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Serotonin: The Happy Chemical

Informally known as the happy chemical in our brain, serotonin is a key hormone that helps stabilize our emotions and wellbeing, helping to reduce depression and regulate anxiety. However, it also has an impact on your entire body, as it is involved in eating, sleeping, and even maintaining bone health.

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The Effects of Serotonin on the Body

As previously mentioned, serotonin is a part of many processes within the human body. Below are some of the areas in which serotonin plays a role:

  • Digestion: Controls movements and function in the stomach and intestines; regulates how much fluid is secreted in the intestines

  • Nausea: Production in the bloodstream stimulates the part of the brain that controls the feeling of nausea; promotes the processes of reducing harmful substances

  • Sleep: Induces REM sleep; whether serotonin acts while awake or asleep depends on the area of the brain that is stimulated and which serotonin receptors are used

  • Blood clotting: Released by blood platelets to heal wounds by triggering arteries to narrow, helping to form blood clots

  • Bone health: High levels of serotonin may lead to osteoporosis

Its primary function is to allow for brain cells and nervous system cells to communicate, affecting many cognitive functions such as behaviour, decision making, social behaviour and keeps in check aggressive social responses or impulsive behaviour. Having too much serotonin may lead to high fevers, seizures, and high blood pressure while having low serotonin levels may lead to conditions such as mood and behaviour disorders.

Food's Influence on Serotonin Levels

The brain technically is always functioning, even while sleeping. In order to continue working, it requires a constant supply of fuel, which will come from what you eat. Depending on what types of food the body consumes may have an impact. The gastrointestinal tract is lined with neurons, and its function is influenced by the good bacteria that make up the intestinal microbiome. The bacteria help limit inflammation, improve how you absorb nutrients from your food, and via the vagus nerve have a pathway to the brain, which depending on what you eat may signal certain cravings. A healthy diet is considered to be a natural way of boosting serotonin levels. Levels can change including foods such as eggs, cheese, turkey, nuts, salmon, and pineapple.

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Serotonin's Connections to Mental Health

There have been debates as to whether or not serotonin plays a role in mental health. The connection between vitamin D, omega-3 fatty acids, serotonin levels and mental disorders is a concept explored by many over the years. A study in 2017 looked at data related to vitamin D levels and mental disorders, in which they examined research from PubMed, MedLine literature, and Cochrane databases looking at all publications regarding the issue from 1995- the first quarter of 2017. They found 167 articles are regarding vitamin D and its link or mental disorders.

Newer research claims that an increase or decrease in serotonin may affect depression. In a study conducted in 2014 , Rhona Patrick, and Bruce Ames observed: “Vitamin D regulates the conversion of the essential amino acid tryptophan into serotonin and how this may influence the development of autism, particularly in developing children with poor vitamin D status”.

Later in 2015, Patrick and Ames explored their relevance in terms of other mood disorders such as ADHD (attention deficit hyperactivity disorder), schizophrenia, and impulsive behaviour. One thing that ASD (autism spectrum disorder), ADHD, bipolar disorder, and depression share is low brain serotonin. In their paper, they explain serotonin's role as a “critical modulator of executive function impulse control sensory gating, and prosocial behavior”, meaning it affects how we behave. Once Vitamin D is converted to a steroid hormone, controls roughly 1,000 genes. This further emphasizes the role that serotonin could play in neurogenetic disorders. The publication suggests that these micronutrients could present higher concentrations of serotonin while preventing symptoms of disorders without the side effects

Serotonin as a Treatment

SSRI, or a selective serotonin reuptake inhibitor, is a type of antidepressant which is commonly prescribed since it has fewer side effects than some medications. They are used to treat obsessive-compulsive disorders, panic disorders, hot flashes from menopause, post-traumatic stress disorders, and bulimia. Usually, serotonin circulates in the brain and then is absorbed into the bloodstream.

If serotonin levels are too high or low it's important to speak to a healthcare professional. Make sure to ask if it could be because of certain medication, if you are experiencing feelings of depression, and if it's affecting other aspects of your health.

Serotonin Syndrome

If antidepressants from two different drug potencies are taken, their interaction may lead to getting Serotonin Syndrome which is a fatal condition that can be triggered from too much neuron activity, SS may occur if two or more drugs used to elevate serotonin are taken with the use of different agents. It was discovered in the 1960s regarding studies of monotherapy and combination therapy with antidepressants. There are several drugs in which serotonin may be increased. This includes taking a L-tryptophan supplement, and taking drugs that stimulate serotonin receptors such as lithium, and LSD (lysergic acid diethylamide).


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Featured image is courtesy of Wix.

Article Author: Idil Gure

Article Editor: Maria Giroux, Valerie Shirobokov