The caffeine in coffee can speed up the metabolism. In nutritional circles, it’s known as a metabolic enhancer, according to Dr. Judith Stern of the University of California at Davis.
This makes sense, since caffeine is a stimulant. Studies show it can help you burn more calories than normal, perhaps up to 10 percent more. For safety’s sake, it’s best to limit your intake to a single cup in the morning and one in the afternoon. Add only skim milk to tit and try doing without sugar – many people learn to love it that way.