory, causing deficits in memory processes. Of interest is any agent that can offset such deficits. Mice were given varying doses of caffeine for 14 days and then deprived of sleep for 6 hours by the 'gentle handling' method. Memory was assessed using the Novel Object Recognition Test and Y maze alternation. The study was designed to ascertain the impact of varying doses of caffeine combined with total sleep-deprivation on spatial and non spatial memory in mice. Adult Swiss Webster mice of both sexes were assigned to six groups viz., vehicle (distilled water), or one of five selected doses of caffeine (10, 20, 40, 80 and 120 mg/kg) for 14 days via the oral route. Open field novel object recognition test and Y maze spatial working memory tests were carried out on day 14. Results were analysed using multi-factorial ANOVA followed by Tukey HSD test and expressed as mean ± S.E.M, with p values less than 0.05 were considered statistically significant. Novel object recognition tests (NOR) revealed that pre-training and pre-test sleep deprivation and caffeine combination impaired non spatial and spatial memory in male and female mice. The study shows the complex interactions with memory that may arise when total sleep deprivation is superimposed on caffeine administration.

A Randomized, Two-Way Crossover Study to Evaluate the Pharmacokinetics of Caffeine Delivered Using Caffeinated Chewing Gum Versus a Marketed Caffeinated Beverage in Healthy Adult Volunteers.

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Sadek, Paul; Pan, Xiao; Shepherd, Phil; Malandain, Elise; Carney, John; Coleman, Hugh

2017-12-01

Background: This study was conducted to compare the pharmacokinetics of caffeine delivered using caffeinated chewing gum to that delivered using a marketed caffeinated beverage (instant coffee) in 16 healthy adult volunteers. Materials and Methods: This was a controlled open-label, randomized, two-period crossover study. Caffeinated chewing gum and a serving of instant coffee, each containing ∼50 mg caffeine, were administered with blood samples collected before and up to 24 hours after administration starts. Plasma caffeine levels were analyzed using validated liquid chromatography coupled with tandem mass spectrometry methodology. Results: There were no statistical differences between the two caffeine products in t max ( p  = 0.3308) and k a ( p  = 0.3894). Although formulated at ∼50 mg caffeine each, mean dose released from chewing gum was ∼18% less than beverage. Dose-normalized area under the concentration-time curve (AUC) 0-t , AUC 0-∞ , and C max was similar between products. Although the criteria were not set a priori and the study was not powered for concluding bioequivalence, the 90% confidence intervals fell within the bioequivalence limit of 80% to 125%. Conclusions: Existing scientific literature on caffeine, based mostly on data from caffeinated beverages, can be leveraged to support the safety of caffeine delivered by chewing gum and current maximum safe caffeine dose advice should be applicable irrespective of delivery method.

Caffeine induces high expression of cyp-35A family genes and inhibits the early larval development in Caenorhabditis elegans.

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Min, Hyemin; Kawasaki, Ichiro; Gong, Joomi; Shim, Yhong-Hee

2015-03-01

Intake of caffeine during pregnancy can cause retardation of fetal development. Although the significant influence of caffeine on animal development is widely recognized, much remains unknown about its mode of action because of its pleiotropic effects on living organisms. In the present study, by using Caenorhabditis elegans as a model organism, the effects of caffeine on development were examined. Brood size, embryonic lethality, and percent larval development were investigated, and caffeine was found to inhibit the development of C. elegans at most of the stages in a dosage-dependent fashion. Upon treatment with 30 mM caffeine, the majority (86.1 ± 3.4%) of the L1 larvae were irreversibly arrested without further development. In contrast, many of the late-stage larvae survived and grew to adults when exposed to the same 30 mM caffeine. These results suggest that early-stage larvae are more susceptible to caffeine than later-stage larvae. To understand the metabolic responses to caffeine treatment, the levels of expression of cytochrome P450 (cyp) genes were examined with or without caffeine treatment using comparative micro-array, and it was found that the expression of 24 cyp genes was increased by more than 2-fold (p family was the most prominent. Interestingly, depletion of the cyp-35A family genes one-by-one or in combination through RNA interference resulted in partial rescue from early larval developmental arrest caused by caffeine treatment, suggesting that the high-level induction of cyp-35A family genes can be fatal to the development of early-stage larvae.

Caffeine-Related Deaths: Manner of Deaths and Categories at Risk.

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Cappelletti, Simone; Piacentino, Daria; Fineschi, Vittorio; Frati, Paola; Cipolloni, Luigi; Aromatario, Mariarosaria

2018-05-14

Caffeine is the most widely consumed psychoactive compound worldwide. It is mostly found in coffee, tea, energizing drinks and in some drugs. However, it has become really easy to obtain pure caffeine (powder or tablets) on the Internet markets. Mechanisms of action are dose-dependent. Serious toxicities such as seizure and cardiac arrhythmias, seen with caffeine plasma concentrations of 15 mg/L or higher, have caused poisoning or, rarely, death; otherwise concentrations of 3⁻6 mg/kg are considered safe. Caffeine concentrations of 80⁻100 mg/L are considered lethal. The aim of this systematic review, performed following the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) statement for the identification and selection of studies, is to review fatal cases in which caffeine has been recognized as the only cause of death in order to identify potential categories at risk. A total of 92 cases have been identified. These events happened more frequently in infants, psychiatric patients, and athletes. Although caffeine intoxication is relatively uncommon, raising awareness about its lethal consequences could be useful for both clinicians and pathologists to identify possible unrecognized cases and prevent related severe health conditions and deaths.

Caffeine Increases Work Done above Critical Power, but Not Anaerobic Work.

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Silveira, Rodrigo; Andrade-Souza, Victor Amorim; Arcoverde, Lucyana; Tomazini, Fabiano; Sansonio, André; Bishop, David John; Bertuzzi, Romulo; Lima-Silva, Adriano Eduardo

2018-01-01

The assumption that the curvature constant (W') of the power-duration relationship represents anaerobic work capacity is a controversial, unresolved question. We investigated if caffeine ingestion could increase total work done above critical power (CP), and if this would be accompanied by greater anaerobic energy expenditure and by an enhanced maintenance of maximal oxidative metabolic rate. Nine men (26.6 ± 5.3 yr, V˙O2max 40.6 ± 5.8 mL·kg·min) cycled until exhaustion at different exercise intensities on different days to determine the CP and W'. On separated days, participants cycled until exhaustion in the severe-intensity domain (136% ± 7% of CP) after ingesting either caffeine (5 mg·kg body mass) or a placebo. Time to exhaustion was 34% longer with caffeine compared with placebo, and this was accompanied by a greater work done above CP (23.7 ± 5.7 vs 17.5 ± 3.6 kJ; 130% ± 30% vs 95% ± 14% of W', P Caffeine increased the aerobic energy expenditure (296.4 ± 91.0 vs 210.2 ± 71.9 kJ, P caffeine, but the V˙O2 end was similar between conditions and was not different from V˙O2max. Caffeine did not change time to reach V˙O2max but increased time maintained at V˙O2max (199.3 ± 105.9 vs 111.9 ± 87.1 s, P Caffeine increased total work done above CP, but this was not associated with greater anaerobic work. Rather, this was associated with a higher tolerance to maintain exercise at maximal oxidative metabolic rate.

Caffeine Confusion

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... 20 mg* Milk chocolate 1 ounce 6 mg* Cocoa beverage 5 ounces 4 mg* Chocolate milk beverage 8 ounces 5 mg* Cold relief medication 1 tablet 30 mg* *This is an average amount of caffeine. That means some of these products may contain a little more caffeine; some may ...

Caffeine in the milk prevents respiratory disorders caused by in utero caffeine exposure in rats.

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Bodineau, Laurence; Saadani-Makki, Fadoua; Jullien, Hugues; Frugière, Alain

2006-01-25

Consequences of postnatal caffeine exposure by the milk on ponto-medullary respiratory disturbances observed following an in utero caffeine exposure were analysed. Ponto-medullary-spinal cord preparations from newborn rats exposed to caffeine during gestation but not after the birth display an increase in respiratory frequency and an exaggeration of the hypoxic respiratory depression compared to not treated preparations. These data suggest that tachypneic and apneic episodes encountered in human newborns whose mother consumed caffeine during pregnancy are due in large part to central effect of caffeine at the ponto-medullary level. Both baseline respiratory frequency increase and emphasis of hypoxic respiratory depression are not encountered if rat dams consumed caffeine during nursing. Our hypothesis is that newborn rats exposed to caffeine during gestation but not after the birth would be in withdrawal situation whereas, when caffeine is present in drinking fluid of lactating dams, it goes down the milk and is able to prevent ponto-medullary respiratory disturbances.

Degradation of exogenous caffeine by Populus alba and its effects on endogenous caffeine metabolism.

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Pierattini, Erika C; Francini, Alessandra; Raffaelli, Andrea; Sebastiani, Luca

2016-04-01

This is the first study reporting the presence of endogenous caffeine, theobromine, and theophylline in all organs of poplar plants. Liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) was used in order to evaluate the uptake, translocation, and metabolism of caffeine-(trimethyl-(13)C) in Populus alba L. Villafranca clone grown in hydroponic conditions. We investigated the remediation of caffeine since it is one of the most widely consumed drugs and it is frequently detected in wastewater treatment plant effluents, surface water, and groundwater worldwide. Our results demonstrated that poplar can absorb and degrade exogenous caffeine without negative effects on plant health. Data showed that concentrations of all endogenous compounds varied depending on caffeine-(trimethyl-(13)C) treatments. In particular, in control conditions, endogenous caffeine, theobromine, and theophylline were mainly distributed in roots. On the other hand, once caffeine-(trimethyl-(13)C) was provided, this compound and its dimethy-(13)C metabolites are mainly localized at leaf level. In conclusion, our results support the possible use of Villafranca clone in association with other water treatment systems in order to complete the process of caffeine remediation.

