Hunger Hormones & Insulin: Why You’re Always Hungry
If you’ve ever felt like your hunger is out of control, you’re not alone. Appetite isn’t just about willpower—it’s controlled by hormones. Your body has an entire system of hunger and fullness signals designed to regulate how much you eat and when. The problem? Insulin plays a major role in how these appetite hormones work, and when insulin is high or dysregulated, your hunger signals get completely out of balance.
This is why so many people struggle with constant cravings, extreme hunger, and feeling like they’re never truly satisfied after meals. It’s not a lack of discipline—it’s a hormonal issue that can only be fixed by getting insulin under control.
Let’s break down the key appetite hormones, what they do, and how insulin affects them.
1. Ghrelin: The Hunger Hormone
Ghrelin is your body’s main hunger signal. It’s produced in the stomach and tells your brain that it’s time to eat. When ghrelin rises, you feel hungry. After eating, ghrelin drops, signaling that you’re full.
How Insulin Affects Ghrelin:
When insulin is high, ghrelin doesn’t drop properly after eating. This means that even after a meal, you may still feel hungry because your body hasn’t registered that you’ve eaten enough.
Ever eaten a big meal and still felt like you could eat more? That’s insulin blunting your ghrelin response. This is especially common when meals are high in starch and sugar, which spike insulin and interfere with normal hunger regulation.
✔ How to Fix It: Keep insulin low by eating meals rich in protein, healthy fats, and fiber. This helps ghrelin respond properly, so you actually feel full after meals.
2. Leptin: The Fullness Hormone
Leptin is the hormone that tells your brain, “I have enough energy, stop eating.” It’s produced by your fat cells and helps regulate metabolism and appetite. More body fat = more leptin, which should mean more appetite control.
How Insulin Affects Leptin:
When insulin is chronically high, it blocks leptin signals in the brain—a condition known as “leptin resistance.”
This means your brain doesn’t “hear” the fullness signals leptin is sending, so it keeps telling you to eat, even when you don’t need more food. This is why people with insulin resistance often feel like they are always hungry, even when they are overweight. Their brain isn’t responding to leptin the way it should.
✔ How to Fix It: Lowering insulin restores leptin sensitivity, allowing your body to recognize fullness again. Through lowering insulin levels, a Low Insulin Lifestyle helps regulate leptin levels so your brain actually gets the message when you’ve had enough food.
3. GLP-1: The Natural Appetite Suppressant
GLP-1 (glucagon-like peptide-1) is a hormone that slows digestion, reduces appetite, and promotes satiety. It’s one of the reasons why you feel full longer after eating protein and fiber-rich foods. GLP-1 is also the hormone that GLP-1 medications like Ozempic, Wegovy, and Mounjaro are designed to mimic.
How Insulin Affects GLP-1:
Chronically high insulin levels blunt GLP-1’s appetite-suppressing effects. This is why some people feel hungry just an hour or two after eating a meal high in processed carbs—their body isn’t producing enough GLP-1 to keep them satisfied.
✔ How to Fix It: Protein, fiber, and healthy fats naturally stimulate GLP-1, while avoiding high insulin spikes helps keep it functioning properly. This is why eating an insulin-friendly diet naturally reduces hunger and cravings without the need for medications.
4. CCK: The Fat-Digesting Hormone That Keeps You Satisfied
CCK (cholecystokinin) is released when you eat fat and protein, and it tells your brain, “You’re full.” It also helps slow digestion so you feel satisfied longer after meals.
How Insulin Affects CCK:
When insulin is chronically high, CCK levels are disrupted, leading to reduced satiety signals. If your body isn’t registering CCK properly, you might feel like you need to keep eating, even if you’ve already had enough.
✔ How to Fix It: Eating enough healthy fats and proteins supports CCK production and improves satiety. Low-fat, high-carb diets disrupt CCK and lead to constant hunger, which is why eating enough fat is key for long-term appetite control.
5. Cortisol: The Stress Hormone That Triggers Cravings
Cortisol isn’t technically an appetite hormone, but it plays a huge role in hunger and cravings. When cortisol is high, it increases insulin and triggers intense cravings for sugar and processed carbs. This is why stress eating is so common—your body is literally pushing you to eat high-carb foods to deal with stress.
How Insulin Affects Cortisol:
High insulin levels keep cortisol elevated, and high cortisol keeps insulin elevated. It’s a vicious cycle that leads to more cravings, more stress eating, and more fat storage—especially around the belly.
✔ How to Fix It: Keeping insulin stable helps regulate cortisol. Managing stress through sleep, walking, and proper nutrition can help prevent cortisol-driven hunger and cravings.
Why a Low Insulin Lifestyle Balances Your Appetite Hormones
When insulin is too high, your hunger and fullness hormones get thrown off. You feel hungrier than you should, less satisfied after eating, and more likely to overeat—especially in a calorie deficit.
By keeping insulin low and stable, you allow ghrelin, leptin, GLP-1, and CCK to function properly. This means:
- You actually feel full after meals.
- Your cravings decrease.
- You no longer feel like you’re starving between meals.
- Your body learns to regulate food intake naturally.
The best part? This happens without counting calories or forcing yourself to restrict. Your body simply starts working the way it was designed to.
The Bottom Line
Hunger and cravings aren’t about willpower—they’re about hormones. When insulin is high, appetite hormones get out of balance, leading to constant hunger, cravings, and difficulty losing weight.
By following a Low Insulin Lifestyle, you allow these hormones to reset, making it easier to eat the right amount naturally—without the constant struggle. Hunger becomes manageable, fullness actually lasts, and your body starts working with you instead of against you.
References
Lim GE, Huang GJ, Flora N, LeRoith D, Rhodes CJ, Brubaker PL. Insulin regulates glucagon-like peptide-1 secretion from the enteroendocrine L cell. Endocrinology. 2009. Read more
Kumar R, Mal K, Razaq MK, Magsi M, Memon MK, Memon S, Afroz MN, Siddiqui HF, Rizwan A. Association of Leptin With Obesity and Insulin Resistance. Cureus. 2020. Read more
Ziemke F, Mantzoros CS. Adiponectin in insulin resistance: lessons from translational research. Am J Clin Nutr. 2010 Jan;91(1):258S-261S. doi: 10.3945/ajcn.2009.28449C. Epub 2009. Read more
