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Lowery LM, Anderson DE, Scanlon KF, Stack A, Escalante G, Campbell SC, Kerksick CM, Nelson MT, Ziegenfuss TN, VanDusseldorp TA, Kalman DS, Campbell BI, Kreider RB, Antonio J. International society of sports nutrition position stand: coffee and sports performance. J Int Soc Sports Nutr 2023; 20:2237952. [PMID: 37498180 PMCID: PMC10375938 DOI: 10.1080/15502783.2023.2237952] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Accepted: 07/11/2023] [Indexed: 07/28/2023] Open
Abstract
Based on review and critical analysis of the literature regarding the contents and physiological effects of coffee related to physical and cognitive performance conducted by experts in the field and selected members of the International Society of Sports Nutrition (ISSN), the following conclusions represent the official Position of the Society:(1) Coffee is a complex matrix of hundreds of compounds. These are consumed with broad variability based upon serving size, bean type (e.g. common Arabica vs. Robusta), and brew method (water temperature, roasting method, grind size, time, and equipment).(2) Coffee's constituents, including but not limited to caffeine, have neuromuscular, antioxidant, endocrine, cognitive, and metabolic (e.g. glucose disposal and vasodilation) effects that impact exercise performance and recovery.(3) Coffee's physiologic effects are influenced by dose, timing, habituation to a small degree (to coffee or caffeine), nutrigenetics, and potentially by gut microbiota differences, sex, and training status.(4) Coffee and/or its components improve performance across a temporal range of activities from reaction time, through brief power exercises, and into the aerobic time frame in most but not all studies. These broad and varied effects have been demonstrated in men (mostly) and in women, with effects that can differ from caffeine ingestion, per se. More research is needed.(5) Optimal dosing and timing are approximately two to four cups (approximately 473-946 ml or 16-32 oz.) of typical hot-brewed or reconstituted instant coffee (depending on individual sensitivity and body size), providing a caffeine equivalent of 3-6 mg/kg (among other components such as chlorogenic acids at approximately 100-400 mg per cup) 60 min prior to exercise.(6) Coffee has a history of controversy regarding side effects but is generally considered safe and beneficial for healthy, exercising individuals in the dose range above.(7) Coffee can serve as a vehicle for other dietary supplements, and it can interact with nutrients in other foods.(8) A dearth of literature exists examining coffee-specific ergogenic and recovery effects, as well as variability in the operational definition of "coffee," making conclusions more challenging than when examining caffeine in its many other forms of delivery (capsules, energy drinks, "pre-workout" powders, gum, etc.).
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Affiliation(s)
- Lonnie M Lowery
- Walsh University, Department of Exercise Science, North Canton, OH, USA
- Nutrition, Exercise and Wellness Associates, Cuyahoga Falls, USA
| | - Dawn E Anderson
- Indiana Institute of Technology, Department of Biological and Physical Sciences, Fort Wayne, USA
| | - Kelsey F Scanlon
- Walsh University, Department of Exercise Science, North Canton, OH, USA
| | - Abigail Stack
- University of Mount Union, Department of Exercise, Nutrition, and Sport Science Alliance, USA
| | | | - Sara C Campbell
- The State University of New Jersey, Department of Kinesiology and Health, Rutgers, New Brunswick, USA
| | - Chad M Kerksick
- Lindenwood University, Exercise and Performance Nutrition Laboratory, St. Charles, USA
| | | | | | - Trisha A VanDusseldorp
- Bonafide Health, LLC p/b JDS Therapeutics, Harrison, USA
- Jacksonville University, Department of Health and Exercise Sciences, Jacksonville, USA
| | - Douglas S Kalman
- Nova Southeastern University, Department of Nutrition, College of Osteopathic Medicine, Fort Lauderdale, USA