Evaluating Dependence Criteria for Caffeine.

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Striley, Catherine L W; Griffiths, Roland R; Cottler, Linda B

2011-12-01

Background: Although caffeine is the most widely used mood-altering drug in the world, few studies have operationalized and characterized Diagnostic and Statistical Manual IV (DSM-IV) substance dependence criteria applied to caffeine. Methods: As a part of a nosological study of substance use disorders funded by the National Institute on Drug Abuse, we assessed caffeine use and dependence symptoms among high school and college students, drug treatment patients, and pain clinic patients who reported caffeine use in the last 7 days and also reported use of alcohol, nicotine, or illicit drugs within the past year ( n =167). Results: Thirty-five percent met the criteria for dependence when all seven of the adopted DSM dependence criteria were used. Rates of endorsement of several of the most applicable diagnostic criteria were as follows: 26% withdrawal, 23% desire to cut down or control use, and 44% continued use despite harm. In addition, 34% endorsed craving, 26% said they needed caffeine to function, and 10% indicated that they talked to a physician or counselor about problems experienced with caffeine. There was a trend towards increased caffeine dependence among those dependent on nicotine or alcohol. Within a subgroup that had used caffeine, alcohol, and nicotine in the past year, 28% fulfilled criteria for caffeine dependence compared to 50% for alcohol and 80% for nicotine. Conclusion: The present study adds to a growing literature suggesting the reliability, validity, and clinical utility of the caffeine dependence diagnosis. Recognition of caffeine dependence in the DSM-V may be clinically useful.

Caffeine and theobromine in epicuticular wax of Ilex paraguariensis A. St.-Hil.

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Athayde, M L; Coelho, G C; Schenkel, E P

2000-12-01

Caffeine and theobromine were identified and quantified in leaf epicuticular waxes of Ilex paraguariensis A. St.-Hil. (Aquifoliaceae). The total epicuticular leaf wax content was ca. 0.5% on average of dry leaf weight. Epicuticular caffeine and theobromine contents varied from 0.16 to 127.6 microg/mg and from 0 to 9.5 microg/mg of wax, respectively. For some selected samples, the intracellular methylxanthine concentration was also determined. A positive correlation was found between inner and epicuticular caffeine contents.

Spectrophotometric Analysis of Caffeine

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Showkat Ahmad Bhawani

2015-01-01

Full Text Available The nature of caffeine reveals that it is a bitter white crystalline alkaloid. It is a common ingredient in a variety of drinks (soft and energy drinks and is also used in combination with various medicines. In order to maintain the optimum level of caffeine, various spectrophotometric methods have been developed. The monitoring of caffeine is very important aspect because of its consumption in higher doses that can lead to various physiological disorders. This paper incorporates various spectrophotometric methods used in the analysis of caffeine in various environmental samples such as pharmaceuticals, soft and energy drinks, tea, and coffee. A range of spectrophotometric methodologies including chemometric techniques and derivatization of spectra have been used to analyse the caffeine.

Caffeine alleviates progressive motor deficits in a transgenic mouse model of spinocerebellar ataxia.

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Gonçalves, Nélio; Simões, Ana T; Prediger, Rui D; Hirai, Hirokazu; Cunha, Rodrigo A; Pereira de Almeida, Luís

2017-03-01

Machado-Joseph disease (MJD) is a neurodegenerative spinocerebellar ataxia (SCA) associated with an expanded polyglutamine tract within ataxin-3 for which there is currently no available therapy. We previously showed that caffeine, a nonselective adenosine receptor antagonist, delays the appearance of striatal damage resulting from expression of full-length mutant ataxin-3. Here we investigated the ability of caffeine to alleviate behavioral deficits and cerebellar neuropathology in transgenic mice with a severe ataxia resulting from expression of a truncated fragment of polyglutamine-expanded ataxin-3 in Purkinje cells. Control and transgenic c57Bl6 mice expressing in the mouse cerebella a truncated form of human ataxin-3 with 69 glutamine repeats were allowed to freely drink water or caffeinated water (1g/L). Treatments began at 7 weeks of age, when motor and ataxic phenotype emerges in MJD mice, and lasted up to 20 weeks. Mice were tested in a panel of locomotor behavioral paradigms, namely rotarod, beam balance and walking, pole, and water maze cued-platform version tests, and then sacrificed for cerebellar histology. Caffeine consumption attenuated the progressive loss of general and fine-tuned motor function, balance, and grip strength, in parallel with preservation of cerebellar morphology through decreasing the loss of Purkinje neurons and the thinning of the molecular layer in different folia. Caffeine also rescued the putative striatal-dependent executive and cognitive deficiencies in MJD mice. Our findings provide the first in vivo demonstration that caffeine intake alleviates behavioral disabilities in a severely impaired animal model of SCA. Ann Neurol 2017;81:407-418. © 2016 American Neurological Association.

Effects of acute caffeine withdrawal on Short Category Test performance in sleep-deprived individuals.

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Killgore, William D S; Kahn-Greene, Ellen T; Killgore, Desiree B; Kamimori, Gary H; Balkin, Thomas J

2007-12-01

Caffeine is a popular stimulant often used to counter the effects of sleep loss and fatigue. Withdrawal from caffeine may produce mild declines in simple cognitive capacities such as attention and concentration, but it is unclear whether more complex cognitive functions, such as abstract reasoning or concept formation, may be similarly affected. To assess the effect of acute caffeine withdrawal on executive functioning during sleep deprivation, 26 healthy volunteers were administered in double-blind form either repeated doses of caffeine or placebo over two nights of continuous wakefulness. The 108-item Short Category Test was administered after 56 hr. of total sleep deprivation (9 hr. post-caffeine administration). The caffeine group scored significantly more poorly, making approximately 57% more errors on the test than the placebo group. These findings suggest that acute caffeine withdrawal during prolonged sleep deprivation has an adverse effect on abstract reasoning and concept formation.

Caffeine and REM sleep deprivation: Effect on basal levels of signaling molecules in area CA1.

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Alkadhi, Karim A; Alhaider, Ibrahim A

2016-03-01

We have investigated the neuroprotective effect of chronic caffeine treatment on basal levels of memory-related signaling molecules in area CA1 of sleep-deprived rats. Animals in the caffeine groups were treated with caffeine in drinking water (0.3g/l) for four weeks before they were REM sleep-deprived for 24h in the Modified Multiple Platforms paradigm. Western blot analysis of basal protein levels of plasticity- and memory-related signaling molecules in hippocampal area CA1 showed significant down regulation of the basal levels of phosphorylated- and total-CaMKII, phosphorylated- and total-CREB as well as those of BDNF and CaMKIV in sleep deprived rats. All these changes were completely prevented in rats that chronically consumed caffeine. The present findings suggest an important neuroprotective property of caffeine in sleep deprivation. Copyright © 2016 Elsevier Inc. All rights reserved.

Caffeine supplementation improves countermovement jump in youth soccer players: a pilot study

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Juan Diego Hernández-Camacho

2017-07-01

Full Text Available Introduction: The objective of this study was to analyze the effect of caffeine ingestion in soccer performance, particularly in the countermovement jump test (CMJ. Material and methods: A total of 17 players from a U-19 amateur Spanish team participated in this pilot study. A double-blind placebo-controlled randomized experimental design was used in 2 different sessions (1.5 hour per session separated by 1 week. CMJ was collected at the beginning and at the end of sessions; Rating of Perceived Exertion (RPE was recorded. Players ingested caffeine or placebo at the beginning of session (minute 0 of session, providing a total of 4 mg of caffeine or a placebo per kg of body mass. Side effects from caffeine and placebo ingestions were analyzed. The effect sizes (ES were calculated using values for Cohen’s and Quantitative differences were assessed qualitatively (QA. Results: The jump height with caffeine supplementation at the beginning of training was 37.03 (±3.87 cm and at the end was 39.35 (±4.05 cm, obtaining significant improvements (p<0.05; ES: 0.56; QA: 99/1/0. Significant differences on CMJ at the end of the training session between caffeine and placebo groups were observed (39.35 [±4.05] cm vs. 36.85 [±3.15] cm; p<0.05; ES: 0.65; QA: 0/1/99. Significant differences on RPE between groups were observed. A non-significant tendency to suffer more side effects with caffeine ingestion was obtained. Conclusions: This study shows how the ingestion of 4 mg of caffeine per kg of body mass could be an ergogenic aid to improve soccer performance. However, further studies with bigger soccer players sample would be necessary to refute the present results.

