What is Leptin?
Leptin is an incredibly important hormone that effects many different functions within the body. It is produced by your adipocytes or fat cells and sends signals to the hypothalamus in the brain when you are satiated from eating. Leptin also has an indirect effect on your metabolism. You see, high levels of leptin cause your thyroid hormones (T3 and T4) to also increase. Upregulation of thyroid hormone increases your metabolism and allows you to burn more calories. Low levels of leptin causes thyroid to drop, and slow down your metabolism.
Dieters that have had early success with a weight loss protocol and then hit a plateau have felt the negative effects of low leptin levels. This is because when you have lots of fat your fat cells produce a lot of leptin, but once you start losing body fat, leptin levels wane and so does your fat loss progress. This is one of the reasons why fat loss can be so difficult: the less you eat, the lower your leptin levels are, the lower your leptin levels the more your metabolism slows, and when leptin drops the hungrier you get. How can you win?!
Its almost as if humans were designed to be fat! Why is this? Well, leptin has been referred to as the “anti-starvation” hormone and for good reason. Your body has evolved to slow down your metabolism for survival when food sources are scarce. Fortunately and also unfortunately, today, we live in a world with an abundance of food. When we want to cut back on calories our body starts to go into survival mode and slows your metabolism down to a halt. When humans were hunter gathers that went days before their next big meal this helped us survive. Now it helps to make us programmed to put on fat.
Here are some good tips and tricks that will help you be well on your way to hacking your leptin levels even when dieting:
- Get more vitamin D via supplementation or the old fashion way- direct sunlight. Vitamin D helps you release more leptin which will help prevent you from overeating.
- Don’t go too far into a caloric deficit. No more than 500 calories at the most. For example, if you normally eat 2500 calories a day and want to go on a diet; don’t drop your daily caloric intake below 2000 calories.
- Avoid fructose. Fruits contain a lot of fructose and excess consumption of them can be detrimental to your fat loss. A study performed on mice found fructose intake causes leptin resistance which subsequently led to weight gain in the mice.
- Last but not least my favorite tip: Get in a cheat meal every once in awhile- Maximum once per week.
- Try getting some cold exposure with a daily cold shower
- Get adequate amount of sleep
- Lift weights
There is another phenomenon that also has an effect on body composition which is called leptin resistance. Just like insulin resistance, when you are resistant to the hormone leptin, your brain requires more leptin to make you feel full. The problem with this is if your brain isn’t responding to the leptin your body is producing then you will over eat and gain fat.
Another negative of chronically high leptin is it makes you extremely sensitive to the “hunger hormone” ghrelin. Therefore, it only takes a small amount of ghrelin to make you feel hungry which then makes you eat more and raise leptin levels even higher! It can become a pretty vicious cycle.