What are the benefits of caffeine?

Caffeine's effects (and hence those of guaranine) are well known. It stimulates the central nervous system, increasing metabolic rate, and has a mild diuretic effect.¹ One recent research study showed that caffeine consumption may have benefits for performance and safety in the workplace.² The results of another study showed that caffeine may modulate a higher brain function through its effects on distinct areas of the brain, particularly as it relates to working memory.³ Working memory represents the type of brain activity needed to remember things for a short period of time such as looking at a phone number and mentally storing it until it's been dialed. While all of these results are promising, the research does not suggest increased consumption of what is considered normal just yet.

¹ Leung A Y, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs, and Cosmetics, 2d ed. New York: John Wiley & Sons, 1996, 293-94. ² Smith A P. Caffeine at work. Human Psychopharmacology 2005; 20 (6): 441-5. ³ Influences of Caffeine Excess on Activation Patterns in Verbal Working Memory, study results presented at the annual meeting of the Radiological Society of North America (RSNA), 2005. *If you are pregnant or nursing consult with your health care provider before using caffeine or guaranine.