Hormones have a deep impact on the health of those suffering from obesity &/or overweight. Having excess body fat can lead to Hormonal issues. Leptin is one of the Hormone directly linked with weight & obesity.
Leptin, a hormone directly released from fat cells & located in adipose tissue, sends signals to hypothalamus in the brain. This hormone regulates long term food intake & energy expenditure. It helps to maintain body weight. Since Leptin comes from fat cells, it is directly related to the amount of body fat. If a person increases the body fat percentage, the Leptin level would be increased & vice versa.
Leptin is also called Satiety Hormone. It inhibits hunger & regulates energy balance so that body does not get signals hunger responses when it does not need energy. However, when the Leptin level goes down which generally happens when a person loses weight. Such low level of Leptin can trigger increase in food cravings & makes weight loss much more difficult.
When the body is functioning properly, excess fat cells will produce Leptin which will signal hypothalamus to reduce the appetite. Hence the body will resort to fat stores to generate energy. However, there is a flip side when someone is obese. Obesity causes a high level of Leptin in the blood. This can reduce the sensitivity to hormone & is referred to as Leptin resistance. Since the person keeps eating, the fat cells produce more leptin to signal the feeling satiety, leading to increased Leptin level.
Low levels of Leptin are rare but can occasionally occur. For some folks, disease known as congenital Leptin deficiency keeps the body from producing Leptin. With literally no leptin,
- The body thinks there is no fat & signals a huge need for hunger & uncontrolled food intake. This results in severe childhood obesity. This can be cured by taking Leptin injections.
- It also reduces energy expenditure: In order to conserve energy, your brain decreases your energy levels & makes you burn fewer calories at rest.
Thus, eating more and exercising less is not the result of weight gain but rather a possible consequence of leptin resistance, a hormonal defect.
Leptin resistance is one of the reasons that many diets fail to help achieve our weight loss objective. If you are Leptin resistant, you do lose weight but it also leads to mass/muscle loss which eventually reduced your Leptin levels. However your body does not reverse Leptin resistance.
When Leptin level goes down, it increases hunger & appetite, reduces motivation for hunger & reduces the calories burnt at rest. Your brain thinks that you are starving & initiatives all active that makes you regain your lost fat. This is the reason why so many people regain fat even after body/health transformation.
What causes Leptin Resistance?
The following are culprits behind Leptin Resistance:
- Inflammation: Inflammation signalling in your hypothalamus is an important cause of Leptin Resistance.
- Elevated Free Fatty Acids: Having elevated free fatty acids in your bloodstream shall increase fat metabolites in your brain, interfering with Leptin signalling.
Both of these factors are amplified by obesity which creates a vicious circle of increasing weight & becoming Leptin Resistance.
