Leptin is a hormone produced by fat cells in the body. It is the gatekeeper of fat metabolism, monitoring how much energy a person takes in. Leptin acts to maintain energy balance in the body by regulating metabolism and hunger. The level of leptin circulating in your body is directly proportional to the total amount of fat you have. That means the more fat you have, the greater the amount of leptin you have. When present in high levels, it signals our brain that we’re full and can stop eating. When low, we feel hungry and crave food.

Most people don't have a leptin deficiency, rather they have lost sensitivity to their leptin. Much like insulin resistance, it's possible to have enough leptin in your blood, but because your body doesn't use it effectively, you still feel hungry. In these cases, the leptin is not getting into the brain effectively and it is important to take measures to improve your body’s leptin sensitivity. This improvement can help you maintain a stable body weight.

Instructions

Fasting is not required. Take all medications as prescribed.

Note

It is generally best to also measure C-reactive protein (CRP) if you are testing leptin, since high levels of CRP can bind leptin and prevent it from getting into the brain effectively.