What does serotonin do in the body?

Serotonin is commonly referred to as the happiness hormone - but this is only partly true. Because apart from the fact that it acts in the brain as a messenger substance and not as a hormone, there are numerous other functions that serotonin performs in the body besides its mood-positive effect.

How does serotonin work in the body?

Serotonin (also: 5-hydroxytryptamine, or 5-HT for short) belongs to the neurotransmitters. These are messenger substances whose task is to transmit information between nerve cells. To transmit information, neurotransmitters such as serotonin need receptors in the body to which they dock. Serotonin can dock to at least 14 different receptors, and depending on which 5-HT receptor type it is, receptor binding results in a different reaction in the body. This means that the serotonin effect depends on which receptor the neurotransmitter binds to.

Where does serotonin act in the body?

Basically, serotonin shows its effect in the peripheral and central nervous system, in the blood as well as in the gastrointestinal tract and is involved in different body functions in each case.

In the central nervous system, the most important functions in which serotonin exerts its effect include the regulation of appetite, body temperature, moods, emotions and drive. Serotonin is best known for its effect on mood. However, the serotonin effect does not manifest itself in a euphoric mood, but rather produces a sense of well-being, balance and contentment. Therefore, because of this effect, serotonin is often popularly referred to as the happiness hormone or feel-good hormone.

However, it also has other effects in the brain. Among other things, it influences the perception of pain, the sleep-wake rhythm and the reward system. Serotonin is also said to influence memory performance. Because of these numerous influences, a disturbed serotonin balance is associated with various disorders related to emotional processes, such as anxiety disorders, obsessive-compulsive disorders, and depression.

What else does serotonin do in the body?

Outside of the brain, serotonin also has various effects in the body: Almost all of the serotonin (95%) found in the blood is found in the blood platelets (thrombocytes). There it fulfills an important task: it increases the activity of the blood platelets (thrombocytes) when a blood vessel is injured, so that they can close the injury again more quickly.

In the gastrointestinal tract, serotonin has a stimulating effect on the intestines, i.e. it influences intestinal movements (peristalsis) and thus also regulates bowel movements. In gastrointestinal problems, serotonin production increases, controlling diarrhea and nausea, among other things.

Serotonin also seems to play a role in bone health, as a permanently too high level of serotonin in the body can result in diseases such as osteoporosis.

Conclusion on serotonin in the body

The neurotransmitter serotonin is essential for health and well-being because it performs numerous important functions in the body. Serotonin's effects are primarily seen in the brain, blood and gastrointestinal tract, where it can bind to various receptors and thus trigger different processes in the body.