Caffeine

Caffeine, a bitter alkaloid, is a psychoactive stimulant that is found naturally in varied amounts in more than 60 plants, including coffee beans, tea leaves, kola nuts, cacao pods, and yerba maté. It is also synthesized for use as a food additive and in drugs. It is most commonly consumed throughout the world in beverages such as coffee, tea, soft drinks, and energy drinks. Amounts of caffeine in a 5-oz (150-mL) serving of these beverages range from 70 to 220 mg for coffee, 32 to 42 mg for tea, and 32 to 70 mg for a larger 11-oz serving of cola. The average daily intake from all sources in the United States and Canada is 210 to 239 mg but may be double that in ...