Leptin is often called the “satiety hormone” because it helps your brain regulate long-term hunger and energy balance. It’s made by your fat cells and acts like a messenger, telling your brain when you’ve had enough to eat. When leptin levels are high, it’s supposed to signal fullness and help your body burn calories more efficiently.
But here’s the catch: people with obesity often have high levels of leptin, yet their brains don’t respond to it properly. This condition is called leptin resistance. According to the Centers for Disease Control and Prevention (CDC), more than 1 in 5 U.S. adults are obese. For many, hormonal imbalances like leptin resistance may be part of the reason why losing weight feels so difficult.
If your body isn’t responding to leptin properly, it may keep sending hunger signals even when you’ve eaten enough. That means you might feel hungry more often, crave high-calorie foods and struggle to lose weight even if you’re following a healthy diet and exercising regularly.
How leptin helps manage your weight
Leptin is produced by fat cells, and its levels change depending on how much energy your body is taking in and using. When you eat more and store fat, leptin levels go up. When you eat less and lose fat, leptin levels go down.
Unlike hormones that affect hunger from meal to meal, leptin works over time to help your body maintain a healthy weight. It helps regulate how much energy you burn and how hungry you feel in the long run.
But leptin doesn’t work alone. Things like poor sleep, high stress and inflammation can affect how well leptin does its job. An article published in Frontiers in Physiology shows that leptin is part of a complex system that helps your body stay in balance. When that system is disrupted, it can lead to weight gain and other health issues.
What is leptin resistance?
Leptin resistance happens when your brain stops responding to leptin’s signals—even though there’s plenty of leptin in your body. It’s like your brain has stopped listening to the hormone that’s supposed to tell it you’re full.
When this happens, your body may think it’s starving, even if you have enough fat stored. This can lead to:
- Constant hunger
- Difficulty losing weight
- Fatigue
- Cravings for sugary or fatty foods
Leptin resistance is often compared to insulin resistance, another condition where the body ignores important hormonal signals. Both can make it harder to manage weight and overall health.
What causes leptin resistance?
Several lifestyle factors can lead to leptin resistance. These include:
- Diets high in sugar and processed foods
- Chronic stress
- Poor sleep habits
- Lack of physical activity
Just like with insulin resistance, changing these habits can help improve leptin sensitivity. The American Heart Association notes that high levels of stress hormones are linked to increased risk of metabolic and heart problems, which may also affect how leptin works in your body.
Can leptin resistance be treated?
Right now, there are no FDA-approved medications specifically for leptin resistance. But the good news is that healthy lifestyle changes can make a big difference. These include:
- Regular physical activity
- Eating a balanced diet with whole foods
- Getting enough quality sleep
- Managing stress through mindfulness or relaxation techniques
If you think leptin resistance might be affecting your health, it’s important to talk to a healthcare provider. They can help you create a personalized plan to improve your metabolic health.
How to test your leptin levels
Want to learn more about your hormone health? Labcorp OnDemand offers a Leptin Test that measures your leptin levels and may provide insights into your metabolic health. You can also explore Labcorp’s Weight Management Tracking Test, which looks at other markers that affect weight and metabolism.
Always consult with a healthcare provider to interpret your results and determine next steps.