| | - Bill I Campbell
- University of South Florida, Performance & Physique Enhancement Laboratory, Tampa, USA
| | - Richard B Kreider
- Texas A&M University, Exercise & Sport Nutrition Lab, Department of Kinesiology and Sports Management, College Station, USA
| | - Jose Antonio
- Nova Southeastern University, Department of Health and Human Performance, Davie, USA
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Babić Leko M, Gunjača I, Pleić N, Zemunik T. Environmental Factors Affecting Thyroid-Stimulating Hormone and Thyroid Hormone Levels. Int J Mol Sci 2021; 22:6521. [PMID: 34204586 PMCID: PMC8234807 DOI: 10.3390/ijms22126521] [Citation(s) in RCA: 59] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 06/11/2021] [Accepted: 06/14/2021] [Indexed: 01/09/2023] Open
Abstract
Thyroid hormones are necessary for the normal functioning of physiological systems. Therefore, knowledge of any factor (whether genetic, environmental or intrinsic) that alters the levels of thyroid-stimulating hormone (TSH) and thyroid hormones is crucial. Genetic factors contribute up to 65% of interindividual variations in TSH and thyroid hormone levels, but many environmental factors can also affect thyroid function. This review discusses studies that have analyzed the impact of environmental factors on TSH and thyroid hormone levels in healthy adults. We included lifestyle factors (smoking, alcohol consumption, diet and exercise) and pollutants (chemicals and heavy metals). Many inconsistencies in the results have been observed between studies, making it difficult to draw a general conclusion about how a particular environmental factor influences TSH and thyroid hormone levels. However, lifestyle factors that showed the clearest association with TSH and thyroid hormones were smoking, body mass index (BMI) and iodine (micronutrient taken from the diet). Smoking mainly led to a decrease in TSH levels and an increase in triiodothyronine (T3) and thyroxine (T4) levels, while BMI levels were positively correlated with TSH and free T3 levels. Excess iodine led to an increase in TSH levels and a decrease in thyroid hormone levels. Among the pollutants analyzed, most studies observed a decrease in thyroid hormone levels after exposure to perchlorate. Future studies should continue to analyze the impact of environmental factors on thyroid function as they could contribute to understanding the complex background of gene-environment interactions underlying the pathology of thyroid diseases.
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Affiliation(s)
| | | | | | - Tatijana Zemunik
- Department of Medical Biology, School of Medicine, University of Split, Šoltanska 2, 21000 Split, Croatia; (M.B.L.); (I.G.); (N.P.)
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Oliveira KJ, Chiamolera MI, Giannocco G, Pazos-Moura CC, Ortiga-Carvalho TM. Thyroid Function Disruptors: from nature to chemicals. J Mol Endocrinol 2018; 62:JME-18-0081. [PMID: 30006341 DOI: 10.1530/jme-18-0081] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 07/03/2018] [Accepted: 07/12/2018] [Indexed: 12/11/2022]
Abstract
The modern concept of thyroid disruptors includes man-made chemicals and bioactive compounds from food that interfere with any aspect of the hypothalamus-pituitary-thyroid axis, thyroid hormone biosynthesis and secretion, blood and transmembrane transport, metabolism and local action of thyroid hormones. This review highlights relevant disruptors that effect populations through their diet: directly from food itself (fish oil and polyunsaturated fatty acids, pepper, coffee, cinnamon and resveratrol/grapes), through vegetable cultivation (pesticides) and from containers for food storage and cooking (bisphenol A, phthalates and polybrominated diphenyl ethers). Due to the vital role of thyroid hormones during every stage of life, we review effects from the gestational period through to adulthood, including evidence from in vitro studies, rodent models, human trials and epidemiological studies.