Caffeine Affects Time to Exhaustion and Substrate Oxidation during Cycling at Maximal Lactate Steady State

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Rogério Santos de Oliveira Cruz

2015-06-01

Full Text Available This study analyzed the effects of caffeine intake on whole-body substrate metabolism and exercise tolerance during cycling by using a more individualized intensity for merging the subjects into homogeneous metabolic responses (the workload associated with the maximal lactate steady state—MLSS. MLSS was firstly determined in eight active males (25 ± 4 years, 176 ± 7 cm, 77 ± 11 kg using from two to four constant-load tests of 30 min. On two following occasions, participants performed a test until exhaustion at the MLSS workload 1 h after taking either 6 mg/kg of body mass of caffeine or placebo (dextrose, in a randomized, double-blinded manner. Respiratory exchange ratio was calculated from gas exchange measurements. There was an improvement of 22.7% in time to exhaustion at MLSS workload following caffeine ingestion (95% confidence limits of ±10.3%, p = 0.002, which was accompanied by decrease in respiratory exchange ratio (p = 0.001. These results reinforce findings indicating that sparing of the endogenous carbohydrate stores could be one of the several physiological effects of caffeine during submaximal performance around 1 h.

Caffeine Consumption among Medical Interns and Association with GPA in Makkah Region

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Alsharif Mohammed H

2016-12-01

Full Text Available The Vagarious amount of caffeine may become harmful in frequent use, it increased among medical interns in Makkah region. The caffeine becomes a daily routine for medical interns without attention for their side harmful effect. The purpose of our study was to evaluate the educational level of awareness of the harmful effect of caffeine consumption. This was a cross-sectional study from August to October 2016. A total number 437 of participants with GPA groups, Group I (GPA 1.5-2, Group II (GPA 2.1- 3 and Group III (GPA 3.1- 3.5. The higher percentages were the group II and female consumed caffeine frequently more than male.

Caffeine for asthma

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Welsh, EJ; Bara, A; Barley, E; Cates, CJ

2010-01-01

Background\\ud \\ud Caffeine has a variety of pharmacological effects; it is a weak bronchodilator and it also reduces respiratory muscle fatigue. It is chemically related to the drug theophylline which is used to treat asthma. It has been suggested that caffeine may reduce asthma symptoms and interest has been expressed in its potential role as an asthma treatment. A number of studies have explored the effects of caffeine in asthma, this is the first review to systematically examine and summar...

Carcinogenic and neurotoxic risks of acrylamide consumed through caffeinated beverages among the lebanese population.

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El-Zakhem Naous, Ghada; Merhi, Areej; Abboud, Martine I; Mroueh, Mohamad; Taleb, Robin I

2018-06-06

The present study aims to quantify acrylamide in caffeinated beverages including American coffee, Lebanese coffee, espresso, instant coffee and hot chocolate, and to determine their carcinogenic and neurotoxic risks. A survey was carried for this purpose whereby 78% of the Lebanese population was found to consume at least one type of caffeinated beverages. Gas Chromatography Mass Spectrometry analysis revealed that the average acrylamide level in caffeinated beverages is 29,176 μg/kg sample. The daily consumption of acrylamide from Lebanese coffee (10.9 μg/kg-bw/day), hot chocolate (1.2 μg/kg-bw/day) and Espresso (7.4 μg/kg-bw/day) was found to be higher than the risk intake for carcinogenicity and neurotoxicity as set by World Health Organization (WHO; 0.3-2 μg/kg-bw/day) at both the mean (average consumers) and high (high consumers) dietary exposures. On the other hand, American coffee (0.37 μg/kg-bw/day) was shown to pose no carcinogenic or neurotoxic risks among the Lebanese community for consumers with a mean dietary exposure. The study shows alarming results that call for regulating the caffeinated product industry by setting legislations and standard protocols for product preparation in order to limit the acrylamide content and protect consumers. In order to avoid carcinogenic and neurotoxic risks, we propose that WHO/FAO set acrylamide levels in caffeinated beverages to 7000 μg acrylamide/kg sample, a value which is 4-folds lower than the average acrylamide levels of 29,176 μg/kg sample found in caffeinated beverages sold in the Lebanese market. Alternatively, consumers of caffeinated products, especially Lebanese coffee and espresso, would have to lower their daily consumption to 0.3-0.4 cups/day. Copyright © 2018 Elsevier Ltd. All rights reserved.

Caffeine in Pregnancy

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... Global Map Premature Birth Report Cards Careers Archives Pregnancy Before or between pregnancies Nutrition, weight & fitness Prenatal ... Nutrition, weight & fitness > Caffeine in pregnancy Caffeine in pregnancy E-mail to a friend Please fill in ...

Adsorption behavior of caffeine as a green corrosion inhibitor for copper

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Souza, Fernando Sílvio de; Giacomelli, Cristiano; Gonçalves, Reinaldo Simões; Spinelli, Almir

2012-01-01

Electrochemical and impedance experiments were carried out to evaluate the corrosion behavior of copper in aerated 0.1 mol L −1 H 2 SO 4 solutions in the presence of three xanthine derivatives with similar chemical structures. The corrosion rate of copper was found to increase in the presence of theophylline and theobromine and decrease in the presence of caffeine. The adsorption and inhibitory effect of caffeine on copper surfaces in aerated 0.1 mol L −1 H 2 SO 4 solutions were then investigated in detail by potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), contact angle measurements, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and fluorescence experiments. The data obtained indicate that caffeine behaves as a cathodic-type inhibitor adsorbing onto the copper surface according to the Temkin isotherm, with the negative ∆G° ads value of − 31.1 kJ mol −1 signifying a spontaneous adsorption process. The corrosion inhibition efficiency increased with caffeine concentration in the range of 1.0–10.0 mmol L −1 . Furthermore, the EIS results obtained at the open-circuit potential and surface analysis (SEM, EDS and fluorescence) clearly demonstrated the adsorption of the organic compound onto the copper electrode. The contact angle measurements revealed the formation of a hydrophobic protective film. This film covers up to 72% of the total active surface, acts as a protective barrier and prevents interaction between the metal, water and oxygen molecules. - Highlights: ► We have investigated the adsorption and corrosion inhibition of caffeine on copper surfaces. ► Caffeine behaves as a cathodic-type inhibitor. ► Caffeine adsorbs onto copper surface according to Temkin isotherm. ► There exists the formation of a hydrophobic film that acts as a protective barrier. ► This corrosion inhibitor covers up to 72% of the total active surface of copper.

Caffeine Use and Extroversion.

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Landrum, R. Eric; Meliska, Charles J.

Some research on the stimulant effect of caffeine suggests that the amount of behavioral enhancement produced by caffeine may depend on subjects' prior experience with the task and the drug. A study was undertaken to test whether prior experience with a task while under the influence of caffeine would facilitate performance of that task. Male…

Coffee, tea, and caffeine consumption and breast cancer incidence in a cohort of Swedish women.

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Michels, Karin B; Holmberg, Lars; Bergkvist, Leif; Wolk, Alicja

2002-01-01

Coffee, caffeinated tea, and caffeine have been suggested to play a role in breast carcinogenesis or in the promotion or inhibition of tumor growth. Prior epidemiologic evidence has not supported an overall association between consumption of caffeinated beverages and risk of breast cancer, but consumption in some studies was low. We studied this relation in the Swedish Mammography Screening Cohort, a large population-based prospective cohort study in Sweden comprising 59,036 women aged 40-76 years. Sweden has the highest coffee consumption per capita in the world. During 508,267 person-years of follow-up, 1271 cases of invasive breast cancer were diagnosed. Women who reported drinking 4 or more cups of coffee per day had a covariate-adjusted hazard ratio of breast cancer of 0.94 [95% confidence interval (CI) 0.75-1.28] compared to women who reported drinking 1 cup a week or less. The corresponding hazard ratio for tea consumption was 1.13 (95% CI 0.91-1.40). Similarly, women in the highest quintile of self-reported caffeine intake had a hazard ratio of beast cancer of 1.04 (95% CI 0.87-1.24) compared to women in the lowest quintile. In this large cohort of Swedish women, consumption of coffee, tea, and caffeine was not associated with breast cancer incidence.

Clinical importance of caffeine dependence and abuse.

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Ogawa, Naoshi; Ueki, Hirofumi

2007-06-01

Caffeine is the most widely consumed psychoactive substance and is a legal stimulant that is readily available to children. Caffeine has occasionally been considered a drug of abuse and the potential for dependence on caffeine has been debated. Presently, due to a paucity of clinical evidence on caffeine dependence or abuse, no such diagnosis is included in the Diagnostic and Statistical Manual of Mental Disorder-fourth edition. The authors present two cases of abuse or dependence on the caffeine contained in 'eutrophic' (energy/nutritional) beverages or caffeine preparations, followed by a review of clinical studies demonstrating evidence that some people can manifest a clinical syndrome of caffeine dependence or abuse. The cases suggest that caffeine can produce a clinical dependence syndrome similar to those produced by other psychoactive substances and has a potential for abuse. In a recent study using a structured interview and the Diagnostic and Statistical Manual of Mental Disorder-fourth edition criteria for substance dependence and abuse, a subset of the general population was found to demonstrate caffeine dependence or caffeine abuse. Therefore, the authors propose that companies or businesses manufacturing or marketing caffeine or products containing caffeine must meet the following guidelines: (i) clearly indicate the caffeine content of products containing comparatively higher quantities of caffeine; (ii) warn that such products should be avoided by infants and children wherever possible, and inform adult consumers about the precise quantity of caffeine that is considered safe for consumption; and (iii) clearly state that consuming large quantities of caffeine and the long-term use of caffeine carry health risks.

