Leptin is the chief body fat setpoint regulating hormone. It acts on the hypothalamus region of the brain to control our metabolism, nutrient uptake from food, hunger and satiety signals.
Here is how your normal body regulates fat mass and caloric intake
In normal functioning humans, leptin increases as you begin to overeat, and as fat begins to accumulate. The rise in leptin signals the hypothalamus that enough nutrients have been taken in. The increase in leptin tells your body to slow down the hunger signals, speed up the metabolism, and reduce the absorbtion of nutrients.
Likewise, as you fast or fat mass decreases, leptin also decreases. The hypothalamus notices a lack of leptin, and signals the body to slow down metabolism, increase nutrient uptake, and increase hunger.
Here is how a malfunctioning body regulates fat mass and caloric intake
In poorly functioning humans, such as the obese, the leptin signal is muted, and the hypothalamus has difficulty “hearing” the signal. This causes the body to continue to uptake nutrients, slow metabolism, and increase hunger, until the leptin signal is amplified by a greater fat mass, to the point that the hypothalamus is finally able to “hear” the signal. This is how the malfunctioning body defends an incorrect higher-fat mass.
This is called leptin resistance, or a lack of leptin sensitivity.
What causes leptin resistance at the hypothalamus? Inflammation!
Lowering systemic inflammation in the body, by eating a functional Paleo diet and removing neolithic food toxins, as well as staying away from hyper-palatable high hedonic reward foods, is the best way to “deflame” your body, and bring leptin sensitivity back within a healthy range.
Once you have eliminated inflammation and your hypothalamus is able to accurately read leptin signals, your body will self-regulate to a lower body fat setpoint, making fat loss and body recomposition easier.