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Affiliation(s)
- Karen J Oliveira
- K Oliveira, Laboratório de Fisiologia Endócrina e Metabologia, Physiology and Pharmacology, Federal Fluminense University, Niteroi, Brazil
| | - Maria Izabel Chiamolera
- M Chiamolera, Endocrinology, Universidade Federal de Sao Paulo Escola Paulista de Medicina, Sao Paulo, Brazil
| | - Gisele Giannocco
- G Giannocco, Laboratório de Endocrinologia Molecular e Translacional, Universidade Federal de Sao Paulo Escola Paulista de Medicina, Sao Paulo, Brazil
| | - Carmen Cabanelas Pazos-Moura
- C Pazos-Moura, Laboratório de Endocrinologia Molecular, Instituto de Biofisica Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Tania Maria Ortiga-Carvalho
- T Ortiga-Carvalho, Laboratório de Endocrinologia Translacional, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
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Papakonstantinou E, Kechribari I, Sotirakoglou Κ, Tarantilis P, Gourdomichali T, Michas G, Kravvariti V, Voumvourakis K, Zampelas A. Acute effects of coffee consumption on self-reported gastrointestinal symptoms, blood pressure and stress indices in healthy individuals. Nutr J 2016; 15:26. [PMID: 26979712 PMCID: PMC4791892 DOI: 10.1186/s12937-016-0146-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 03/10/2016] [Indexed: 12/22/2022] Open
Abstract
Background It has been suggested that coffee may affect the gut-brain axis with conflicting outcomes. Moreover, there is insufficient evidence to determine whether the type or temperature of coffee consumed will have a different impact on the gut-brain axis. The purpose of this study was to investigate the effects of acute coffee consumption on the following: 1. self-reported GI symptoms and salivary gastrin, 2. stress indices [salivary cortisol and alpha-amylase (sAA)] and psychometric measures, and 3. blood pressure (BP), in healthy, daily coffee consuming individuals in non-stressful conditions. Methods This was a randomized, double blind, crossover clinical trial, in which 40 healthy individuals (20 men, 20 women), 20–55 years of age, randomly consumed four 200 ml coffee beverages containing 160 mg caffeine (hot and cold instant coffee, cold espresso, hot filtered coffee), 1 week apart. Salivary samples and psychometric questionnaires were collected at baseline and post-coffee consumption at 15,30, and 60 min for salivary gastrin and sAA measurements and at 60,120, and 180 min for cortisol measurements. BP was measured at beginning and end of each intervention. ClinicalTrials.gov ID: NCT02253628 Results Coffee consumption significantly increased sAA activity (P = 0.041), with significant differences only between cold instant and filter coffee at 15 and 30 min post-consumption (P < 0.05). Coffee temporarily increased salivary gastrin, without differences between coffee types. Coffee did not affect salivary cortisol or self-reported anxiety levels. Coffee consumption significantly increased BP, within the healthy physiological levels, in a gender specific manner at the end of the experimental periods, without differences between coffee types. Conclusion Acute coffee consumption in non-stressful conditions activated sAA and BP but not salivary cortisol, indicating activation of the sympathetic nervous system. Post-coffee sAA increase without a concomitant cortisol increase may also indicate that coffee may have some anti-stress properties.
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Affiliation(s)
- Emilia Papakonstantinou
- Department of Food Science and Human Nutrition, Agricultural University of Athens, IeraOdos 75, Athens, 11855, Greece.
| | - Ioanna Kechribari
- Department of Food Science and Human Nutrition, Agricultural University of Athens, IeraOdos 75, Athens, 11855, Greece
| | | | - Petros Tarantilis
- Department of Food Science and Human Nutrition, Agricultural University of Athens, IeraOdos 75, Athens, 11855, Greece
| | - Theodora Gourdomichali
- Department of Food Science and Human Nutrition, Agricultural University of Athens, IeraOdos 75, Athens, 11855, Greece
| | - George Michas
- Department of Food Science and Human Nutrition, Agricultural University of Athens, IeraOdos 75, Athens, 11855, Greece
| | - Vassiliki Kravvariti
- Department of Food Science and Human Nutrition, Agricultural University of Athens, IeraOdos 75, Athens, 11855, Greece
| | - Konstantinos Voumvourakis
- Second Department of Neurology, University of Athens Medical School, "Attikon" University Hospital, Athens, Greece
| | - Antonis Zampelas
- Department of Food Science and Human Nutrition, Agricultural University of Athens, IeraOdos 75, Athens, 11855, Greece.,Department of Nutrition and Health, United Arab Emirates University, Al Ain, United Arab Emirates
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Sousa AMAD, Suzuki FA. Effect of caffeine on cervical vestibular-evoked myogenic potential in healthy individuals1. Braz J Otorhinolaryngol 2014; 80:226-30. [PMID: 25153107 PMCID: PMC9535482 DOI: 10.1016/j.bjorl.2014.02.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2013] [Accepted: 02/01/2014] [Indexed: 12/11/2022] Open
Abstract
Introduction Aim Method Result Conclusion
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Affiliation(s)
- Ana Maria Almeida de Sousa
- Instituto de Assistência Médica ao Servidor Público Estadual (IAMSPE), São Paulo, SP, Brazil
- Corresponding author.
