What is Cholecystokinin?


Cholecystokinin, otherwise known as CCK or CCK-PZ, is a hormone that was once called pancreozymin because of its actions on the pancreas. This hormone has receptors through the central nervous system and gut, impacting several areas of the body. Its primary function is on digestion and the appetite, but new research has found other areas where this hormone impacts the body.

Cholecystokinin is a hormone produced in the I-cells that line the duodenum. The hormone is also released by certain neurons in the brain. It seems to be involved in controlling appetite and plays a potential role in anxiety and panic disorders.

How Does cholecystokinin work?

Cholecystokinin's most recognized function is its ability to improve digestion. The hormone reduces the rate at which food empties from the stomach, also stimulating bile production in the liver. Bile shrinks the fat droplets, enabling enzymes to more readily break them down. At the same time, cholecystokinin increases the amount of fluid and enzymes released by the pancreas, so the body better digests food.

In addition, this hormone increases the sensation of short-term fullness, so appetite during a meal is reduced. Some evidence has found that cholecystokinin released in the brain may have an impact on anxiety. However, this particular cholecystokinin function needs further study.

Potential problems with the cholecystokinin hormone

Individuals who have cholecystokinin levels that are too high suffer no known ill effects. In fact, the lack of cholecystokinin side effects sparked research into using it as a weight-loss drug option, because the hormone has an appetite-reducing result.

Too little cholecystokinin can have an adverse outcome on the body. Obese people have been found to have less than the average levels of cholecystokinin, which may contribute to problems with increased appetite and further difficulty with weight loss. In addition, variations with the cholecystokinin gene have been connected to obesity, but the reason for this is not yet known.

Questions for your doctor

If you have questions about your cholecystokinin levels and how they may be impacting your health, it's important to talk to a doctor. While research is still underway to determine what impact cholecystokinin has on obesity and health, your doctor can help you determine if your hormones may be impacting your health. To ensure that the doctor is qualified to discuss hormonal health, you need to work with an endocrinologist. Find an endocrinologist near you today.

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