Decaf is not the same as caffeine-free. The FDA says decaffeinated coffees and teas have less caffeine than their regular counterparts but still contain some. If you react strongly to caffeine in a negative way, the agency says you may want to avoid these drinks altogether.

That matters because people differ a lot. The FDA says there is wide variation in both how sensitive people are to caffeine's effects and how fast their bodies eliminate it. The agency also says there is no difference in how your body handles caffeine that occurs naturally in coffee and tea versus caffeine added to a product, so it helps to count every source.

Labels can help, up to a point. The FDA says packaged foods must list caffeine in the ingredients when it is added as a stand-alone ingredient. When an ingredient such as chocolate naturally contains caffeine, only that ingredient appears on the list. Many packaged foods and drinks voluntarily state how much caffeine they contain, but restaurants and other retail food sellers are not required by law to tell you. The FDA encourages you to ask.

If you drink caffeinated beverages every day and want to cut back, the FDA says it is best to do so gradually. Caffeine withdrawal is not considered dangerous, the agency says, but it can be unpleasant. If you are unsure how caffeine fits with your health or your medicines, talk to your doctor.