| | - Fabio Akira Suzuki
- Instituto de Assistência Médica ao Servidor Público Estadual (IAMSPE), São Paulo, SP, Brazil
- Universidade Federal de São Paulo (UNIFESP/EPM), São Paulo, SP, Brazil
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Garde AH, Persson R, Hansen ÅM, Österberg K, Ørbæk P, Eek F, Karlson B. Effects of lifestyle factors on concentrations of salivary cortisol in healthy individuals. Scandinavian Journal of Clinical and Laboratory Investigation 2009; 69:242-50. [DOI: 10.1080/00365510802483708] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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MacKenzie T, Comi R, Sluss P, Keisari R, Manwar S, Kim J, Larson R, Baron JA. Metabolic and hormonal effects of caffeine: randomized, double-blind, placebo-controlled crossover trial. Metabolism 2007; 56:1694-8. [PMID: 17998023 DOI: 10.1016/j.metabol.2007.07.013] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2007] [Accepted: 07/16/2007] [Indexed: 11/28/2022]
Abstract
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.
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Affiliation(s)
- Todd MacKenzie
- Department of Medicine, Dartmouth Medical School, Hanover, NH 03755, USA.
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8
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Harris A, Ursin H, Murison R, Eriksen HR. Coffee, stress and cortisol in nursing staff. Psychoneuroendocrinology 2007; 32:322-30. [PMID: 17350175 DOI: 10.1016/j.psyneuen.2007.01.003] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2006] [Revised: 01/07/2007] [Accepted: 01/09/2007] [Indexed: 10/23/2022]
Abstract
According to cognitive activation theory, long-lasting work demands without rest or lack of coping may lead to sustained activation and pathology. Cortisol is one of the most important stress hormones in humans and increased basal levels of cortisol are considered a valid marker for sustained activation. In order to investigate this association further, we investigate the relationships between salivary cortisol profiles, job stress, work load (effort/reward, demand/control) and health (subjective health complaints and health-related quality of life) in a population of health care workers. Forty-four women filled in a questionnaire and collected five saliva samples on two consecutive working days (1: wake-up time, 2: wake-up time+30 min, 3: wake-up time+45 min, 4: 1500 h and 5: 2200 h). There was no relationship between psychosocial factors at work and cortisol levels in the morning (cortisol level at wake-up time and awakening cortisol response (ACR)). Only the confounding variable tobacco reached a significant level in the hierarchical regressions analyses. Our significant findings are limited to the afternoon decline and the evening values. The decrease during the day relates to decision authority, physical functioning, general health, and vitality in the single, unadjusted regression analyses. The decrease also relates to coffee intake, which we included originally as a confounding variable. In the final hierarchical regression of the evening values, only decision authority and coffee were significantly related to cortisol levels in the evening.
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Affiliation(s)
- Anette Harris
- Unifob health, Christiesgt 13, N-5015 Bergen, Norway
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9
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Hadjicharalambous M, Georgiades E, Kilduff LP, Turner AP, Tsofliou F, Pitsiladis YP. Influence of caffeine on perception of effort, metabolism and exercise performance following a high-fat meal. J Sports Sci 2006; 24:875-87. [PMID: 16815783 DOI: 10.1080/02640410500249399] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
This study examined the effects of caffeine, co-ingested with a high fat meal, on perceptual and metabolic responses during incremental (Experiment 1) and endurance (Experiment 2) exercise performance. Trained participants performed three constant-load cycling tests at approximately 73% of maximal oxygen uptake (VO2max) for 30 min at 20 degrees C (Experiment 1, n = 8) and to the limit of tolerance at 10 degrees C (Experiment 2, n = 10). The 30 min constant-load exercise in Experiment 1 was followed by incremental exercise (15 W . min-1) to fatigue. Four hours before the first test, the participants consumed a 90% carbohydrate meal (control trial); in the remaining two tests, the participants consumed a 90% fat meal with (fat + caffeine trial) and without (fat-only trial) caffeine. Caffeine and placebo were randomly assigned and ingested 1 h before exercise. In both experiments, ratings of perceived leg exertion were significantly lower during the fat + caffeine than fat-only trial (Experiment 1: P < 0.001; Experiment 2: P < 0.01). Ratings of perceived