Leptin

Leptin is a hormone produced by your fat cells that plays a key role in regulating appetite, metabolism, and body weight. Often called the satiety hormone, leptin signals to your brain when you've had enough to eat and helps regulate long-term energy balance. In some people, the brain becomes resistant to leptin's signals despite high levels of the hormone (leptin resistance), which is commonly linked to obesity. Measuring leptin can provide insights into metabolism, appetite regulation, and potential factors affecting weight management.