Many people believe that weight gain and weight loss is all about calories and willpower. Me included.
Leptin controls your metabolism, hunger, and energy expenditure. A leptin system that is working properly improves brain fitness, mental sharpness, leads to better memory, and enhances mood.
It is supposed to tell the brain that we have enough fat stored, that we don’t need to eat, and that we can burn calories at a normal rate. This hormone is produced by the body’s fat cells. The more body fat they carry, the more leptin they produce. It is carried by the bloodstream and into the brain, where it sends a signal to the hypothalamus, the brain area that controls when and how much we eat. The fat cells use leptin to “tell” the brain how much body fat they carry. Lots of leptin tells the brain that we have plenty of fat stored, while low levels of leptin tell the brain that fat stores are low and that we are at risk of starvation.
Leptin is also directly tied to insulin levels. Your blood sugar regulator.
Leptin Resistance – weight gain
Being overweight causes a lot of body fat in the fat cells.
Because fat cells produce leptin in proportion to your size, causes very high levels of leptin. The way leptin is supposed to work, your brain should know that you have plenty of energy stored. The problem is that the leptin signal isn’t working. There’s a whole ton of leptin floating around, but the brain doesn’t “see” that it is there. Leptin resistance.
When the brain doesn’t receive the leptin signal, it erroneously thinks that the body is starving, even though it has more than enough energy stored.
- Eating More: The brain thinks that we MUST eat so that we don’t starve to death.
- Reduced Energy Expenditure: The brain thinks we need to conserve energy,
Trying to exert willpower over the leptin-driven starvation signal is next to impossible
People who are obese have high levels of leptin, but the leptin signal isn’t working due to a condition known as leptin resistance. Leptin resistance can cause hunger and reduced energy expenditure. Losing weight reduces fat mass, which leads to a significant reduction in leptin levels, but the brain doesn’t necessarily reverse its leptin resistance. When leptin goes down, this leads to hunger, increased appetite, reduced motivation to exercise and decreased amount of calories burned at rest. When people lose fat, leptin levels decrease significantly. The brain interprets this as a starvation.
Next blog - how to get your Leptin working for you.