4 Ways the Endocrine System Interacts With Body Weight

The human body is made up of a complex set of interconnected systems. Hormones are one of the primary ways that these systems communicate with one another. The human body produces over 50 different types of hormones that perform a diverse array of functions, including controlling blood sugar levels, signaling appetite, and regulating metabolism. Because of these and other functions, personalized weight loss programs often include diagnosis and treatment by an endocrinologist of any underlying hormone imbalances. In this respect, it is fair to describe many endocrinologists as weight loss doctors.

Here are four links between the endocrine system and weight gain that a weight loss doctor may utilize during a personalized weight loss program:


Leptin is a hormone that is produced by fat cells in adipose tissue. Adipose tissue is the connective tissue that we associated with “fat.” Adipose tissue serves some important functions, such as insulation, cushioning the body and organs, and storing energy. However, too much adipose tissue relative to your body structure is defined as obesity. In other words, obesity is not about weight; a person can be “heavy” for her height simply because she is muscular. Rather, obesity is about excess adipose tissue for a body structure.

Leptin relates to obesity in three ways.

  1. Since fat cells produce leptin, leptin is sensed by the body as “satiety” or the opposite of hunger. This makes sense, since the more fat cells adipose tissues have, the more leptin is produced and the less fuel the body needs to take in. Therefore, more fat cells should reduce appetite.
  2. However, this is not what happens. As a body increases its stores of fat cells, the brain begins to “ignore” leptin. More particularly, the body becomes accustomed to higher leptin levels and stops interpreting the hormone as signaling satiety. As a result of this leptin resistance, the obese body feels hungry all the time.
  3. Leptin is also responsible for the failure of dieting. Reducing food intake causes leptin levels to fall. Since the body becomes accustomed to high leptin levels, this fall is interpreted by the body as starvation, causing you to overeat.

Because of its role in hunger and satiety, leptin is of high interest to weight loss doctors.


Insulin is produced by the pancreas in response to blood sugar levels. When blood sugar levels are high, the pancreas signals the liver and muscles to remove glucose from the blood. Glucose removed by the liver is stored in the liver or used to build fat cells.

When the intake of sugar is consistently high, this causes the pancreas to secrete high levels of insulin. As with leptin, the body grows accustomed to these high levels of insulin, a condition known as insulin resistance. Eventually, the pancreas burns out from the overproduction of insulin and its ability to produce insulin is diminished or lost. This condition is known as type II diabetes.

Weight loss doctors are very wary of insulin and blood sugar levels since they can lead to this life-threatening condition.

Testosterone and Estrogen

You may have noticed that women and men are typically built differently. The hormone that tells female bodies to build fat cells and place them around their hips, buttocks, and thighs is estrogen.

In male bodies, testosterone plays a more complicated role. Testosterone promotes belly fat and muscle building. When testosterone levels are too high or too low, the body can be more prone to developing belly fat. This is the reason that men are prone to developing a potbelly as they age and testosterone levels drop.

An imbalance in estrogen or testosterone can cause fat accumulation and, as such, is an issue that can be addressed by a weight loss doctor when customizing a weight loss plan.

Growth Hormone

Growth hormone is produced by the pituitary gland. It is responsible for signaling the body to grow bone and muscle tissue. Growth hormone also helps the body regulate metabolism.

The reasons that human growth hormone is susceptible to abuse by athletes are the same reasons an imbalance can affect weight gain. In particular, growth hormone:

  • Stimulates muscles to take in protein
  • Enhances the use of fat to supply the body with energy

There are many more links between the endocrine system and weight gain. Understanding these links can help you lose weight. For more information, don’t hesitate to reach out to Dr. Philip Rabito. 

Philip Rabito, MD

Contact Us Today

*All indicated fields must be completed.
Please include non-medical questions and correspondence only.

Located just steps away from the 77th street subway stop on the 6 line

Accessibility Toolbar