One of the benefits of drinking Coke is that it contains caffeine, a natural stimulant found in the kola nut, coffee beans and tea leaves. Caffeine makes you feel more alert when you're tired and might increase your performance when embarking on certain tasks. According to the International Food Council Information Foundation, the U.S. Food and Drug Administration, or FDA, has recognized caffeine as an additive that's Generally Recognized As Safe, or GRAS, since the late 1950s. Moderate consumption of caffeine -- around 300 mg -- is generally not harmful for healthy adults, although some people are more sensitive to caffeine. A 12 oz. can of Coke contains 34 mg of caffeine, far less than the average cup of coffee, which contains 85 mg of caffeine.