About 400 mg of Caffeine a Day Is Fine for Most Adults

Coffee drinkers often wonder how much is too much. The U.S. Food and Drug Administration gives a figure. For most adults, the FDA has cited 400 milligrams a day, about two to three 12-fluid-ounce cups of coffee, as an amount not generally associated with negative effects. People differ, though, and the FDA notes that it is important to know whether a product has caffeine, especially if you are sensitive to it or are giving it to children or teens. Decaf is not zero. Decaf coffee typically has 2 to 15 milligrams in an 8-fluid-ounce cup. Younger people get different advice. Medical experts advise against energy drinks for children and teens, and the Dietary Guidelines for Americans say drinks containing caffeine should be avoided for children younger than 2. In children and teens, the FDA notes, too much caffeine can cause an increased heart rate, anxiety and sleep problems.