Caffeine as an indicator of human fecal contamination in the Sinos River: a preliminary study

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R Linden

Full Text Available The preservation of hydric resources is directly related to fecal contamination monitoring, in order to allow the development of strategies for the management of polluting sources. In the present study, twenty-five water samples from six water public supply collection sites were used for the evaluation of the presence of caffeine, total and fecal coliforms. Caffeine was detected in all samples, with concentrations ranging from 0.15 ng mL–1 to 16.72 ng mL–1. Total coliforms were detected in all samples, with concentrations in the range of 52 NMP/100 mL to higher than 24196 NMP/100 mL, whether the concentration range for fecal coliforms was in the range of below 1 NMP/100 mL to 7800 NMP/100 mL. No significant correlation was found between total coliforms and caffeine concentrations (rs = 0.35, p = 0.09. However, a moderate correlation between fecal coliforms and caffeine concentrations was found (rs = 0.412, p

Compound list: caffeine [Open TG-GATEs

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Full Text Available caffeine CAF 00097 ftp://ftp.biosciencedbc.jp/archive/open-tggates/LATEST/Human/in_vitro/caffeine....Human.in_vitro.Liver.zip ftp://ftp.biosciencedbc.jp/archive/open-tggates/LATEST/Rat/in_vitro/caffeine....Rat.in_vitro.Liver.zip ftp://ftp.biosciencedbc.jp/archive/open-tggates/LATEST/Rat/in_vivo/Liver/Single/caffeine...-tggates/LATEST/Rat/in_vivo/Liver/Repeat/caffeine.Rat.in_vivo.Liver.Repeat.zip ftp://ftp.biosciencedbc.jp/ar...chive/open-tggates/LATEST/Rat/in_vivo/Kidney/Single/caffeine.Rat.in_vivo.Kidney.Single.zip ftp://ftp.bioscie

Intake and total apparent digestibility in lambs fed six maize varieties in the Brazilian Semiarid

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Rafael Dantas dos Santos

2011-12-01

Full Text Available The objective of this study was to evaluate the daily intake and total apparent digestibility of dry matter, organic matter, crude protein, gross energy, ether extract, neutral detergent fiber, acid detergent fiber, total and non-fibrous carbohydrates, total digestible nutrients, energy intake and nitrogen balance of silages of six maize varieties with early or super early cycles recommended to Northeast Brazil. Twenty-four male castrated lambs were lodged in metabolic cages. A completely randomized design with six treatments and four replications was used, with means compared by Tukey test at 5%. There were no differences among varieties for any of the evaluated variables regarding intake and apparent digestibility. Concerning the intake of digestible energy, metabolizable energy and the ratio content of digestible and metabolizable energy, significant differences were observed between varieties and BRS Assum Preto showed highest values of metabolizable energy (2.650,8 kcal/day. All of the treatments presented positive nitrogen balance and did not differ among themselves. The varieties asessed can be an additional option to the semiarid regions in Brazil.

Altered expression of the caffeine synthase gene in a naturally caffeine-free mutant of Coffea arabica

Directory of Open Access Journals (Sweden)

Mirian Perez Maluf

2009-01-01

Full Text Available In this work, we studied the biosynthesis of caffeine by examining the expression of genes involved in this biosynthetic pathway in coffee fruits containing normal or low levels of this substance. The amplification of gene-specific transcripts during fruit development revealed that low-caffeine fruits had a lower expression of the theobromine synthase and caffeine synthase genes and also contained an extra transcript of the caffeine synthase gene. This extra transcript contained only part of exon 1 and all of exon 3. The sequence of the mutant caffeine synthase gene revealed the substitution of isoleucine for valine in the enzyme active site that probably interfered with enzymatic activity. These findings indicate that the absence of caffeine in these mutants probably resulted from a combination of transcriptional regulation and the presence of mutations in the caffeine synthase amino acid sequence.

Consumption of caffeinated beverages and the awareness of their caffeine content among Dutch students

NARCIS (Netherlands)

Mackus, Marlou; van de Loo, Aurora J A E; Benson, Sarah; Scholey, Andrew; Verster, Joris C

2016-01-01

The purpose of the current study was to examine the knowledge of caffeine content of a variety of caffeinated beverages among Dutch university students. A pencil-and-paper survey was conducted among N = 800 Dutch students. Most participants (87.8%) reported consuming caffeinated beverages during the

Caffeine Content of Tea and Coffee

African Journals Online (AJOL)

1974-03-13

Mar 13, 1974 ... The xanthines (caffeine, theophylline, and theobromine) occur in plants widely distributed throughout the world. Best known for the preparation of beverages are coffee beans which contain caffeine, tea leaves which contain caffeine and theophylline, and cocoa seeds which contain caffeine and ...

Coffee intake, cardiovascular disease and allcause mortality

DEFF Research Database (Denmark)

Nordestgaard, Ask Tybjærg; Nordestgaard, Børge Grønne

2016-01-01

Background: Coffee has been associated with modestly lower risk of cardiovascular disease and all-cause mortality in meta-analyses; however, it is unclear whether these are causal associations. We tested first whether coffee intake is associated with cardiovascular disease and all-cause mortality...... observationally; second, whether genetic variations previously associated with caffeine intake are associated with coffee intake; and third, whether the genetic variations are associated with cardiovascular disease and all-cause mortality. Methods: First, we used multivariable adjusted Cox proportional hazard......- and age adjusted Cox proportional hazard regression models to examine genetic associations with cardiovascular disease and all-cause mortality in 112 509 Danes. Finally, we used sex and age-adjusted logistic regression models to examine genetic associations with ischaemic heart disease including...

Synergism between caffeine and γ-radiation in the induction of dominant lethal mutations in oocytes and spermatozoa of Musca domestica

International Nuclear Information System (INIS)

Targa, H.J.

1983-01-01

Caffeine was studied with regard to its synergism with γ-radiation in the induction of dominant lethal mutations in S14 oocytes and mature spermatozoa of M. domestica. In S14 oocytes an increase in the frequency of such a type of mutation was observed only when the exposure to γ-radiation followed a pretreatment with a diet containing 0.2% of caffeine. Negative results were obtained with (a) post-treatment with the same kind of diet, (b) pretreatment with diets containing 0.1 and 0.02% of caffeine and (c) exposure to the radiation 6 h after interruption of the feeding treatment with the diet containing 0.2% of caffeine. Such influence of the conditions under which the treatment is performed and the synergistic effects is probably related to the food intake pattern and the rapid metabolism of the caffeine. When the 0.2% caffeine pretreatment was combined with an exposure of the oocytes to variable doses of γ-radiation, the increments in the mutations observed seemed to be negatively correlated to the radiation doses used. Also, under such conditions, the dose/survival relationship fits well an exponential curve expressed by in y=-0.866chi. With mature spermatozoa, synergism by caffeine was found only when the females, after having been mated with the irradiated males, were fed for 24 h on a diet supplemented with 0.2% of caffeine. (orig.)

Heritability of caffeine metabolism

DEFF Research Database (Denmark)

Matthaei, Johannes; Tzvetkov, Mladen V; Strube, Jakob

2016-01-01

Heritability of caffeine pharmacokinetics and CYP1A2 activity is controversial. Here we analyzed the pharmacokinetics of caffeine, an in vivo probe drug for CYP1A2 and arylamine N-acetyltransferase 2 (NAT2) activity, in monozygotic and dizygotic twins. In the entire group, common and unique...... environmental effects explained most variation in caffeine AUC. Apparently, smoking and hormonal contraceptives masked the genetic effects on CYP1A2 activity. However, when excluding smokers and users of hormonal contraceptives, 89% of caffeine AUC variation was due to genetic effects and even in the entire...... group, 8% of caffeine AUC variation could be explained by a CYP1A1/1A2 promotor polymorphism (rs2470893). In contrast, nearly all of the variation (99%) of NAT2 activity was explained by genetic effects. This study illustrates two very different situations in pharmacogenetics, from an almost exclusively...

Caffeine-induced increase in voluntary activation and strength of the quadriceps muscle during isometric, concentric and eccentric contractions.

Science.gov (United States)

Behrens, Martin; Mau-Moeller, Anett; Weippert, Matthias; Fuhrmann, Josefin; Wegner, Katharina; Skripitz, Ralf; Bader, Rainer; Bruhn, Sven

2015-05-13

This study investigated effects of caffeine ingestion (8 mg/kg) on maximum voluntary torque (MVT) and voluntary activation of the quadriceps during isometric, concentric and eccentric contractions. Fourteen subjects ingested caffeine and placebo in a randomized, controlled, counterbalanced, double-blind crossover design. Neuromuscular tests were performed before and 1 h after oral caffeine and placebo intake. MVTs were measured and the interpolated twitch technique was applied during isometric, concentric and eccentric contractions to assess voluntary activation. Furthermore, normalized root mean square of the EMG signal was calculated and evoked spinal reflex responses (H-reflex evoked at rest and during weak isometric voluntary contraction) as well as twitch torques were analyzed. Caffeine increased MVT by 26.4 N m (95%CI: 9.3-43.5 N m, P = 0.004), 22.5 N m (95%CI: 3.1-42.0 N m, P = 0.025) and 22.5 N m (95%CI: 2.2-42.7 N m, P = 0.032) for isometric, concentric and eccentric contractions. Strength enhancements were associated with increases in voluntary activation. Explosive voluntary strength and voluntary activation at the onset of contraction were significantly increased following caffeine ingestion. Changes in spinal reflex responses and at the muscle level were not observed. Data suggest that caffeine ingestion induced an acute increase in voluntary activation that was responsible for the increased strength regardless of the contraction mode.

