fat [%PREMIUM_LINK%] (fāt) Pronunciation Key |
Any of a large number of oily compounds that are widely found in plant and animal tissues and serve mainly as a reserve source of energy. In mammals, fat, or adipose tissue, is deposited beneath the skin and around the internal organs, where it also protects and insulates against heat loss. Fat is a necessary, efficient source of energy. An ounce of fat contains more than twice as much stored energy as does an ounce of protein or carbohydrates and is digested more slowly, resulting in the sensation of satiety after eating. It also enhances the taste, aroma, and texture of food. Fats are made chiefly of triglycerides, each molecule of which contains three fatty acids. Dietary fat supplies humans with essential fatty acids, such as linoleic acid and linolenic acid. Fat also regulates cholesterol metabolism and is a precursor of prostaglandins. See more at saturated fat, unsaturated fat.