The teen years are practically synonymous with hormones. But there’s one place hormones show up that often gets overlooked: appetite. 

The sensations of hunger and satiety (feeling full) are influenced by two hormones called Leptin and Ghrelin. (Sounds like two characters from a Star Wars sequel, right?)

Ghrelin is the hormone that makes you want to eat. When the tank is empty, Ghrelin signals: “We’re hungry.” Leptin, on the other hand, tells your body to stop eating when the tank is full.

These two work together like a team to regulate appetite. When one goes up, the other goes down, balance. But we all know how tricky balance can be.

Leptin Resistance

This next part can feel a bit like algebra, and it involves fat cells. But before we dive in, let’s be clear: the human body needs fat.

Fat cells aren’t just storage for energy. They’re also endocrine organs, meaning they release hormones, including these important hunger hormones. But when there’s an overload of fat cells, those signals can get scrambled. Here’s how it works:

You’d assume that the more fat cells a body has, the more leptin (the “I’m full” hormone) it produces, helping regulate appetite and prevent overeating. In turn, ghrelin (the “I’m hungry” hormone) should drop. So technically, more fat = less hunger, right?

Not quite.

When leptin is overproduced, the brain can develop leptin resistance, it stops “hearing” the leptin signals, much like a parent who tunes out a noisy toy after a while. Without leptin’s message getting through, ghrelin keeps rising unchecked. The result? Constant hunger, even with plenty of stored fat, which can lead to overeating and, you guessed it, more fat storage.

Why this matters for teenagers

Childhood and adolescence are crucial growth periods when fat cells don’t just grow in size, they can multiply. Once new fat cells are created, they typically stick around for life, even if the person loses weight later on. This can “confuse” leptin signals early, making it harder for teens to regulate hunger without understanding or support.

Finding the Balance: What Parents Can Do

The goal isn’t to control every bite your teen eats. It’s to help their natural hunger and fullness signals (leptin and ghrelin) work as they should. The good news? Small, steady habits make a big difference.

• Prioritise real food: Balanced meals with protein, fibre, and healthy fats help keep hunger steady and satiety signals clear.
• Protect sleep: A tired teen produces more ghrelin and less leptin, making cravings harder to resist.
• Keep routines simple: Regular meals and snacks help stabilise appetite and prevent overeating from extreme hunger.
• Model the mindset: Teens absorb what you say about your own body and food, show them that nourishment, not numbers, matters most.
• Stay connected: If you notice food being used as a coping tool, open gentle conversations and – when needed – lean on professional support.

Final thoughts

Helping your teen listen to their body is a long-term gift. When leptin and ghrelin are in balance, food becomes fuel, meals become moments, and health becomes a natural rhythm, not a struggle.