CORRELATION BETWEEN CAFFEINE CONTENTS OF GREEN ...

African Journals Online (AJOL)

KEY WORDS: Green coffee beans, Caffeine, Correlation between caffeine content and altitude of coffee plant,. UV-Vis .... The extraction of caffeine from green coffee bean samples in to water was carried out by the reported method ..... caffeine in proposed green tea standard reference materials by liquid chromatography.

Effects of caffeine on alcohol-related changes in behavioural control and perceived intoxication in light caffeine consumers.

Science.gov (United States)

Attwood, Angela S; Rogers, Peter J; Ataya, Alia F; Adams, Sally; Munafò, Marcus R

2012-06-01

Caffeinated alcoholic beverages have been associated with increased risk of alcohol-related harms. However, few studies have examined these combined effects on behavioural control, which is believed to underlie many of the negative effects of alcohol consumption. In addition, studies have often omitted subjective measures, and none have directly assessed the role of caffeine consumer history. To examine the combined effects of alcohol and caffeine on measures of behavioural control and perceived intoxication in abstinent, light caffeine consumers. Participants (n = 28; 50% male) attended four sessions at which they consumed one of the following beverages in a randomised order: placebo, alcohol alone (0.6 g/kg), caffeine alone (2.0 mg/kg), and alcohol/caffeine. They completed measures of mood, intoxication, anxiety and alcohol craving before and after a task battery comprising measures of behavioural control and reaction time performance. Caffeine attenuated alcohol-related performance deficits on stop-signal accuracy, had no effect on go-no-go performance deficits, and worsened accuracy on the Stroop task. Caffeine did not influence absolute changes in perceived intoxication but there was suggestion that caffeine may have changed the nature of intoxication with increases in stimulation. Caffeine appears to have mixed effects on alcohol intoxication that are task-dependent. We found increased stimulation in the alcohol/caffeine condition, supporting the contention that caffeinated alcoholic beverages enable an individual to drink for longer. Future research should model real world drinking behaviour by examining how these effects change across multiple drink administrations.

Caffeine withdrawal and high-intensity endurance cycling performance.

Science.gov (United States)

Irwin, Christopher; Desbrow, Ben; Ellis, Aleisha; O'Keeffe, Brooke; Grant, Gary; Leveritt, Michael

2011-03-01

In this study, we investigated the impact of a controlled 4-day caffeine withdrawal period on the effect of an acute caffeine dose on endurance exercise performance. Twelve well-trained and familiarized male cyclists, who were caffeine consumers (from coffee and a range of other sources), were recruited for the study. A double-blind placebo-controlled cross-over design was employed, involving four experimental trials. Participants abstained from dietary caffeine sources for 4 days before the trials and ingested capsules (one in the morning and one in the afternoon) containing either placebo or caffeine (1.5 mg · kg(-1) body weight · day(-1)). On day 5, capsules containing placebo or caffeine (3 mg · kg(-1) body weight) were ingested 90 min before completing a time trial, equivalent to one hour of cycling at 75% peak sustainable power output. Hence the study was designed to incorporate placebo-placebo, placebo-caffeine, caffeine-placebo, and caffeine-caffeine conditions. Performance time was significantly improved after acute caffeine ingestion by 1:49 ± 1:41 min (3.0%, P = 0.021) following a withdrawal period (placebo-placebo vs. placebo-caffeine), and by 2:07 ± 1:28 min (3.6%, P = 0.002) following the non-withdrawal period (caffeine-placebo vs. caffeine-caffeine). No significant difference was detected between the two acute caffeine trials (placebo-caffeine vs. caffeine-caffeine). Average heart rate throughout exercise was significantly higher following acute caffeine administration compared with placebo. No differences were observed in ratings of perceived exertion between trials. A 3 mg · kg(-1) dose of caffeine significantly improves exercise performance irrespective of whether a 4-day withdrawal period is imposed on habitual caffeine users.

Increase in cocaine- and amphetamine-regulated transcript (CART) in specific areas of the mouse brain by acute caffeine administration.

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Cho, Jin Hee; Cho, Yun Ha; Kim, Hyo Young; Cha, Seung Ha; Ryu, Hyun; Jang, Wooyoung; Shin, Kyung Ho

2015-04-01

Caffeine produces a variety of behavioral effects including increased alertness, reduced food intake, anxiogenic effects, and dependence upon repeated exposure. Although many of the effects of caffeine are mediated by its ability to block adenosine receptors, it is possible that other neural substrates, such as cocaine- and amphetamine-regulated transcript (CART), may be involved in the effects of caffeine. Indeed, a recent study demonstrated that repeated caffeine administration increases CART in the mouse striatum. However, it is not clear whether acute caffeine administration alters CART in other areas of the brain. To explore this possibility, we investigated the dose- and time-dependent changes in CART immunoreactivity (CART-IR) after a single dose of caffeine in mice. We found that a high dose of caffeine (100 mg/kg) significantly increased CART-IR 2 h after administration in the nucleus accumbens shell (AcbSh), dorsal bed nucleus of the stria terminalis (dBNST), central nucleus of the amygdala (CeA), paraventricular hypothalamic nucleus (PVN), arcuate hypothalamic nucleus (Arc), and locus coeruleus (LC), and returned to control levels after 8 h. But this increase was not observed in other brain areas. In addition, caffeine administration at doses of 25 and 50 mg/kg appears to produce dose-dependent increases in CART-IR in these brain areas; however, the magnitude of increase in CART-IR observed at a dose of 50 mg/kg was similar or greater than that observed at a dose of 100 mg/kg. This result suggests that CART-IR in AcbSh, dBNST, CeA, PVN, Arc, and LC is selectively affected by caffeine administration. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effects of caffeine on locomotor activity in streptozotocin-induced diabetic rats.

Science.gov (United States)

Bădescu, S V; Tătaru, C P; Kobylinska, L; Georgescu, E L; Zahiu, D M; Zăgrean, A M; Zăgrean, L

2016-01-01

Diabetes mellitus modifies the expression of adenosine receptors in the brain. Caffeine acts as an antagonist of A1 and A2A adenosine receptors and was shown to have a dose-dependent biphasic effect on locomotion in mice. The present study investigated the link between diabetes and locomotor activity in an animal model of streptozotocin-induced diabetes, and the effects of a low-medium dose of caffeine in this relation. The locomotor activity was investigated by using Open Field Test at 6 weeks after diabetes induction and after 2 more weeks of chronic caffeine administration. Diabetes decreased locomotor activity (total distance moved and mobility time). Chronic caffeine exposure impaired the locomotor activity in control rats, but not in diabetic rats. Our data suggested that the medium doses of caffeine might block the A2A receptors, shown to have an increased density in the brain of diabetic rats, and improve or at least maintain the locomotor activity, offering a neuroprotective support in diabetic rats. Abbreviations : STZ = streptozotocin, OFT = Open Field Test.

Effects of p-Synephrine and Caffeine Ingestion on Substrate Oxidation during Exercise.

Science.gov (United States)

Gutiérrez-Hellín, Jorge; Del Coso, Juan

2018-04-27

Caffeine and p-synephrine are substances usually included in commercially-available products for weight loss because of their purported thermogenic effects. However, scientific information is lacking about the effects of combining these substances on substrate oxidation during exercise. The purpose of this investigation was to determine the isolated and combined effects of p-synephrine and caffeine on fat oxidation rate during exercise. In a double-blind randomized experiment, 13 healthy subjects participated in 4 experimental trials after the ingestion of a capsule containing either a placebo, 3 mg·kg of caffeine, 3 mg·kg of p-synephrine, or the combination of these doses of caffeine and p-synephrine. Energy expenditure and substrate oxidation rates were measured by indirect calorimetry during a cycle ergometer ramp test from 30 to 90% of VO2max. In comparison to the placebo, the ingestion of caffeine, p-synephrine, or p-synephrine+caffeine did not alter total energy expenditure or heart rate during the whole exercise test. However, the ingestion of caffeine (0.44 ± 0.15 g·min, P = 0.03), p-synephrine (0.43 ± 0.19 g·min, P < 0.01), and p-synephrine+caffeine (0.45 ± 0.15 g·min, P = 0.02) increased the maximal rate of fat oxidation during exercise when compared to the placebo (0.30 ± 0.12 g·min). The exercise intensity that elicited maximal fat oxidation was similar in all trials (~46.2 ± 10.2% of VO2max). Caffeine, p-synephrine and p-synephrine+caffeine increased the maximal rate of fat oxidation during exercise compared to a placebo, without modifying energy expenditure or heart rate. However, the co-ingestion of p-synephrine and caffeine did not present an additive effect to further increase fat oxidation during exercise.

Smoking, caffeine, and nonsteroidal anti-inflammatory drugs in families with Parkinson disease.

