The primary function of fat in the body is to serve as a source of energy storage, insulation, and protection for vital organs. Fats, or lipids, are essential macronutrients that provide a high-energy yield, with 9 calories per gram. They help in absorbing fat-soluble vitamins (A, D, E, and K) and play a crucial role in hormone production and cell membrane structure. Besides energy storage, fats insulate the body to maintain temperature and cushion vital organs against trauma. A balanced intake of healthy fats is important for overall health and proper metabolic functioning.