Energy Drinks Can Hold Up to 328 mg of Caffeine per Can

The words energy drink tell you little about how much caffeine is inside. The U.S. Food and Drug Administration states that energy drinks generally have 54 to 328 milligrams of caffeine per 16 fluid ounces, with a few brands containing 41 to 246 milligrams per 12 fluid ounces. The top of that range is close to the 400 milligrams a day that the FDA cites as an amount not generally associated with negative effects for most adults. The name itself, the FDA notes, was developed by the food industry to describe certain beverages, and the agency has no regulation specific to energy drinks. General rules on the safe use of ingredients still apply. Most energy drinks sold in the United States list the total caffeine from all sources on the label, including ingredients such as guarana that also contain caffeine.