Science.gov (United States)

Hancock, Dana B; Martin, Eden R; Stajich, Jeffrey M; Jewett, Rita; Stacy, Mark A; Scott, Burton L; Vance, Jeffery M; Scott, William K

2007-04-01

To assess associations between Parkinson disease (PD) and putatively protective factors-smoking, caffeine (coffee, tea, and soft drinks), and nonsteroidal anti-inflammatory drugs (aspirin, ibuprofen, and naproxen). Family-based case-control study. Academic medical center clinic. A total of 356 case subjects and 317 family controls who self-reported environmental exposures. Associations between PD and environmental measures (history, status, dosage, duration, and intensity) of smoking, coffee, caffeine, nonsteroidal anti-inflammatory drugs, and non-aspirin nonsteroidal anti-inflammatory drugs were examined using generalized estimating equations with an independent correlation matrix while controlling for age and sex. Individuals with PD were significantly less likely to report ever smoking (odds ratio = 0.56; 95% confidence interval, 0.41-0.78). Additional measures of smoking revealed significant inverse associations with PD (Pcoffee drinking was inversely associated with PD (test for trend P = .05). Increasing dosage (trend P = .009) and intensity (trend P = .01) of total caffeine consumption were also inversely associated, with high dosage presenting a significant inverse association for PD (odds ratio = 0.58; 95% confidence interval, 0.34-0.99). There were no significant associations between nonsteroidal anti-inflammatory drugs and PD. Inverse associations of smoking and caffeine were corroborated using families with PD, thus emphasizing smoking and caffeine as important covariates to consider in genetic studies of PD.

Caffeine dependence in combination with a family history of alcoholism as a predictor of continued use of caffeine during pregnancy.

Science.gov (United States)

Svikis, Dace S; Berger, Nathan; Haug, Nancy A; Griffiths, Roland R

2005-12-01

The purpose of the study was to examine whether caffeine dependence and a family history of alcoholism are associated with continued use of caffeine during pregnancy. Forty-four women seeking obstetrical care in an office-based practice completed questionnaires and provided saliva samples at three prenatal visits occurring 2-3, 3-4, and 7 months postconception. On visit 1, the patients received the physician's instructions to stop using caffeine. Structured interviews were used to assign a diagnosis of caffeine dependence (lifetime) and to identify family history of alcoholism. Outcome measures included self-reported levels of caffeine use and saliva caffeine levels at the three prenatal visits. Although most women eliminated or substantially reduced their caffeine consumption between pregnancy awareness and prenatal visit 1, those with a lifetime diagnosis of caffeine dependence and a family history of alcoholism had higher levels of caffeine use and lower rates of abstinence throughout pregnancy. Saliva caffeine levels confirmed these effects. Withdrawal symptoms, functional impairment, and craving were cited as reasons they failed to eliminate or cut back on caffeine use. Fifty percent of the women with both a lifetime diagnosis of caffeine dependence and a family history of alcoholism continued to use caffeine in amounts (>300 mg/day) greater than those considered safe during pregnancy, compared to none of the women without caffeine dependence and a family history of alcoholism. Women with a lifetime diagnosis of caffeine dependence and a family history of alcoholism also reported higher rates of past cigarette smoking and problematic alcohol use. Caffeine-dependent women with a family history of alcoholism were not able to follow their physician's advice to reduce or eliminate caffeine consumption during pregnancy, despite their wanting to do so. This subgroup may require more intensive intervention to ensure caffeine abstinence and may be at greater risk for

[Caffeine as a preventive drug for Parkinson's disease: epidemiologic evidence and experimental support].

Science.gov (United States)

Góngora-Alfaro, José Luis

Prospective epidemiologic studies performed in large cohorts of men (total: 374,003 subjects) agree in which the risk of suffering Parkinson's disease diminishes progressively as the consumption of coffee and other caffeinated beverages increases. In the case of women (total: 345,184 subjects) the protective effect of caffeine is only observed in menopausal women which do not receive estrogen replacement therapy. Studies with models of acute parkinsonism in rodents have shown that caffeine reduces the loss of nigrostriatal dopaminergic neurons induced with the neurotoxins 6-hidroxidopamine and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, effect that seems to be mediated through blockade of A(2A) adenosine receptors. Recently, it was shown that male rats treated with moderate doses of caffeine (5 mg/kg/day) during six months, followed by a withdrawal period of at least two weeks, developed a greater resistance to the catalepsy induced with the dopaminergic antagonist haloperidol, which was possibly mediated by an increase of dopaminergic transmission in the corpus striatum. More studies are needed to demonstrate unequivocally that caffeine prevents the degeneration of dopaminergic neurons in animal models of moderate, chronic, and progressive parkinsonism, since it could lead to the discovery of more effective drugs for the prevention of aging-related degenerative diseases of the central nervous system.

21 CFR 182.1180 - Caffeine.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Caffeine. 182.1180 Section 182.1180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN....1180 Caffeine. (a) Product. Caffeine. (b) Tolerance. 0.02 percent. (c) Limitations, restrictions, or...

Does Caffeine Enhance Athletic Performance?

Directory of Open Access Journals (Sweden)

Marcou Juliana

2016-04-01

Conclusion: Caffeine consumption may enhance athletic endurance, based on strong evidence, but further research needs to be conducted. High caffeine doses than the optimal, 3-6 mg/kg, before exercise does not confer any additional improvement in athletic performance. Additional, higher caffeine doses may cause side effects in athletes.

Intake at a single, palatable buffet test meal is associated with total body fat and regional fat distribution in children.

Science.gov (United States)

Fearnbach, S Nicole; Thivel, David; Meyermann, Karol; Keller, Kathleen L

2015-09-01

Previous studies testing the relationship between short-term, ad libitum test-meal intake and body composition in children have shown inconsistent relationships. The objective of this study was to determine whether children's intake at a palatable, buffet meal was associated with body composition, assessed by dual-energy X-ray absorptiometry (DXA). A sample of 71 children (4-6 years) participated in 4 sessions where ad libitum food intake was measured. Children's intake at two of the test-meals was retained for the present analysis: a baseline meal consisting of moderately palatable foods and a highly palatable buffet including sweets, sweet-fats, and savory-fats. On the last visit, anthropometrics and DXA were assessed to determine child body composition. Children consumed significantly more calories at the palatable buffet compared to the baseline test-meal. Children's total fat-free mass was positively associated with intake at both the baseline meal and the palatable buffet meal. Total energy intake at both meals and intake of savory-fats at the palatable buffet were positively associated with children's total fat mass, total percent body fat, and percent android fat. Intake of sweet-fats was associated with child fat-free mass index. Intake of sweets was not correlated with body composition. Children's intake at a palatable test-meal, particularly of savory-fat foods, was associated with measures of total and regional body fat. Copyright © 2015 Elsevier Ltd. All rights reserved.

Determination of urine caffeine and its metabolites by use of high-performance liquid chromatography-tandem mass spectrometry: estimating dietary caffeine exposure and metabolic phenotyping in population studies.

Science.gov (United States)

Rybak, Michael E; Pao, Ching-I; Pfeiffer, Christine M

2014-01-01

We have developed and validated a high-performance liquid chromatography-tandem mass spectrometric (LC-MS/MS) method for determining urine caffeine and 14 caffeine metabolites suitable for estimating caffeine exposure and metabolic phenotyping in population studies. Sample preparation consisted solely of a series of simple reagent treatments at room temperature. Stable isotope-labeled analogs were used as internal standards for all analytes. We developed rapid LC-MS/MS separations for both positive and negative ion mode electrospray ionizations to maximize measurement sensitivity. Limits of detection were 0.05-0.1 μmol/L depending on the analytes. Method imprecision, based on total coefficients of variation, was generally 1 μmol/L. Analyte recoveries were typically within 10 % of being quantitative (100 %), and good agreement was observed among analytes measured across different MS/MS transitions. We applied this method to the analysis of a convenience set of human urine samples (n = 115) and were able to detect a majority of the analytes in ≥99 % of samples as well as calculate caffeine metabolite phenotyping ratios for cytochrome P450 1A2 and N-acetyltransferase 2. Whereas existing LC-MS/MS methods are limited in number of caffeine metabolites for which they are validated, or are designed for studies in which purposely elevated caffeine levels are expected, our method is the first of its kind designed specifically for the rapid, sensitive, accurate, and precise measurement of urine caffeine and caffeine metabolites at concentrations relevant to population studies.

Peripubertal Caffeine Exposure Impairs Longitudinal Bone Growth in Immature Male Rats in a Dose- and Time-Dependent Manner.

Science.gov (United States)

Choi, Yun-Young; Choi, Yuri; Kim, Jisook; Choi, Hyeonhae; Shin, Jiwon; Roh, Jaesook

2016-01-01

This study investigated the dose- and time-dependent effects of caffeine consumption throughout puberty in peripubertal rats. A total of 85 male SD rats were randomly divided into four groups: control and caffeine-fed groups with 20, 60, or 120 mg/kg/day through oral gavage for 10, 20, 30, or 40 days. Caffeine decreased body weight gain and food consumption in a dose- and time-dependent manner, accompanied by a reduction in muscle and body fat. In addition, it caused a shortening and lightening of leg bones and spinal column. The total height of the growth plate decreased sharply at 40 days in the controls, but not in the caffeine-fed groups, and the height of hypertrophic zone in the caffeine-fed groups was lower than in the control. Caffeine increased the height of the secondary spongiosa, whereas parameters related to bone formation, such as bone area ratio, thickness and number of trabeculae, and bone perimeter, were significantly reduced. Furthermore, serum levels of IGF-1, estradiol, and testosterone were also reduced by the dose of caffeine exposure. Our results demonstrate that caffeine consumption can dose- and time-dependently inhibit longitudinal bone growth in immature male rats, possibly by blocking the physiologic changes in body composition and hormones relevant to bone growth.

