It’s no secret that some people naturally have a harder time than others when it comes to losing weight. One reason may be because leptin levels in the body are skewed. Leptin plays a powerful role in regulating appetite and metabolism, which is why knowing how it works is so important.
Leptin is a “master hormone” that is sometimes referred to as the “starvation hormone.” Manufactured in white andipose tissue (stored fat), it binds to receptors in the brain that control the appetite. Its second function is to increase sympathetic nervous system activity, which then causes fatty tissue to be burned as energy. Each individual has preset leptin hormone levels that vary from person to person.
When people diet, they eat less, causing the fat cells to shed fat. This in turn decreases the amount of leptin produced by the body. Once leptin levels dip below a person’s threshold, the body then goes into “starvation mode” and begins conserving energy. The hormone will also trigger hunger to encourage eating, sending signals once the brain senses the stomach is full. This signal then causes the metabolic rate to increase. Remaining in a calorie deficit too long will eventually slow one’s metabolism and make burning calories more difficult.
Leptin resistance occurs whenever large amounts of leptin are present in the body, yet the hormone has little or no effect on the brain. It is a concept similar to insulin resistance, and is often caused by too much sugar (especially fructose) in the diet. If you are leptin resistant, your body cannot discern that your fat levels are too high. In other words, there is a lot of leptin circulating in your blood, but it does not affect your appetite or energy.
Dr. Robert Lustig, MD, a professor of pediatrics at the University of California in San Francisco, claims there is no need to give leptin supplements to those who are leptin resistant. According to Dr. Lustig, no amount of supplemental leptin will overcome a person’s resistance to it. Other doctors claim that leptin supplements typically work only in individuals who do not produce their own leptin, a condition that is extremely rare.
The best thing you can do to maintain the proper leptin levels is to stay at or near your targeted weight. When dieting, perform a refeed or allow yourself to have a “cheat day” whenever you notice your metabolism slowing. Eat only the recommended level of carbs, as a spike in carbohydrates can increase insulin levels and cause leptin production to spike. You should also get plenty of sleep, as studies show those who are sleep deprived have 15% less leptin in their bodies than others.
Leptin is a powerful hormone that can either work for you or against you to help you lose weight. As such, it is very important to do everything you can to ensure your leptin hormones levels remain where they are supposed to be.