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Sometimes referred to as liquid gold, coffee is the most popular source of caffeine in North America (and behind only teas worldwide). Also a source of tons of nutrients, and most recently touted as a source of chlorogenic acid and ferulic acid.

Our evidence-based analysis on coffee features 67 unique references to scientific papers.

Research analysis led by .
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Research Breakdown on Coffee

(Constituents found here[1])

  • Caffeine, sometimes at 1% total weight of coffee beans.[2]

  • Chlorogenic Acid, up to 7% total weight of coffee beans[2] but found to a higher level in Green coffee extract

  • Chlorogenic Lactone

  • Caffeic Acid

  • Nicotinic Acid

  • N-methylpyridinium compounds[3]

  • Cholinergic compounds

  • 5-Hydroxymethylfurfural (5-HMF)

  • Trigonelline, up to 1% of coffee beans by weight.[2]

  • Pyrogallol[4]

  • Catechol[4]

  • Melanodin structures, or small phenolics bound to sugars[5][6]

Beans also tend to have: 13% oil content by weight, 13% protein content by weight, 15% hemicellulose and 18% holocellulose, 2% lignan, 4% ash, 3% pectin, 7% sucrose and 1% reducing sugars.[2]

Doses of all compounds vary on bean quality, length to initiation of processing, type of processing and preparation method, and length of time processed.


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  2. ^ a b c d Ramalakshmi K, Raghavan B. Caffeine in coffee: its removal. Why and how. Crit Rev Food Sci Nutr. (1999)
  3. ^ Kotyczka C, et al. Dark roast coffee is more effective than light roast coffee in reducing body weight, and in restoring red blood cell vitamin E and glutathione concentrations in healthy volunteers. Mol Nutr Food Res. (2011)
  4. ^ a b Rubach M, et al. Multi-parametric approach to identify coffee components that regulate mechanisms of gastric acid secretion. Mol Nutr Food Res. (2012)
  5. ^ Moreira AS, et al. Coffee melanoidins: structures, mechanisms of formation and potential health impacts. Food Funct. (2012)
  6. ^ Fogliano V, Morales FJ. Estimation of dietary intake of melanoidins from coffee and bread. Food Funct. (2011)
  7. Kempf K, et al. Effects of coffee consumption on subclinical inflammation and other risk factors for type 2 diabetes: a clinical trial. Am J Clin Nutr. (2010)
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  11. Fox GP, et al. Variation in caffeine concentration in single coffee beans. J Agric Food Chem. (2013)
  12. McCusker RR, Goldberger BA, Cone EJ. Caffeine content of specialty coffees. J Anal Toxicol. (2003)
  13. Angeloni G, et al. What kind of coffee do you drink? An investigation on effects of eight different extraction methods. Food Res Int. (2019)
  14. Noordzij M, et al. Blood pressure response to chronic intake of coffee and caffeine: a meta-analysis of randomized controlled trials. J Hypertens. (2005)
  15. World Health Organization. The ICD-10 classification of mental and behavioural disorders: clinical descriptions and diagnostic guidelines.
  16. Juliano LM, et al. Characterization of individuals seeking treatment for caffeine dependence. Psychol Addict Behav. (2012)
  17. EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA). Safety of caffeine. EFSA Journal. (2015)
  18. Food and Nutrition Board. Caffeine in Food and Dietary Supplements: Examining Safety: Workshop Summary.. The National Academies Press. (2014)
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  20. Committee on Military Nutrition Research, Food and Nutrition Board. Caffeine for the Sustainment of Mental Task Performance: Formulations for Military Operations.
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  27. Arria MA, et al. Letter to Commissioner Hamburg Re: The Use of Caffeine in Energy Drinks.
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  29. Poole R, et al. Coffee consumption and health: umbrella review of meta-analyses of multiple health outcomes. BMJ. (2017)
  30. Voskoboinik A, Kalman JM, Kistler PM. Caffeine and Arrhythmias: Time to Grind the Data. JACC Clin Electrophysiol. (2018)
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  42. Rogers PJ, et al. Association of the anxiogenic and alerting effects of caffeine with ADORA2A and ADORA1 polymorphisms and habitual level of caffeine consumption. Neuropsychopharmacology. (2010)
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  44. Barry RJ, Clarke AR, Johnstone SJ. Caffeine and opening the eyes have additive effects on resting arousal measures. Clin Neurophysiol. (2011)
  45. Haskell CF, et al. Cognitive and mood improvements of caffeine in habitual consumers and habitual non-consumers of caffeine. Psychopharmacology (Berl). (2005)
  46. Rogers PJ, et al. Absence of reinforcing, mood and psychomotor performance effects of caffeine in habitual non-consumers of caffeine. Psychopharmacology (Berl). (2003)
  47. Pontifex KJ, et al. Effects of caffeine on repeated sprint ability, reactive agility time, sleep and next day performance. J Sports Med Phys Fitness. (2010)
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  50. Schneiker KT, et al. Effects of caffeine on prolonged intermittent-sprint ability in team-sport athletes. Med Sci Sports Exerc. (2006)
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  52. Cook C, et al. Acute caffeine ingestion increases voluntarily chosen resistance training load following limited sleep. Int J Sport Nutr Exerc Metab. (2012)
  53. Del Coso J, et al. Dose response effects of a caffeine-containing energy drink on muscle performance: a repeated measures design. J Int Soc Sports Nutr. (2012)
  54. Mora-Rodríguez R, et al. Caffeine ingestion reverses the circadian rhythm effects on neuromuscular performance in highly resistance-trained men. PLoS One. (2012)
  55. Astorino TA, et al. Effect of two doses of caffeine on muscular function during isokinetic exercise. Med Sci Sports Exerc. (2010)
  56. Pedersen DJ, et al. High rates of muscle glycogen resynthesis after exhaustive exercise when carbohydrate is coingested with caffeine. J Appl Physiol (1985). (2008)
  57. Kim TW, et al. Caffeine increases sweating sensitivity via changes in sudomotor activity during physical loading. J Med Food. (2011)
  58. Astrup A, et al. Caffeine: a double-blind, placebo-controlled study of its thermogenic, metabolic, and cardiovascular effects in healthy volunteers. Am J Clin Nutr. (1990)
  59. Acheson KJ, et al. Metabolic effects of caffeine in humans: lipid oxidation or futile cycling?. Am J Clin Nutr. (2004)
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  65. Li M, et al. The effect of caffeine on intraocular pressure: a systematic review and meta-analysis. Graefes Arch Clin Exp Ophthalmol. (2011)
  66. Chandrasekaran S, Rochtchina E, Mitchell P. Effects of caffeine on intraocular pressure: the Blue Mountains Eye Study. J Glaucoma. (2005)
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