Caffeine Toxicity Due to Supplement Use in Caffeine--Naïve Individual: A Cautionary Tale.

Science.gov (United States)

Lystrup, Robert M; Leggit, Jeffery C

2015-08-01

Thousands of military members self-medicate with dietary supplements containing unknown quantities of pharmacologically active compounds. These poorly regulated substances can cause real harm to the military population, especially when they contain stimulants such as caffeine. When taken regularly, caffeine has several performance-enhancing benefits. However, when used excessively or in vulnerable populations, caffeine can cause several unwanted side effects such as nervousness, sensory disturbances, insomnia, arrhythmia, excitability, inattentiveness, restlessness, mood changes, gastrointestinal disturbances, and even psychosis. Vulnerable patients include the caffeine-naïve, physiologically stressed, young, and mentally ill patients. One such case describes a caffeine-naïve service member who suffered an adverse reaction after taking an allegedly moderate dose of caffeine from a pill he obtained from a teammate. This case highlights the importance of supplement awareness among service members, increased provider vigilance, third party verification, and enhanced regulation on the approval and marketing of dietary supplements. Reprint & Copyright © 2015 Association of Military Surgeons of the U.S.

Adsorption behavior of caffeine as a green corrosion inhibitor for copper

Energy Technology Data Exchange (ETDEWEB)

Souza, Fernando Silvio de [Grupo de Estudos de Processos Eletroquimicos e Eletroanaliticos, Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil); Giacomelli, Cristiano [Departamento de Quimica, Universidade Federal de Santa Maria, Av. Roraima 1000, 97119-900, Santa Maria, RS (Brazil); Goncalves, Reinaldo Simoes [Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, 91501-970, Porto Alegre, RS (Brazil); Spinelli, Almir, E-mail: almir.spinelli@ufsc.br [Grupo de Estudos de Processos Eletroquimicos e Eletroanaliticos, Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil)

2012-12-01

Electrochemical and impedance experiments were carried out to evaluate the corrosion behavior of copper in aerated 0.1 mol L{sup -1} H{sub 2}SO{sub 4} solutions in the presence of three xanthine derivatives with similar chemical structures. The corrosion rate of copper was found to increase in the presence of theophylline and theobromine and decrease in the presence of caffeine. The adsorption and inhibitory effect of caffeine on copper surfaces in aerated 0.1 mol L{sup -1} H{sub 2}SO{sub 4} solutions were then investigated in detail by potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), contact angle measurements, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and fluorescence experiments. The data obtained indicate that caffeine behaves as a cathodic-type inhibitor adsorbing onto the copper surface according to the Temkin isotherm, with the negative Increment G Degree-Sign {sub ads} value of - 31.1 kJ mol{sup -1} signifying a spontaneous adsorption process. The corrosion inhibition efficiency increased with caffeine concentration in the range of 1.0-10.0 mmol L{sup -1}. Furthermore, the EIS results obtained at the open-circuit potential and surface analysis (SEM, EDS and fluorescence) clearly demonstrated the adsorption of the organic compound onto the copper electrode. The contact angle measurements revealed the formation of a hydrophobic protective film. This film covers up to 72% of the total active surface, acts as a protective barrier and prevents interaction between the metal, water and oxygen molecules. - Highlights: Black-Right-Pointing-Pointer We have investigated the adsorption and corrosion inhibition of caffeine on copper surfaces. Black-Right-Pointing-Pointer Caffeine behaves as a cathodic-type inhibitor. Black-Right-Pointing-Pointer Caffeine adsorbs onto copper surface according to Temkin isotherm. Black-Right-Pointing-Pointer There exists the formation of a hydrophobic film that acts as a

Does Caffeine Consumption Modify Cerebrospinal Fluid Amyloid-β Levels in Patients with Alzheimer's Disease?

DEFF Research Database (Denmark)

Travassos, Maria; Santana, Isabel; Baldeiras, Inês

2015-01-01

Caffeine may be protective against Alzheimer's disease (AD) by modulating amyloid-β (Aβ) metabolic pathways. The present work aimed to study a possible association of caffeine consumption with the cerebrospinal fluid (CSF) biomarkers, particularly Aβ. The study included 88 patients with AD or mild...... cognitive impairment. The consumption of caffeine and theobromine was evaluated using a validated food questionnaire. Quantification of caffeine and main active metabolites was performed with liquid chromatography coupled to tandem mass spectrometry. The levels of A(1-42), total tau, and phosphorylated tau...... in the CSF were determined using sandwich ELISA methods and other Aβ species, Aβ(X-38), Aβ(X-40), and Aβ(X-42), with the MSD Aβ Triplex assay. The concentration of caffeine was 0.79±1.15 μg/mL in the CSF and 1.20±1.88 μg/mL in the plasma. No correlation was found between caffeine consumption and Aβ42...

Smoking and caffeine consumption: a genetic analysis of their association.

Science.gov (United States)

Treur, Jorien L; Taylor, Amy E; Ware, Jennifer J; Nivard, Michel G; Neale, Michael C; McMahon, George; Hottenga, Jouke-Jan; Baselmans, Bart M L; Boomsma, Dorret I; Munafò, Marcus R; Vink, Jacqueline M

2017-07-01

Smoking and caffeine consumption show a strong positive correlation, but the mechanism underlying this association is unclear. Explanations include shared genetic/environmental factors or causal effects. This study employed three methods to investigate the association between smoking and caffeine. First, bivariate genetic models were applied to data of 10 368 twins from the Netherlands Twin Register in order to estimate genetic and environmental correlations between smoking and caffeine use. Second, from the summary statistics of meta-analyses of genome-wide association studies on smoking and caffeine, the genetic correlation was calculated by LD-score regression. Third, causal effects were tested using Mendelian randomization analysis in 6605 Netherlands Twin Register participants and 5714 women from the Avon Longitudinal Study of Parents and Children. Through twin modelling, a genetic correlation of r0.47 and an environmental correlation of r0.30 were estimated between current smoking (yes/no) and coffee use (high/low). Between current smoking and total caffeine use, this was r0.44 and r0.00, respectively. LD-score regression also indicated sizeable genetic correlations between smoking and coffee use (r0.44 between smoking heaviness and cups of coffee per day, r0.28 between smoking initiation and coffee use and r0.25 between smoking persistence and coffee use). Consistent with the relatively high genetic correlations and lower environmental correlations, Mendelian randomization provided no evidence for causal effects of smoking on caffeine or vice versa. Genetic factors thus explain most of the association between smoking and caffeine consumption. These findings suggest that quitting smoking may be more difficult for heavy caffeine consumers, given their genetic susceptibility. © 2016 The Authors.Addiction Biology published by John Wiley & Sons Ltd on behalf of Society for the Study of Addiction.

Caffeine metabolites not caffeine protect against riboflavin photosensitized oxidative damage related to skin and eye health

DEFF Research Database (Denmark)

Scurachio, R. S.; Mattiucci, F.; Santos, W. G.

2016-01-01

. Caffeine metabolites rather than caffeine seem accordingly important for the observed protective effect against cutaneous melanoma identified for drinkers of regular but not of decaffeinated coffee. The caffeine metabolites, but not caffeine, were by time resolved single photon counting found to quench...... singlet excited riboflavin through exothermic formation of ground-state precursor complexes indicating importance of hydrogen bounding through keto-enol tautomer's for protection of oxidizable substrates and sensitive structures against riboflavin photosensitization....

Characterization of individuals seeking treatment for caffeine dependence.

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Juliano, Laura M; Evatt, Daniel P; Richards, Brian D; Griffiths, Roland R

2012-12-01

Previous investigations have identified individuals who meet criteria for Diagnostic and Statistical Manual of Mental Disorders (4th ed., text rev.; DSM-IV-TR; American Psychiatric Association, 2000) substance dependence as applied to caffeine, but there is little research on treatments for caffeine dependence. This study aimed to thoroughly characterize individuals who are seeking treatment for problematic caffeine use. Ninety-four individuals who identified as being psychologically or physically dependent on caffeine, or who had tried unsuccessfully to modify caffeine consumption participated in a face-to-face diagnostic clinical interview. They also completed measures concerning caffeine use and quitting history, reasons for seeking treatment, and standardized self-report measures of psychological functioning. Caffeine treatment seekers (mean age 41 years, 55% women) consumed an average of 548 mg caffeine per day. The primary source of caffeine was coffee for 50% of the sample and soft drinks for 37%. Eighty-eight percent reported prior serious attempts to modify caffeine use (mean 2.7 prior attempts), and 43% reported being advised by a medical professional to reduce or eliminate caffeine. Ninety-three percent met criteria for caffeine dependence when generic DSM-IV-TR substance dependence criteria were applied to caffeine use. The most commonly endorsed criteria were withdrawal (96%), persistent desire or unsuccessful efforts to control use (89%), and use despite knowledge of physical or psychological problems caused by caffeine (87%). The most common reasons for wanting to modify caffeine use were health-related (59%) and not wanting to be dependent on caffeine (35%). This investigation reveals that there are individuals with problematic caffeine use who are seeking treatment and suggests that there is a need for effective caffeine dependence treatments. 2013 APA, all rights reserved

The trends in total energy, macronutrients and sodium intake among Japanese: findings from the 1995-2016 National Health and Nutrition Survey.

