Understanding Serotonin

Serotonin is a natural neurotransmitter, a chemical that helps relay signals from one area of the nervous system to another. However, there is some debate about its full function. Some researchers consider it a hormone instead. Regardless of how it is classified, researchers agree the body creates serotonin when it processes tryptophan, the foundation of many proteins. When tryptophan reacts with tryptophan hydroxylase in the body, it creates 5-hydroxytryptamine, the scientific name for serotonin.

The brain is the primary origin of serotonin, and the chemical is often found here. However, the brain only accounts for about ten percent of the body's supply of serotonin. The rest exists throughout the digestive and vascular systems, particularly in blood platelets. As of 2019, scientists are still researching the role it plays in these systems.

Serotonin's primary role is to relay signals between various parts of the brain and nervous system, and it appears to play a major role in mood regulation. Basic functions like blood clotting also require this neurotransmitter. Serotonin seems to interact with the digestive system, including triggering nausea and diarrhea if you eat something irritating or toxic.

As mentioned above, serotonin relates to mood regulation. The exact mechanism of this is unclear, but researchers note people suffering from depression tend to have low levels of serotonin. Boosting this chemical can cause a more positive mood and other benefits in many individuals. However, it remains unclear whether low serotonin levels cause depression or whether depression causes the brain to reduce serotonin production.

Research into serotonin's effects on mood and behavior have led to the creation of the SSRI class of drugs -- selective serotonin reuptake inhibitors. These drugs can reduce symptoms of depression and anxiety in many people, and as of 2019 they are the most commonly prescribed antidepressants. SSRIs are generally safe, although their effectiveness varies and they do come with the potential for significant side effects.

Serotonin levels are connected to stress, mood, and general health, so taking care of yourself can go a long way to stimulating natural serotonin production. Exercise and a healthy diet equal healthy serotonin levels, and regular meditation may also help reduce stress and thus boost serotonin. Regular exposure to natural sunlight or products that effectively simulate it, such as some light therapy devices, may also help support healthy serotonin levels.

While serotonin is essential to ensuring the body functions properly, too much serotonin can be detrimental, too. Some studies link high levels to osteoporosis and other bone problems. Excesses can also cause sexual problems, such as low libido or erectile dysfunction. Unusually high natural levels may be a symptom of carcinoid syndrome, which is related to tumors of the colon, appendix, bronchial tubes, and small intestine.

In serious cases, an excess of serotonin can cause serotonin syndrome or serotonin toxicity. This most commonly occurs when a person takes two serotonin-boosting drugs at the same time or overdoses on a single type. Combining SSRIs with MAOIs, another class of antidepressants, or with recreational drugs such as MDMA may also cause the condition. Minor symptoms include headache, nausea, goosebumps and confusion, but they can can escalate into a more severe condition causing muscle twitches, fever, loss of coordination, accelerated heartbeat, seizures, and death.

While serotonin is mostly known for treating depression and anxiety, its role in medicine is much bigger than that. It can be an effective treatment for some types of migraines and insomnia, and is also a common treatment for early-stage symptoms of Parkinson's disease. Some studies also show the neurotransmitter is effective in the treatment of premenstrual syndrome or PMS.

Correcting low serotonin levels often starts with lifestyle improvements, including more exercise and a better diet. In particular, balanced diets rich in salmon, turkey, eggs, cheese, tofu, and nuts are linked to more serotonin production. If you are experiencing more serious symptoms, such as major depression or anxiety, a doctor may be able to recommend medication. People taking SSRIs who experience mild symptoms of high serotonin, such as sexual dysfunction, may require a new prescription. Confusion, muscle twitches, suicidal thoughts, and other serious symptoms should always prompt emergency medical care.