Caffeine

other Unit: mg

Caffeine is a naturally occurring methylxanthine and the world's most widely consumed psychoactive compound. It works primarily by blocking adenosine receptors in the brain, promoting alertness and reducing perceived fatigue. Moderate intake — up to 400 mg per day for healthy adults — is generally recognized as safe; higher amounts can cause anxiety, elevated heart rate, and sleep disruption. Coffee, tea, energy drinks, and chocolate are the main dietary sources.

Reference Daily Intake · per 100g

USDA/NIH DRI · National Academies

Top 20 Foods by Caffeine

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Reference Daily Intake

No established RDA for this nutrient.