Caffeine is a proven ergogenic aid in humans. [58] Caffeine improves athletic performance in aerobic (especially endurance sports) and anaerobic conditions. [58] Moderate doses of caffeine (around 5mg/kg [58]) can improve sprint performance, [59] cycling and running time trial performance, [58] endurance (i.e., it delays the onset of muscle fatigue and central fatigue), [58] [60] [61] and cycling power output. [58] Caffeine increases basal metabolic rate in adults. [62] [63] [64] Caffeine ingestion prior to aerobic exercise increases fat oxidation, particularly in persons with low physical fitness. [65] Chen LW, Wu Y, Neelakantan N, Chong MF, Pan A, van Dam RM (May 2016). "Maternal caffeine intake during pregnancy and risk of pregnancy loss: a categorical and dose-response meta-analysis of prospective studies". Public Health Nutrition. 19 (7): 1233–44. doi: 10.1017/S1368980015002463. PMC 10271029. PMID 26329421. Caffeine is a central nervous system stimulant that may reduce fatigue and drowsiness. [12] At normal doses, caffeine has variable effects on learning and memory, but it generally improves reaction time, wakefulness, concentration, and motor coordination. [52] [53] The amount of caffeine needed to produce these effects varies from person to person, depending on body size and degree of tolerance. [52] The desired effects arise approximately one hour after consumption, and the desired effects of a moderate dose usually subside after about three or four hours. [7]

Caffeine - Zhorn Software Caffeine - Zhorn Software

The biosynthesis of caffeine is an example of convergent evolution among different species. [202] [203] [204] a b Qi H, Li S (April 2014). "Dose-response meta-analysis on coffee, tea and caffeine consumption with risk of Parkinson's disease". Geriatrics & Gerontology International. 14 (2): 430–9. doi: 10.1111/ggi.12123. PMID 23879665. S2CID 42527557. Cano-Marquina A, Tarín JJ, Cano A (May 2013). "The impact of coffee on health". Maturitas. 75 (1): 7–21. doi: 10.1016/j.maturitas.2013.02.002. PMID 23465359. A cluster of behavioural, cognitive, and physiological phenomena that develop after repeated substance use and that typically include a strong desire to take the drug, difficulties in controlling its use, persisting in its use despite harmful consequences, a higher priority given to drug use than to other activities and obligations, increased tolerance, and sometimes a physical withdrawal state. Caffeine can delay or prevent sleep and improves task performance during sleep deprivation. [54] Shift workers who use caffeine make fewer mistakes that could result from drowsiness. [55]a b c d van Dam RM, Hu FB, Willett WC (July 2020). "Coffee, Caffeine, and Health". The New England Journal of Medicine. 383 (4): 369–378. doi: 10.1056/NEJMra1816604. PMID 32706535. S2CID 220731550. Death from caffeine ingestion appears to be rare, and most commonly caused by an intentional overdose of medications. [144] In 2016, 3702 caffeine-related exposures were reported to Poison Control Centers in the United States, of which 846 required treatment at a medical facility, and 16 had a major outcome; and several caffeine-related deaths are reported in case studies. [144] The LD 50 of caffeine in rats is 192 milligrams per kilogram, the fatal dose in humans is estimated to be 150–200 milligrams per kilogram (2.2lb) of body mass (75–100 cups of coffee for a 70kg (150lb) adult). [145] [146] There are cases where doses as low as 57 milligrams per kilogram have been fatal. [147] A number of fatalities have been caused by overdoses of readily available powdered caffeine supplements, for which the estimated lethal amount is less than a tablespoon. [148] The lethal dose is lower in individuals whose ability to metabolize caffeine is impaired due to genetics or chronic liver disease. [149] A death was reported in 2013 of a man with liver cirrhosis who overdosed on caffeinated mints. [150] [151] Interactions Sherwood L, Kell R (2009). Human Physiology: From Cells to Systems (1st Canadianed.). Nelsen. pp.613–9. ISBN 978-0-17-644107-4.

Caffeine - Wikipedia Caffeine - Wikipedia

Grosso G, Micek A, Castellano S, Pajak A, Galvano F (January 2016). "Coffee, tea, caffeine and risk of depression: A systematic review and dose-response meta-analysis of observational studies". Molecular Nutrition & Food Research. 60 (1): 223–34. doi: 10.1002/mnfr.201500620. PMID 26518745.Temple JL, Bernard C, Lipshultz SE, Czachor JD, Westphal JA, Mestre MA (26 May 2017). "The Safety of Ingested Caffeine: A Comprehensive Review". Frontiers in Psychiatry. 8 (80): 80. doi: 10.3389/fpsyt.2017.00080. PMC 5445139. PMID 28603504. Structure of a typical chemical synapse Caffeine's primary mechanism of action is as an adenosine receptor antagonist in the brain.