As the name suggests, this type of fat is necessary for a healthy life and body. Essential fats are found in the brain, bone marrow, nerves and membranes that protect the body's organs. This type of fat is responsible for the regulation of hormones that control fertility, vitamin absorption, and temperature regulation. According to the American Council on Exercise, a woman is considered healthy if 10 to 13 percent of her body composition comes from essential fats, while for men 2 to 5 percent.