What hormone is known to decrease hunger and increase satiety?

Leptin is a hormone that is primarily produced by adipose (fat) tissue. It plays a crucial role in regulating energy balance by signaling the brain about the body's fat stores. When fat stores increase, leptin levels rise, which helps to decrease appetite and increase feelings of fullness or satiety. This signaling is important for maintaining body weight and metabolic balance.

In contrast, the other hormones listed function in different ways. Insulin, while involved in glucose metabolism and blood sugar regulation, can also influence appetite but does not directly act to increase satiety in the same manner as leptin. Glucagon primarily works to raise blood glucose levels by promoting the release of glucose from the liver and does not have a role in decreasing hunger. Ghrelin, often referred to as the "hunger hormone," actually stimulates appetite and increases feelings of hunger, making it the opposite of leptin in terms of its effects on eating behavior.

Overall, the role of leptin as a satiety hormone is critical for understanding the physiological regulation of hunger and food intake.