Sex Steroids Regulation of Appetitive Behavior

Appetite is the desire to satisfy the need to consume food, felt as hunger. It is regulated by the balance of food intake and energy expenditure via signals between the brain, the digestive tract and the adipose tissue. Males and females vary in terms of eating behavior as well as the way the body fat is stored. Energy balance and body fat distribution are part of the sexual dimorphism in many mammalian species including human beings. These sex dissimilarities could be related to the different sex steroid hormone profile in each sex. Gonadal steroid hormones play an important role in the regulation of food intake and energy homeostasis. Human epidemiological and experimental animal studies have shown that estradiol has a key role in the control of food intake and energy balance. Estradiol has long been known to inhibit feeding in animals. There are important changes in food intake patterns during the estrous cycle, with a reduction of food intake around the time of ovulation, when estradiol presents its highest levels. Men have less total fat and more central fat distribution which carries a much greater risk for metabolic disorders while women have more total fat and more gluteal/femoral subcutaneous fat distribution. Men and postmenopausal women accumulate more fat in the intra-abdominal depot. This review is focused on the mechanism by which sex steroids affect feeding behavior and fat distribution.