Which hormone decreases appetite and promotes energy expenditure?

Leptin is the hormone that plays a pivotal role in regulating energy balance by inhibiting hunger, which in turn promotes energy expenditure. It is produced primarily by adipose (fat) tissue, and its levels are directly correlated with the amount of body fat; as fat stores increase, leptin levels rise. This hormone acts on specific receptors in the hypothalamus of the brain, signaling that the body has enough energy stored and thus reducing the desire to eat.

Leptin not only decreases appetite but also influences metabolism, leading to increased caloric burn. In individuals with obesity, however, there can be a resistance to the effects of leptin, which complicates effective appetite control and energy expenditure.

In contrast, while cortisol is a stress hormone that can influence metabolism and appetite, its primary role is not one of directly decreasing appetite or promoting energy expenditure. Growth hormone primarily influences growth and metabolism but does not directly decrease appetite as leptin does. Adiponectin, although it has roles in glucose regulation and fatty acid oxidation, mainly functions to enhance insulin sensitivity and does not have a strong direct effect on appetite suppression or energy expenditure compared to leptin.