This Hormone Might Be The Reason You Can't Lose Weight

Leptin, which was formally discovered in 1994, is a protein manufactured within fat cells that circulates through the blood stream and signals to the hypothalamus — the part of the brain controlling body temperature, thirst, hunger, and emotional activity — whether your fat cells have enough energy to fuel the body's normal metabolic processes. Because of its role in regulating hunger, leptin was thought to be a potential tool to help weight loss — but Robert H. Lustig, MD, professor of pediatrics at the University of California, argues that, instead, leptin is really a potential cause of weight gain.

When leptin levels are above a certain threshold, the brain is given the signal to stop eating, and the body burns energy at a healthy rate; if leptin levels are unbalanced, though, this seemingly harmless hormone can adversely affect your ability to shed pounds. Lustig warns that if not enough leptin reaches the brain; it signals to the body that it's still hungry, or worse, starving. As the brain enters starvation mode, a number of processes go into motion — all of which stymie weight loss: You get hungrier, you take in extra energy, and you store fat in order to re-establish "normal" leptin levels.

But it's not a lack of leptin that's necessarily problem — this could be easily be remedied with supplements — rather what leads to weight gain is leptin resistance, a condition that prevents the brain from receiving the signal to stop eating. Without this natural indictor, the body becomes obese, but the brain believes it's starving. Living with leptin resistance makes weight loss a struggle, but there are ways to naturally reestablish leptin sensitivity. Lustig recommends bringing down triglyceride levels by limiting saturated fat intake, eating more omega-3 fatty acids, and engaging in weekly exercise. High triglyceride levels seem to block leptin transport into the brain, and in order to make your leptin work, you have to let the signaling occur. "The only way to let the signaling occur it to get your triglyceride down," notes Lustig.