breathlessness were significantly lower in Experiment 1 (P < 0.01) and heart rate higher in Experiment 2 (P < 0.001) on the fat + caffeine than fat-only trial. In the two experiments, oxygen uptake, ventilation, blood [glucose], [lactate] and plasma [glycerol] were significantly higher on the fat + caffeine than fat-only trial. In Experiment 2, plasma [free fatty acids], blood [pyruvate] and the [lactate]:[pyruvate] ratio were significantly higher on the fat + caffeine than fat-only trial. Time to exhaustion during incremental exercise (Experiment 1: control: 4.9, s = 1.8 min; fat-only: 5.0, s = 2.2 min; fat + caffeine: 5.0, s = 2.2 min; P > 0.05) and constant-load exercise (Experiment 2: control: 116 (88 - 145) min; fat-only: 122 (96 - 144) min; fat + caffeine: 127 (107 - 176) min; P > 0.05) was not different between the fat-only and fat + caffeine trials. In conclusion, while a number of metabolic responses were increased during exercise after caffeine ingestion, perception of effort was reduced and this may be attributed to the direct stimulatory effect of caffeine on the central nervous system. However, this caffeine-induced reduction in effort perception did not improve exercise performance.
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Scarth JP. Modulation of the growth hormone-insulin-like growth factor (GH-IGF) axis by pharmaceutical, nutraceutical and environmental xenobiotics: an emerging role for xenobiotic-metabolizing enzymes and the transcription factors regulating their expression. A review. Xenobiotica 2006; 36:119-218. [PMID: 16702112 DOI: 10.1080/00498250600621627] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The growth hormone-insulin-like growth factor (GH-IGF) axis has gained considerable focus over recent years. One cause of this increased interest is due to a correlation of age-related decline in plasma GH/IGF levels with age-related degenerative processes, and it has led to the prescribing of GH replacement therapy by some practitioners. On the other hand, however, research has also focused on the pro-carcinogenic effects of high GH-IGF levels, providing strong impetus for finding regimes that reduce its activity. Whereas the effects of GH/IGF activity on the action of xenobiotic-metabolizing enzyme systems is reasonably well appreciated, the effects of xenobiotic exposure on the GH-IGF axis has not received substantial review. Relevant xenobiotics are derived from pharmaceutical, nutraceutical and environmental exposure, and many of the mechanisms involved are highly complex in nature, not easily predictable from existing in vitro tests and do not always predict well from in vivo animal models. After a review of the human and animal in vivo and in vitro literature, a framework for considering the different levels of direct and indirect modulation by xenobiotics is developed herein, and areas that still require further investigation are highlighted, i.e. the actions of common endocrine disruptors such as pesticides and phytoestrogens, as well as the role of xenobiotic-metabolizing enzymes and the transcription factors regulating their expression. It is anticipated that a fuller appreciation of the existing human paradigms for GH-IGF axis modulation gained through this review may help explain some of the variation in levels of plasma IGF-1 and its binding proteins in the population, aid in the prescription of particular dietary regimens to certain individuals such as those with particular medical conditions, guide the direction of long-term drug/nutraceutical safety trials, and stimulate ideas for future research. It also serves to warn athletes that using compounds touted as performance enhancing because they promote short-term GH release could in fact be detrimental to performance in the long-run.
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Affiliation(s)
- J P Scarth
- The Horseracing Forensic Laboratories (HFL), Fordham, UK.
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Abstract
The International Olympic Committee, the World Anti-Doping Agency, and International Sport Federations have banned and restricted the use of many stimulants including prescription and over-the-counter medications and dietary supplements. In addition to elite athletes, people of all ages use stimulants in attempts to improve athletic performance, alter body composition, and increase levels of energy. Here we introduce a seven-stage model designed to facilitate informed decision-making by individuals taking or thinking of taking stimulants for sport, health, and/or appearance reasons. We review for amphetamines, over-the counter sympathomimetics, and caffeine their performance-enhancing and performance-degrading effects, health benefits and mechanisms of action, medical side effects, and legal, ethical, safety, and financial implications.
