Our bodies need fat for many reasons and there are probably some we are not readily aware of. We know that fat adds flavor to our foods and helps to keep food in our stomachs longer so we don't get hungry right after eating. Fat assists the body with the absorption of these fat soluble vitamins like A, E, S, and K and keep us from having a deficiency of these vitamins. Fat also provides an energy back-up when we use up the sugar in our blood which can happen if we don't eat for 4 to 6 hours. The fat already stored in our bodies provides us with needed insulation when the temperature is cold or hot. So fat really is needed by the body but when we eat more than our body needs or uses we gain weight.