All hormones play a crucial role in your body, but there is one that holds the skeleton key and is considered the master: Leptin.
You may have heard of leptin called the "satiety hormone" or "starvation hormone." It controls all energy metabolism in your body, and plays a significant role in fertility, immunity and brain function.
In fact, it influences all other hormones in the body. It is the sine qua non for optimizing your body composition, energy levels, and overall performance.
How Leptin Works
Leptin is released from your adipose tissues and signals your hypothalamus about your body's energy status. The more body fat you carry, the more leptin you produce.
Your bloodstream carries leptin into your brain, where it sends a signal to the hypothalamus, which controls when and how much you eat.
High levels of leptin tell your brain that you have plenty of fat stored. Low levels of leptin tell your brain that fat stores are low and you need to eat.
Because of this direct connection from white fat stores to your brain, leptin regulates long-term food intake, energy expenditure, and helps maintain your body weight.
And since your brain is responsible for receiving and delivering energy status from over 20 trillion cells in your body, signaling efficiency is pretty important. When it's poor or broken, problems arise.
Leptin Resistance
If your brain no longer recognizes the leptin signal sent to the brain, you become leptin resistant. This creates all sorts of problems, including disrupting thyroid function. In return, your body isn’t able to burn fat effectively and decreases your basal metabolic rate.
If you’re overweight and carry excess body fat, there is a good chance you have some degree of leptin resistance. But it’s also possible to be leptin resistance If you’re underweight and what some call “skinny fat.” If you have or had an eating disorder, you’re likely suffering from a serious leptin issue too.
The easiest test is to look in the mirror. The mirror does not lie and it is really cheap. Step in front of a full length mirror and take a look at your reflection. Do you see a high amount of fat or do you see skinny, but kind of fat (skinny fat)? If you’re either of these, there’s a good chance you might have leptin issues.
But if you want a better way to be sure, measuring your body composition health, especially your visceral fat with a DEXA scan, is another good way. Monitoring specific blood labs like thyroid hormones, vitamin D, and HS-CRP can help identify your leptin status too.
High levels of leptin are associated with:
High levels of white blood cells
Low vitamin D
High levels of visceral fat
Prehypertension
Type 2 Diabetes
Leptin resistance can also lead to liver issues.
What happens when you eat a meal?
When you eat a meal, 60% of calories go to the liver, which in turn routes them to tissues in the body to sustain normal energy production. The other 40% of calories go to peripheral tissue and muscle where insulin allows them to enter the cells.
The remaining 40% of calories is where problems arise if your leptin sensitive or resistance.
If your leptin sensitive, the peripheral tissues and muscles use all of the calories. Meanwhile, if your leptin resistant, the calories that are not used go back to the liver and are stored as fat cells. The more fat that is deposited, the higher leptin levels become. And a buildup of fat in the liver can cause fatty liver or metabolic syndrome.
It can also drive up inflammatory chemicals and things like IL6 (interleukin 6, a pro-inflammatory signal) and TNF alpha (tumor necrosis factor alpha), which increases C-reactive protein and impairs insulin signaling.
This biochemical cascade caused by leptin resistance can lead to preventable diseases like Obesity and Type 2 Diabetes.
Ways to optimize Leptin Sensitivity
If you show signs of leptin resistance, it’s time to start measuring your hormones and other lab markers. There are also a few action steps you can take to regain leptin sensitivity, but we recommend working with a professional to help guide you:
Try reducing your carbohydrate intake and increase protein intake
Don't skip breakfast and avoid eating after dark
Avoid snacking (it can stress the liver)
Optimize your sleep (8 to 9 hours)
Avoid intense exercise until you regain leptin sensitivity
Reduce stress
Signs you’ve become leptin sensitive again include:
Rapid weight loss
Improved mood and sleep
Increased libido
Improved energy levels
Reduced hunger and food cravings
Follow a regimented schedule for at least 6-8 weeks to give yourself the best chance of regaining leptin sensitivity.
That’s it for the first post in our Optimal Labs series. Stay tuned as we get ready to explore your thyroid next!