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Affiliation(s)
- Ron Bouchard
- Department of Pharmacology, University of Manitoba, Winnipeg, Manitoba, Canada
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12
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Huang TH, Yang RS, Hsieh SS, Liu SH. Effects of caffeine and exercise on the development of bone: a densitometric and histomorphometric study in young Wistar rats. Bone 2002; 30:293-9. [PMID: 11792600 DOI: 10.1016/s8756-3282(01)00659-7] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
High doses of caffeine will induce calcium loss and influence the normal development of bone, whereas the proper exercise has positive effects on bone metabolism. This study investigated the possible effects of exercise to antagonize the caffeine-induced impairment of bone development in young male Wistar rats. A total of 32 male rats (5 weeks old) were divided randomly into four groups: group 1 rats were fed caffeine; group 2 rats were prescribed an exercise program; group 3 rats were fed caffeine and prescribed an exercise program; and group 4 rats served as the control group. The caffeine was fed via the animals' dietary water and the dosage was 10 mg/100 g body weight per day, 3 days a week. The exercise program was carried out on a treadmill for 10 weeks (5 days/week, 1 h/day, 70% VO(2)max). Body weight was measured weekly. After sacrifice, the tibia length was measured and the tibia was processed for histomorphometric analysis. Bone mineral density was measured by dual-energy X-ray absorptiometer at three different sites of the tibia. In addition, the calcium content of the right femur was measured by atomic absorptiometry. The results showed that both exercise and caffeine significantly lowered the body weight gain. Rats fed with caffeine (groups 1 and 3) had a significantly longer tibia as compared with the non-caffeine-fed rats (groups 2 and 4) (p = 0.0149). The histomorphometry study showed that thickness of the growth plate in the proliferative zone, the hypertrophic zone, and total growth plate was greater in caffeine-fed groups than in non-caffeine-fed groups. The cell number in the proliferative zone was higher in the caffeine-fed groups. Area ratio of trabeculae in the primary spongiosa of rats in groups 1 and 2 were significantly greater than the control group. Caffeine feeding (groups 1 and 3) induced a lower area ratio of bone trabeculae in the secondary spongiosa, whereas exercise training (groups 2 and 3) increased the thickness of the trabeculae. The exercise program counteracted the negative effect of caffeine on the trabecular thickness, but did not correct the trabecular bone ratio. The bone mineral density (BMD) of the tibia was significantly lower in caffeine-fed rats, and the exercise program did not show any counteracting effect on the caffeine-induced BMD reduction. The calcium content assay showed that caffeine feeding decreased the weight and total calcium content of the femur. Again this exercise program did not counterbalance the negative effects of caffeine. In conclusion, high doses of caffeine seemed to stimulate the growth of long bone. However, it caused more serious negative effects on bone, including bone mineral loss, lower BMD, and lower calcium content. Exercise training at 70% VO(2)max had little antagonizing effect on caffeine-induced impairment of bone formation. Therefore, the best way to prevent caffeine-induced negative effects on bone development is to lower caffeine exposure.
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Affiliation(s)
- T H Huang
- Department of Physical Education, National Taiwan Normal University, Taipei, Taiwan
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HASE T, KOMINE Y, MEGURO S, TAKEDA Y, TAKAHASHI H, MATSUI Y, INAOKA S, KATSURAGI Y, TOKIMITSU I, SHIMASAKI H, ITAKURA H. Anti-obesity Effects of Tea Catechins in Humans. J Oleo Sci 2001. [DOI: 10.5650/jos.50.599] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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al'Absi M, Lovallo WR, Pincomb GA, Sung BH, Wilson MF. Adrenocortical effects of caffeine at rest and during mental stress in borderline hypertensive men. Int J Behav Med 1995; 2:263-75. [PMID: 16250778 DOI: 10.1207/s15327558ijbm0203_5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
We examined the effect or dietary doses of caffeine (3.3 mg/kg, equivalent to 2 to 3 cups of coffee) on adrenocortical responses to behavioral stress in borderline hypertensive (BH) men using a randomized, double-blind, caffeine-placebo crossover design. Cortisol levels were assessed in BH men and matched normotensive (NT) controls at rest and in response to 35 min of continuous work on a psychomotor task alternating with mental arithmetic. Caffeine at rest elevated cortisol among BHs hut not among NTs. Both groups showed significant cortisol responses to caffeine combined with the tasks. These findings may have implications for the dietary use of caffeine in persons at risk for hypertension when faced with stressful situations.
