Questions & Answers: What are caffeine's effects?

Q. What are caffeine's psychological benefits and risks?

A. Caffeine is the most widely used psychoactive drug in the world. Up to 90% of Americans take it regularly, usually in the form of coffee, tea, or soft drinks, sometimes in a tablet (No-Doz and others). The average daily dose, 300 mg, is the equivalent of three cups of coffee. No wonder selling expensive caffeinated drinks is good business!

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