“What the heck is leptin?”- you rightfully ask your self. Hang on and I’ll do my best to explain.
Leptin is a small protein – a hormone – that is secreted from your adipose tissue, your fat cells. I bet you never heard about it before. Most haven’t, not even medical doctors. And if they know about it they probably haven’t paid much attention to it.
For many years the adipose tissue was believed to be there just for storage purposes. During the last decade research has started to change this idea. The adipose tissue is participating and seems to be controlling many functions in the body, such as hunger, energy balance, calcium balance, inflammation and might also play a part in hormonal signalling over all.
The main purpose of leptin is to signal to the brain about starvation. The more fat you have in your stores, the higher the leptin signal. When the levels rise the hormone acts on a part of the brain called the arcuate nucleus, located just right between your eyes, 5 inches back. These nerve cells control your feelings of hunger and satiation. The more leptin the less hungry you’ll be. Every time you eat and start storing energy (especially glucose) into the fat cells there will be a leptin surge, signalling to your brain that energy levels are good.
It seems to be that a chronically elevated leptin might lead to leptin resistance, that is your brain is no longer responding to the signals your fat cells are sending out. Since different parts of the brain has different sensitivity for leptin some parts will be deaf for the screaming of the hormone while other parts will keep answering to the higher levels. There is evidence pointing towards leptin resistance being the precursor to insulin resistance, but also a suggestion that elevated insulin levels might disrupt the signalling from leptin. What came first, the chicken or the egg? Hard to tell.
In the upcoming posts we will uncover some of the secrets of leptin and how leptin resistance might develop, how you can get out of it and what impacts high leptin levels and how leptin resistance might affect your body.