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Affiliation(s)
- M al'Absi
- Veterans Affairs Medical Center, Department of Psychiatry and Behavioral Sciences, University of Oklahoma Sciences Center, Oklahoma City 73104, USA
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15
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Landolt HP, Werth E, Borbély AA, Dijk DJ. Caffeine intake (200 mg) in the morning affects human sleep and EEG power spectra at night. Brain Res 1995; 675:67-74. [PMID: 7796154 DOI: 10.1016/0006-8993(95)00040-w] [Citation(s) in RCA: 114] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Adenosine has been implicated in the physiological regulation of sleep propensity. The adenosine-receptor-antagonist, caffeine (100 mg), administered immediately prior to a nocturnal sleep episode, has previously been shown to lower sleep propensity as indexed by a reduced sleep efficiency, a reduced EEG power density in low delta frequencies and enhanced power density in the frequency range of sleep spindles. To further investigate the role of adenosine in sleep regulation we administered 200 mg of caffeine at 07.10 h and analyzed the sleep stages and EEG power spectra during the subsequent night in nine healthy men. Caffeine levels in saliva decreased from a maximum of 17 mumol/l one hour after intake, to 3 mumol/l immediately prior to the sleep episode starting at 23.00 h. Compared to placebo, sleep efficiency and total sleep time were significantly reduced. EEG power density in nonREM sleep was suppressed in the 0.25-0.5 Hz band and enhanced in the frequency range of sleep spindles (11.25-12.0 Hz and 13.25-14.0 Hz). In REM sleep EEG power density was suppressed in the frequency range of 0.75-4.5 and 5.25-6.0 Hz. The data indicate that a saliva level of caffeine as low as 3 mumol/l directly affects sleep propensity or, alternatively, that the presence of caffeine in the central nervous system during the waking episode reduces the progressive increase of sleep propensity associated with wakefulness.
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Affiliation(s)
- H P Landolt
- Institute of Pharmacology, University of Zürich, Switzerland
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Larrick JW. The methyl xanthine hypothesis: does tea consumption by Tibetan natives blunt the effects of high altitude? Med Hypotheses 1991; 34:99-104. [PMID: 2041498 DOI: 10.1016/0306-9877(91)90174-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Kraemer WJ, Rock PB, Fulco CS, Gordon SE, Bonner JP, Cruthirds CD, Marchitelli LJ, Trad L, Cymerman A. Influence of altitude and caffeine during rest and exercise on plasma levels of proenkephalin peptide F. Peptides 1988; 9:1115-9. [PMID: 3244560 DOI: 10.1016/0196-9781(88)90098-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The purpose of this study was to examine the resting and exercise response patterns of plasma Peptide F immunoreactivity (ir) to altitude exposure (4300 m) and caffeine ingestion (4 mg.kg b.w.-1). Nine healthy male subjects performed exercise tests to exhaustion (80-85% VO2max) at sea level (50 m), during an acute altitude exposure (1 hr, hypobaric chamber, 4300 m) and after a chronic (17-day sojourn, 4300 m) altitude exposure. Using a randomized, double-blind/placebo experimental design, a placebo or caffeine drink was ingested 1 hour prior to exercise. Exercise (without caffeine) significantly (p less than 0.05) increased plasma Peptide F ir values during exercise at chronic altitude only. Caffeine ingestion significantly increased plasma Peptide F ir concentrations during exercise and in the postexercise period at sea level. Conversely caffeine ingestion at altitude resulted in significant reductions in the postexercise plasma Peptide F ir values. The results of this study demonstrate that the exercise and recovery response patterns of plasma Peptide F ir may be significantly altered by altitude exposure and caffeine ingestion. These data support further study examining relationships between Peptide F (and other enkephalin-containing polypeptides) and epinephrine release in response to these types of physiological stresses.
