Common Effects of Caffeine

10. High Caffeine Foods and Beverages

Coffee is high in caffeine. Even decaf coffee has about the same amount of caffeine as green tea. Some stronger teas, such as black or Earl Grey, have higher amounts of caffeine, while herbal teas are caffeine-free and can serve as a substitute. Almost all sodas have caffeine, as well -- furthermore, the high sugar content can exacerbate some of caffeine's effects. Chocolate also has plenty of caffeine, with dark chocolate (which contains less sugar and milk) having the highest concentration. Caffeine supplements are available over the counter, as well -- be sure to read the package to determine the correct amount for your body and tolerance.

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