To peel or not to peel the apple? Research from the University of Iowa suggests that a natural substance found in the peel of apples can partially protect mice fed a high-fat diet from obesity, pre-diabetes, and fatty liver disease. This substance, ursolic acid, contributes to the waxy coats on apples and many herbs. The investigators were surprised to discover that ursolic acid increases "brown fat," a type of fat that actually burns calories. Further research is necessary to determine if the same phenomenon occurs in humans.
PositiveTip: Eat the apple and the peel for good health.