The American Council on Exercise (ACE) tells us that "A healthy body represents a healthy body composition". So in essence, the makeup of your body plays an integral role of its overall internal functioning. Body composition is comprised of two general components, your body fat and your non-fat body mass (ie: organs, muscle mass, skeleton, etc)
A big part of getting and maintaining a healthy body composition is keeping your body's fat levels under control while making sure that the non-fat parts of you are strong and in full working order at all times. A healthy body composition for women is considered to be between 21% and 24% fat, with the rest non fat. The range for a man's healthy body composition runs from about 14% to 17% body fat.