Ghrelin is a hormone. Its primary role is to regulate appetite. It also facilitates the function of the pituitary gland, controls insulin, and protects cardiovascular health.

In this article, we explore what ghrelin is, its functions and other effects, and how a person can reduce the amount in their body.

a woman eating a vegan meal because she is high in ghrelin levelsShare on Pinterest
Ghrelin regulates appetite.

Ghrelin, also known as the “hunger hormone,” is a circulatory hormone that has many functions in the body.

The production and release of ghrelin occur mainly in the stomach but also in the small intestine, brain, and pancreas.

Although ghrelin performs various roles in the human body, its main functions revolve around the gastrointestinal area. This part of the body includes the stomach and small intestine.

Ghrelin facilitates the sensations of hunger and fullness, and it promotes fat storage.

Levels of ghrelin change significantly throughout the day, increasing when a person is hungry and decreasing after eating.

As well as dictating hunger and satiety, ghrelin has several other functions. Some of these include:

  • Pituitary gland secretion: The pituitary gland is in the brain, and its main function is to release hormones. It consists of two major parts: the anterior lobe and the posterior lobe. Ghrelin helps the pituitary gland secrete anterior pituitary hormones.
  • Insulin regulation: Some evidence suggests that ghrelin may aid in regulating insulin. It does this by controlling insulin secretions and the signaling of insulin receptors.
  • Cardiovascular health: Ghrelin can have several beneficial effects on the heart and may be a promising therapeutic agent in treating cardiovascular disease. However, the underlying mechanisms behind how ghrelin benefits the cardiovascular system are not fully clear.
  • Reward-based behavior: Ghrelin may act as a signal that stimulates a reward pathway between the stomach and brain. Therefore, it may play a part in hedonic eating, where people consume food for pleasure as opposed to necessity.
  • Sexual behavior: A study examining mice found that when male mice receive a supplement of ghrelin, this leads to an increase in their sexual behavior. More research is necessary to assess whether the same is true in humans.

A person needs ghrelin in their body to maintain and regulate some vital bodily functions. However, as ghrelin plays a key role in hunger and satiety, reducing levels of ghrelin may cause people to have less appetite and, as a result, lose weight.

Some research shows that ghrelin levels increase after weight loss. A person may feel hungrier than usual, leading them to eat more and possibly put on the weight that they lost.

However, research highlights that changes in ghrelin levels alone are not a sufficient predictor of weight gain after weight loss. Behavioral and environmental factors may also play a part.

A person who wishes to reduce ghrelin levels in their body naturally can try the following:

Reduce intake of fructose

Studies highlight that consuming foods high in fructose may increase ghrelin. The raised levels of this hormone may make a person eat more during a meal or feel hungry soon after a meal.

Eat more of certain nutrients

Consuming meals high in protein may suppress ghrelin, leading to more sustained feelings of fullness.

One study suggests that men with an average body weight felt fuller and had lower ghrelin levels after consuming high carbohydrate meals. These results were not apparent in the participants with obesity.


There is some debate as to whether exercise can increase or decrease levels of ghrelin in the body. A 2018 review found that intense aerobic exercise may reduce levels of ghrelin, while another found that circuit exercises may increase ghrelin levels.

Even though some forms of exercise may increase ghrelin levels, this might not affect the feeling of hunger. Exercise also affects other hormones, such as insulin and leptin, which also play a role in hunger.

Reduce stress

High and chronic levels of stress may cause ghrelin levels to rise. Due to this, people experiencing these types of stress may overeat. If people feel comforted by eating during periods of stress, this may activate the reward pathway, and they may lean toward comfort eating.

Limit cannabis

There is also some evidence that cannabis stimulates the release of ghrelin. Experts believe that tetrahydrocannabinol (THC), the psychoactive compound in cannabis, is primarily responsible.

A 2020 study found that taking cannabis orally led to higher ghrelin levels than smoking or vaporizing it. This route of administration may, therefore, cause a person to feel hungry and eat more food.

Ghrelin is a hormone that has many functions in the human body. These include regulating the appetite, controlling insulin, and improving cardiovascular health.

A person requires ghrelin to regulate various bodily processes. However, some people may wish to reduce the amount in their body because doing this may suppress the appetite, resulting in a person eating less.

Those who wish to reduce ghrelin levels in their body naturally may consider reducing their intake of fructose, exercising, and attempting to minimize their stress levels.