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Saito, Aki; Imai, Shino; Htun, Nay Chi; Okada, Emiko; Yoshita, Katsushi; Yoshiike, Nobuo; Takimoto, Hidemi

2018-06-04

Monitoring nutritional status of the population is essential in the development and evaluation of national or local health policies. In this study, we aimed to demonstrate analysis on the trends in dietary intake of energy and macronutrients, as well as Na, in Japanese population using the data of series of cross-sectional national surveys - the National Nutrition Survey (NNS) and the National Health Nutrition Survey (NHNS) - during the period from 1995 to 2016. The NNS and NHNS participants aged 20-79 years were included in the analysis. Dietary intake was estimated using 1-d household-based dietary record. The trend in total energy intake, energy intake from macronutrients (fat and protein), Na intake and energy-adjusted Na intake were analysed using regression models adjusted to 2010 age distribution and anthropometry status. A total of 94 270 men and 107 890 women were included the analysis. Total energy intake showed a decreasing trend in both men and women. Similarly, energy intake from protein decreased, but energy intake (%) from fat increased in both sexes. Energy-adjusted Na intake showed a decreasing trend in both men and women. This study identified the decrease in total energy intake and energy intake from protein, whereas there were inverse trends in energy intake from fat among Japanese adults. Continued monitoring of trends in dietary intake will be needed, and there should be efforts to increase the accuracy of current survey procedures.

Caffeine degradation in water by gamma irradiation, ozonation and ozonation/gamma irradiation

Directory of Open Access Journals (Sweden)

Torun Murat

2014-03-01

Full Text Available Aqueous solutions of caffeine were treated with ozone and gamma irradiation. The amounts of remaining caffeine were determined after solid phase extraction as a function of absorbed dose and ozonation time. In addition to this, some important parameters such as inorganic ions, chemical oxygen demand (COD dissolved oxygen and total acidity changes were followed. Caffeine (50 ppm is found to be completely decomposed at 3.0 kGy and 1.2 kGy doses in the absence of H2O2 and in 1.20 mM H2O2 solutions, respectively. In the case of gamma irradiation after ozonation, 50 ppm caffeine was removed at 0.2 kGy when the solution was ozonized for 100 s at a rate of 10 g O3 h-1 in 400 mL 50 ppm paracetamol solution.

Differential Behavioral and Biochemical Responses to Caffeine in Male and Female Rats from a Validated Model of Attention Deficit and Hyperactivity Disorder.

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Nunes, Fernanda; Pochmann, Daniela; Almeida, Amanda Staldoni; Marques, Daniela Melo; Porciúncula, Lisiane de Oliveira

2018-03-20

Epidemiological studies suggest sex differences in attention deficit and hyperactivity disorder (ADHD) symptomatology. The potential benefits of caffeine have been reported in the management of ADHD, but its effects were not properly addressed with respect to sex differences. The present study examined the effects of caffeine (0.3 g/L) administered since childhood in the behavior and brain-derived neurotrophic factor (BDNF) and its related proteins in both sexes of a rat model of ADHD (spontaneously hypertensive rats-SHR). Hyperlocomotion, recognition, and spatial memory disturbances were observed in adolescent SHR rats from both sexes. However, females showed lack of habituation and worsened spatial memory. Although caffeine was effective against recognition memory impairment in both sexes, spatial memory was recovered only in female SHR rats. Besides, female SHR rats showed exacerbated hyperlocomotion after caffeine treatment. SHR rats from both sexes presented increases in the BDNF, truncated and phospho-TrkB receptors and also phospho-CREB levels in the hippocampus. Caffeine normalized BDNF in males and truncated TrkB receptor at both sexes. These findings provide insight into the potential of caffeine against fully cognitive impairment displayed by females in the ADHD model. Besides, our data revealed that caffeine intake since childhood attenuated behavioral alterations in the ADHD model associated with changes in BDNF and TrkB receptors in the hippocampus.

Caffeine reversal of ethanol effects on the multiple sleep latency test, memory, and psychomotor performance.

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Drake, Christopher L; Roehrs, Timothy; Turner, Lauren; Scofield, Holly M; Roth, Thomas

2003-02-01

Caffeine has been shown to reverse some of the performance-impairing effects of ethanol. However, it is not known whether this antagonistic effect of caffeine is mediated by a reduction in sleepiness. The present study assessed physiological alertness/sleepiness, memory, and psychomotor performance following the administration of placebo, ethanol, and caffeine+ethanol combinations. A total of 13 healthy individuals (21-35 years old) underwent four conditions presented in a Latin Square Design: placebo-placebo, ethanol (0.5 g/kg)-placebo, ethanol (0.5 g/kg)-caffeine 150 mg, and ethanol (0.5 g/kg)-caffeine 300-mg. The Multiple Sleep Latency Test (MSLT), psychomotor performance battery, memory test, and mood/sleepiness questionnaires were administered following each condition. The peak breadth ethanol concentration (BrEC) was 0.043+/-0.0197% and did not differ among the three caffeine treatments. As expected, ethanol reduced mean latency on the MSLT. The lowest caffeine dose reversed this effect and the highest dose increased mean latency (greater alertness) significantly beyond placebo levels. Ethanol also impaired psychomotor performance and memory. The 300-mg caffeine dose restored performance and memory measures to placebo levels. Although visual analog ratings of dizziness were increased by ethanol, they were not diminished by either caffeine dose. In conclusion, Low-dose caffeine prevented the sleepiness and performance impairment associated with a moderate dose of ethanol. Thus, caffeine, similar to other stimulants, can reverse the physiologically sedating effects of ethanol, although other negative effects remain.

Total volume and composition of fluid intake and mortality in older women: a cohort study

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Lim, Wai H; Wong, Germaine; Lewis, Joshua R; Lok, Charmaine E; Polkinghorne, Kevan R; Hodgson, Jonathan; Lim, Ee M; Prince, Richard L

2017-01-01

Objectives The health benefits of ‘drinking at least 8 glasses of water a day” in healthy individuals are largely unproven. We aimed to examine the relationship between total fluid and the sources of fluid consumption, risk of rapid renal decline, cardiovascular disease (CVD) mortality and all-cause mortality in elderly women. Design, setting and participants We conducted a longitudinal analysis of a population-based cohort study of 1055 women aged ≥70 years residing in Australia. Main outcome measures The associations between total daily fluid intake (defined as total volume of beverage excluding alcohol and milk) and the types of fluid (water, black tea, coffee, milk and other fluids) measured as cups per day and rapid renal decline, CVD and all-cause mortality were assessed using adjusted logistic and Cox regression analyses. Results Over a follow-up period of 10 years, 70 (6.6%) experienced rapid renal decline and 362 (34.4%) died, of which 142 (13.5%) deaths were attributed to CVD. The median (IQR) intake of total fluid was 10.4 (8.5–12.5) cups per day, with water (median (IQR) 4 (2–6) cups per day) and black tea (median (IQR) 3 (1–4) cups per day) being the most frequent type of fluid consumed. Every cup per day higher intake of black tea was associated with adjusted HRs of 0.90 (95% CI 0.81 to 0.99) and 0.92 (95% CI 0.86 to 0.98) for CVD mortality and all-cause mortality, respectively. There were no associations between black tea intake and rapid renal decline, or between the quantity or type of other fluids, including water intake, and any clinical outcomes. Conclusions Habitual higher intake of black tea may potentially improve long-term health outcomes, independent of treating traditional CVD risk factors, but validation of our study findings is essential. PMID:28341683

Caffeine Consumption Among Naval Aviation Candidates.

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Sather, Thomas E; Williams, Ronald D; Delorey, Donald R; Woolsey, Conrad L

2017-04-01

Education frequently dictates students need to study for prolonged periods of time to adequately prepare for examinations. This is especially true with aviation preflight indoctrination (API) candidates who have to assimilate large volumes of information in a limited amount of time during API training. The purpose of this study was to assess caffeine consumption patterns (frequency, type, and volume) among naval aviation candidates attending API to determine the most frequently consumed caffeinated beverage and to examine if the consumption of a nonenergy drink caffeinated beverage was related to energy drink consumption. Data were collected by means of an anonymous 44-item survey administered and completed by 302 students enrolled in API at Naval Air Station Pensacola, FL. Results indicated the most frequently consumed caffeinated beverage consumed by API students was coffee (86.4%), with daily coffee consumption being approximately 28% and the most frequent pattern of consumption being 2 cups per day (85%). The least frequently consumed caffeinated beverages reported were energy drinks (52%) and energy shots (29.1%). The present study also found that the consumption patterns (weekly and daily) of caffeinated beverages (coffee and cola) were positively correlated to energy drink consumption patterns. Naval aviation candidates' consumption of caffeinated beverages is comparable to other college and high school cohorts. This study found that coffee and colas were the beverages of choice, with energy drinks and energy shots being the least frequently reported caffeinated beverages used. Additionally, a relationship between the consumption of caffeinated beverages and energy drinks was identified.Sather TE, Williams RD, Delorey DR, Woolsey CL. Caffeine consumption among naval aviation candidates. Aerosp Med Hum Perform. 2017; 88(4):399-405.