Which hormone regulates hunger in the human body?

The hormone that regulates hunger in the human body is ghrelin. It is produced primarily by specialized enteroendocrine cells in the gastrointestinal tract, especially in the stomach, and it signals the brain to increase appetite.

Ghrelin levels commonly rise before meals and fall after eating. In the brain, it acts on areas including the hypothalamic arcuate nucleus, stimulating pathways that promote food intake. It also affects gastric motility and the secretion of gastric acid, helping prepare the digestive system for food.

Leptin also participates in appetite regulation, but it generally signals long-term energy stores and contributes to satiety. Insulin influences blood glucose and can affect appetite, while cortisol is primarily involved in stress and metabolism.

Because the question asks specifically about hunger, ghrelin is the canonical answer. Its common nickname, “the hunger hormone,” directly reflects its appetite-stimulating role.