How Does 2-Minute Neuroscience: Leptin & Ghrelin Work?

Imagine your body has two special messengers that tell you when to eat and when to stop, leptin and ghrelin.

Think of leptin like a bell that rings when your tummy is full. It’s made by your fat cells, so the more fat you have, the louder the bell gets. When the bell rings, it says, “Hey, I’m full, time to stop eating!”

Now imagine ghrelin as a little friend who comes running to your side when your tummy is empty. It’s made in your stomach, and it gives you that “I’m hungry” feeling. Ghrelin is like the timer on your microwave, it goes off when it's time for another snack.

When you eat, your stomach gets full, and leptin sends a message to your brain: “Enough food, I'm happy!” At the same time, ghrelin levels go down because it’s saying, “I’m not hungry anymore.”

But when you haven’t eaten for a while, ghrelin goes up again like a little friend shouting, “I want more snacks!” And your brain listens.

So, leptin and ghrelin are like the on-and-off switch of your hunger, one says "stop," and the other says "go!"