What is Ghrelin?


Ghrelin is central to appetite and the release of growth hormone. To stay as healthy as possible, take the time to understand this important hormone and its impact on the body.

Ghrelin is produced in the stomach and small intestine, with a little bit of the hormone released in the pancreas and brain. It has been called the "hunger hormone" because of its role in controlling appetite, but that is just one of its functions.

How does ghrelin do?

Ghrelin serves many purposes, but the one most commonly talked about is its ability to stimulate appetite, causing an individual to digest more food and store more fat. In fact, when given artificially to humans, the amount of food intake increases by 30%. The hormone plays a role in the hypothalamus, the part of the brain that controls appetite, and also may act on regions of the brain that control reward processing.

Ghrelin also plays a role in the pituitary gland’s function, where ghrelin receptors trigger the stimulation of the hormone. It appears to help control insulin release, and plays a protective role in cardiovascular health. This well-rounded hormone has a job in many different bodily systems.

Problems associated with ghrelin

Because ghrelin affects appetite, it can impact weight loss, especially when someone diets. When someone is strictly controlling calories, ghrelin levels increase. This, then, causes the rebound of the pounds lost that happens right after a diet for many people. People who struggle with anorexia nervosa may also have high ghrelin levels, which occurs as part of the body's natural response to starvation.

For patients with Prader-Willi syndrome, ghrelin levels in the blood are high. This is believed to be the reason why these patients struggle with severe obesity and extreme hunger. The ghrelin levels increase before obesity, so it is not caused by the higher body weight.

On the other hand, patients who have gastric bypass surgery can have lower ghrelin levels than those who lose weight naturally. This may be why gastric bypass surgery, if the eating plan is followed strictly, has long-term effectiveness regarding weight loss.

Questions to ask your doctor

If you are trying to control your hunger and weight, understanding ghrelin function may help. Consider asking your doctor:

  • How can I naturally control ghrelin?
  • Are ghrelin blocker products an effective way to control hunger?
  • Are my ghrelin levels responsible for my weight struggle?
  • How can I lose weight without impacting ghrelin levels negatively?
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The Hormone Health Network is the public education affiliate of the Endocrine Society dedicated to helping both patients and doctors find information on the prevention, treatment and cure of hormone-related conditions.

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