For example, when your stomach is empty, specialized cells in the stomach wall produce a hormone called ghrelin, which travels via your bloodstream or signals via the vagus nerve to your brain, where it triggers a strong urge to eat. On the other hand, when you’re satiated and your small intestine is busy digesting your food, cells there release “satiety” hormones that tell your brain that you’re full and it’s time to call a halt to further eating.
