What is the primary function of leptin?

Leptin is a hormone produced primarily by adipose (fat) tissue, and its main role is to regulate energy balance in the body. It serves as a key signal to the hypothalamus regarding the amount of fat stored in the body. When fat stores are sufficient, leptin levels increase, which communicates to the brain to reduce appetite and increase energy expenditure. This mechanism helps prevent overeating and promotes a stable body weight.

In addition to inhibiting hunger, leptin also plays a role in the regulation of various metabolic processes, leading to a decrease in appetite and an increase in the metabolic rate. This makes it a crucial factor in maintaining energy homeostasis.

The other options suggest functions or effects that do not accurately reflect leptin's primary role. For example, stimulating insulin secretion, promoting fat storage, or increasing appetite reflect the activities of other hormones and signals in the body rather than those of leptin. Thus, the correct focus is on leptin's function in managing energy balance and inhibiting hunger.