Take Home Points:




caffeine_structure Figure 1. Chemical structure of caffeine (1,3,7-trimethylxanthine).

How to Take

Effects on the Brain

Effects on the brain are outlined below.




Side Effects

Effects on the Body

Exercise Performance

Physiological Parameters


Approved as a dietary supplement component under provisions of the Dietary Supplement Health and Education Act of 1994.

Check out this caffeine calculator at caffeine informer to get an estimate of the amount of caffeine safe to consume based on your weight. See table 2 for an estimate of the caffeine content in common foods and drinks.

caffeine_content_food_drink Table 2. Caffeine content of select foods and drinks.

Effects on Disease States

Caffeine & L-theanine

Caffeine and L-theanine can act synergistically to improve alertness and attention. L-theanine can also potentially reverse some of the less favorable physiological effects of caffeine - including increased blood pressure, and reduced flow of oxygenated blood to the head. (Learn more)

  1. Fredholm, B. B., Battig, K., Holmen, J., Nehlig, A., & Zvartau, E. E. (1999). Actions of caffeine in the brain with special reference to factors that contribute to its widespread use. Pharmacol Rev, 51(1), 83-133. Retrieved from

  2. Johnson, L. C., Spinweber, C. L., & Gomez, S. A. (1990). Benzodiazepines and caffeine: effect on daytime sleepiness, performance, and mood. Psychopharmacology (Berl), 101(2), 160-167.

  3. Smith, A., Kendrick, A., Maben, A., & Salmon, J. (1994). Effects of breakfast and caffeine on cognitive performance, mood and cardiovascular functioning. Appetite, 22(1), 39-55. doi:10.1006/appe.1994.1004

  4. Smith, A. P., Kendrick, A. M., & Maben, A. L. (1992). Effects of breakfast and caffeine on performance and mood in the late morning and after lunch. Neuropsychobiology, 26(4), 198-204. doi:118920

  5. Smith, B. D., Davidson, R. A., & Green, R. L. (1993). Effects of caffeine and gender on physiology and performance: further tests of a biobehavioral model. Physiol Behav, 54(3), 415-422.

  6. Wilhelmus, M. M., Hay, J. L., Zuiker, R. G., Okkerse, P., Perdrieu, C., Sauser, J., ... & Silber, B. Y. (2016). Effects of a single, oral 60 mg caffeine dose on attention in healthy adult subjects. Journal of Psychopharmacology, 0269881116668593.

  7. Warburton, D. M. (1995). Effects of caffeine on cognition and mood without caffeine abstinence. Psychopharmacology (Berl), 119(1), 66-70.

  8. Smith, A. P., Christopher, G., & Sutherland, D. (2013). Acute effects of caffeine on attention: a comparison of non-consumers and withdrawn consumers. J Psychopharmacol, 27(1), 77-83. doi:10.1177/0269881112460112

  9. Rogers, P. J., Smith, J. E., Heatherley, S. V., & Pleydell-Pearce, C. W. (2008). Time for tea: mood, blood pressure and cognitive performance effects of caffeine and theanine administered alone and together. Psychopharmacology (Berl), 195(4), 569-577. doi:10.1007/s00213-007-0938-1

  10. Einother, S. J., & Giesbrecht, T. (2013). Caffeine as an attention enhancer: reviewing existing assumptions. Psychopharmacology (Berl), 225(2), 251-274. doi:10.1007/s00213-012-2917-4

  11. Lieberman, H. R., Tharion, W. J., Shukitt-Hale, B., Speckman, K. L., & Tulley, R. (2002). Effects of caffeine, sleep loss, and stress on cognitive performance and mood during U.S. Navy SEAL training. Sea-Air-Land. Psychopharmacology (Berl), 164(3), 250-261. doi:10.1007/s00213-002-1217-9

  12. Leathwood, P. D., & Pollet, P. (1982). Diet-induced mood changes in normal populations. J Psychiatr Res, 17(2), 147-154.

  13. Morgan, A., & Stevens, J. (2010). Does Bacopa monnieri improve memory performance in older persons? Results of a randomized, placebo-controlled, double-blind trial. The Journal of Alternative and Complementary Medicine, 16(7), 753-759.

  14. Smith, A. (2002). Effects of caffeine on human behavior. Food Chem Toxicol, 40(9), 1243-1255.

  15. Burke, T. M., Markwald, R. R., McHill, A. W., Chinoy, E. D., Snider, J. A., Bessman, S. C., . . . Wright, K. P., Jr. (2015). Effects of caffeine on the human circadian clock in vivo and in vitro. Sci Transl Med, 7(305), 305ra146. doi:10.1126/scitranslmed.aac5125

  16. Van Dam, R. M., Pasman, W. J., & Verhoef, P. (2004). Effects of Coffee Consumption on Fasting Blood Glucose and Insulin Concentrations. Diabetes care, 27(12), 2990-2992.

© 2017 HVMN, Inc. All Rights Reserved.

For informational purposes only. These statements have not been evaluated by the FDA. Products are not intended to diagnose, treat, cure, or prevent any disease.