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Affiliation(s)
- W J Kraemer
- Exercise Physiology Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA 01760-5007
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Lee MA, Flegel P, Cameron OG, Greden JF. Chronic caffeine consumption and the dexamethasone suppression test in depression. Psychiatry Res 1988; 24:61-5. [PMID: 3393618 DOI: 10.1016/0165-1781(88)90140-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Acute caffeine administration increases cortisol and converts the dexamethasone suppression test (DST) to nonsuppression in normal humans; data concerning chronic administration as well as effects in depressed patients are minimal. To determine whether caffeine intake influenced DST results in depression, we retrospectively studied the relationship between regular daily caffeine consumption and pretreatment DST status in major depressives. Daily intake was not correlated with either post-DST cortisol levels or symptom ratings. These data suggest that chronic caffeine use is unlikely to be a major factor in dysregulation of the hypothalamic-pituitary-adrenal axis in depression, perhaps because of the development of tolerance.
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Affiliation(s)
- M A Lee
- Department of Psychiatry, University of Michigan, Ann Arbor
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Lieberman HR, Wurtman RJ, Emde GG, Roberts C, Coviella IL. The effects of low doses of caffeine on human performance and mood. Psychopharmacology (Berl) 1987; 92:308-12. [PMID: 3114783 DOI: 10.1007/bf00210835] [Citation(s) in RCA: 242] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Caffeine is thought to have stimulant-like behavioral effects on mood and performance. However few behavioral studies have examined this substance's acute effects when administered in a range of doses that include the low doses typically found in foods and over-the-counter drugs. We therefore gave single doses of caffeine (32, 64, 128 and 256 mg) to 20 healthy male subjects and assessed various aspects of performance and self-reported mood states, as well as plasma caffeine concentration. As little as 32 mg (which elevated plasma caffeine concentration to less than 1 microgram/ml), typical of the dose found in a single serving of a cola beverage, and less than that found in a single cup of coffee or a single dose of over-the-counter drugs, significantly improved auditory vigilance and visual reaction time. All other caffeine doses administered also significantly improved performance on these tests. No adverse behavioral effects, such as increased anxiety or impaired motor performance, were noted even at the highest dose administered.
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Bruce M, Scott N, Lader M, Marks V. The psychopharmacological and electrophysiological effects of single doses of caffeine in healthy human subjects. Br J Clin Pharmacol 1986; 22:81-7. [PMID: 3741730 PMCID: PMC1401080 DOI: 10.1111/j.1365-2125.1986.tb02883.x] [Citation(s) in RCA: 90] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The effects of single doses of anhydrous caffeine (250 mg and 500 mg) and placebo on physiological, psychological measures and subjective feelings were studied in a double-blind, cross-over study in nine healthy subjects who had abstained from caffeine-containing beverages for 24 h before each occasion. Caffeine and caffeine metabolites in plasma and urine were assayed. Peak plasma concentrations were observed at 1 to 2 h with an approximate half-life of 5 h. The concentrations of the metabolite 1,7-dimethylxanthine increased during the 5 h. The major urine metabolite was 1-methyluric acid. The EEG showed a dose-related decrease in log 'theta' power and a decrease in log 'alpha' power. Other dose-related effects were an increase in skin conductance level (sweat-gland activity) and self rating of alertness. Ratings of headache and tiredness were decreased by the caffeine. The study illustrates the complexities of studying a drug which is widely taken and which is often associated with withdrawal effects.
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Grome JJ, Stefanovich V. Differential effects of methylxanthines on local cerebral blood flow and glucose utilization in the conscious rat. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 1986; 333:172-7. [PMID: 3748197 DOI: 10.1007/bf00506522] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The aim of this study was to test the effects of the three "classical" methylxanthines, theophylline, caffeine and theobromine, on local cerebral blood flow and glucose utilization. Equimolar doses (1.6 mumol/kg/min i.v.) of theophylline and caffeine produced increases in local cerebral glucose utilization and decreases in local cerebral blood flow. These compounds, therefore, re-set the ratio of cerebral blood flow per unit of glucose utilization at a lower level. These results are interpreted with respect to the known adenosine antagonist properties of caffeine and theophylline. Theobromine, a substance with less significant adenosine antagonist properties, had minimal effects on local cerebral blood flow and glucose utilization at a dose of 1.6 mumol/kg/min i.v. These data may provide supportive evidence for the hypothesis that adenosine plays an important role in cerebral blood flow-metabolism coupling.
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