Ghrelin is a hormone produced primarily in the stomach that sends hunger signals to the brain. It’s sometimes called the ‘hunger hormone’ because levels rise before meals and fall after eating.
What Ghrelin Does:
When your stomach is empty, it releases ghrelin, which travels to the hypothalamus in the brain to stimulate appetite and trigger the feeling of hunger. This encourages you to seek food. After eating, ghrelin levels drop, and other hormones (like leptin) signal fullness.
Ghrelin and Sleep:
Sleep deprivation significantly increases ghrelin levels, which is one reason why lack of sleep is associated with increased appetite and weight gain. When you’re tired, your body produces more ghrelin, making you feel hungrier even if you don’t need more calories.
The Hunger-Satiety Balance:
Ghrelin works in opposition to leptin and other satiety hormones. In a well-regulated system, ghrelin rises before meals, prompts you to eat, then drops afterward while satiety hormones rise. Chronic stress, poor sleep, and restrictive dieting can disrupt this delicate balance.
