Fifteen percent of the average woman's body weight is fat that provides readily accessible energy. Fat also serves a structural purpose. Approximately four percent of body weight is made up of fat in the organs, skeletal muscles, and central nervous systems. Having too little fat is a health hazard. There are gender differences in fat distribution.
Women tend to deposit fat on the thighs and buttocks while men deposit fat around the middle.
Women have higher concentrations of lipoprotein lipase in the thighs and buttocks while men have higher concentrations in the abdomen. The female pear and the male apple are broad generalizations. Many women may gain weight around the middle and some men may gain weight at the hips and thighs. There is a mountain of evidence that fat distribution is related to a person's hormonal levels. This tendency has been demonstrated in studies of women with polycystic ovary syndrome, a disorder characterized by relatively low concentrations of circulating estrogen.