Serotonin deficiency has been linked to both physical and mental symptoms. How does such a shortage arise? And more importantly, how do you increase serotonin naturally? You can read it in this blog.

What is Serotonin?

Serotonin, or 5-hydroxytryptamine (5-HT), is a neurotransmitter. This is a signaling substance of the nervous system. About 95 percent of serotonin is produced in your gut and only five percent in your brain.[1]

Serotonin is best known for the role it plays in your mood and behavior. It is also known as a ‘happiness substance’. In addition, serotonin also plays a role in your sleep, appetite, digestion – intestinal peristalsis, absorption and storage of nutrients -, immune system, bones, cardiovascular function, breathing, bladder function, blood sugar regulation, liver function and metabolic homeostasis.[2], [3] , [4]

In a serotonin deficiency, serotonin does not work as it should. It may be that your body does not make enough serotonin or that your body does not use the serotonin efficiently.

What are the symptoms and consequences of a serotonin deficiency?

Serotonin deficiency has been associated with both physical and psychological complaints, but the exact role of serotonin in this is not yet fully understood.

Physical and mental complaints associated with a lack of serotonin:

• Decreased peristalsis of the intestines (constipation, goat droppings)

• Bowel problems: irritable bowel syndrome, Crohn’s and ulcerative colitis[5], [6]

• Increased pain sensitivity, chronic pain (fibromyalgia)

• Dementia, memory problems[7]

• Craving for sugar

• Obesity, diabetes and cardiovascular disease[8]

• Osteoporosis (bone loss)[9]

• Sleep problems and fatigue[10]

• Mood problems, sad mood, feeling sad[11]

• Obsessive Compulsive Disorder (OCD), Panic Disorder, Suicidal Thoughts, Post Traumatic Stress Disorder (PTSD) and Social Anxiety Disorder[12]

• Aggression and irritability[13]

• Anxiety, restlessness[14]

• Impulsive behavior[15]

How does a serotonin deficiency develop?

An important cause of a deficiency of serotonin is inflammation. This ensures that the building material of serotonin – the amino acid tryptophan – is broken down more quickly via the so-called kynurenine route, so that insufficient tryptophan remains for the production of serotonin. A shortage of tryptophan can also be caused by a shortage of intake in your diet.[16]

In addition, a serotonin deficiency can also be caused by nutritional deficiencies, such as a deficiency of vitamin D and omega-3 fatty acids.[17] But also a deficiency of iron, vitamin B6 and folic acid. These substances are necessary for the production and functioning of serotonin.

Furthermore, based on animal studies, some researchers suspected that early life stress and a disturbed gut flora can cause a serotonin deficiency.[18], [19]

How do you diagnose a serotonin deficiency?

Serotonin deficiency is generally not diagnosed by doctors because no diagnostic criteria have been established for it. There are no good tests to diagnose a lack of serotonin. That is why the symptoms are often looked at to gain insight into whether there may be a problem with serotonin.[20] To get an idea of ​​the amount of serotonin in the brain, according to some researchers, you could look at the amount of tryptophan in the plasma.[21]

Ways to Increase Your Serotonin

Below you will find a number of ways to increase your serotonin and/or make it work better. Keep in mind that the supplements mentioned below can interact with medication and as a result, in some cases, may have unwanted effects. Therefore, always consult an integrative medicine therapist if you want to use supplements.

Solve inflammation

Inflammation ensures that the building material of serotonin (tryptophan) is broken down more quickly. Any inflammation that is present must therefore be resolved. Indications of inflammation include redness, pain, itching, fatigue for no apparent reason, and elevated blood levels of inflammation such as CRP, BSE, and uric acid. Inflammation can have many causes. An integrative medicine therapist is trained in detecting the causes and can help you with this.


Aerobic exercise increases your serotonin.[22] Examples include walking, cycling, swimming and gardening.

Body contact

With pleasant body contact – such as during a massage – you produce serotonin.[23] Therefore, make sure you have regular body contact in the form of sex, hugs and massages.

Fill nutritional deficiencies

Tryptophan, omega-3 fatty acids, vitamin D, iron, vitamin B6 and folic acid are needed for the production of serotonin.[24], [25] Make sure you get enough of this and use supplements if necessary to make up for deficiencies.

Griffonia simplicifolia (5-HTP)

Griffonia simplicifolia contains 5-hydroxytryptophan (5-HTP). You can make serotonin from this. You can buy Griffonia simplicifolia in the form of a supplement. 5-HTP can cross the blood-brain barrier, after which it can be converted into serotonin. The advantage of Griffonia is that the 5-HTP is also converted into serotonin during inflammation. This is in contrast to ‘normal’ tryptophan, which is rapidly broken down during inflammation via the kynurenine pathway. It is therefore better to opt for a Griffonia supplement than a tryptophan supplement.

Saffron and St. John’s Wort

Supplements with extracts of saffron (Crocus sativus) and St. John’s wort (hypericum perforatum) can increase your serotonin and make it work better.[26], [27]

Myths About Serotonin

There are a number of misunderstandings about serotonin that we would like to clear up. Because serotonin is mainly produced in the gut, many people think that this serotonin also works in your brain. But this is not the case, because serotonin cannot cross your blood-brain barrier. Serotonin that is produced in your gut can therefore not end up in your brain and can therefore not be effective there. The serotonin in your brain is produced on the spot from tryptophan – or 5-HTP. Tryptophan and 5-HTP can cross your blood-brain barrier. This also means that serotonin from foods, such as bananas, pineapple, kiwis, plums, tomatoes and walnuts [28], [29] cannot reach your brain and can therefore not be effective there.

Furthermore, tryptophan from food generally does not increase serotonin in your brain, but a supplement with pure tryptophan that is taken on an empty stomach – provided there is no inflammation. This is because the absorption of tryptophan in your brain is hindered by the other amino acids in your diet.[30] This is also why tryptophan supplements should always be taken on an empty stomach. On the other hand, a lack of tryptophan in your diet does cause a decrease in serotonin in your brain.


1 Banskota, S., Ghia, J. E., & Khan, W. I. (2019). Serotonin in the gut: Blessing or a curse. Biochimie161, 56-64.


[3] Banskota, S., Ghia, J. E., & Khan, W. I. (2019). Serotonin in the gut: Blessing or a curse. Biochimie161, 56-64.

[4] Yabut, J. M., Crane, J. D., Green, A. E., Keating, D. J., Khan, W. I., & Steinberg, G. R. (2019). Emerging roles for serotonin in regulating metabolism: New implications for an ancient molecule. Endocrine reviews40(4), 1092-1107.

[5] Banskota, S., Ghia, J. E., & Khan, W. I. (2019). Serotonin in the gut: Blessing or a curse. Biochimie161, 56-64.








[13] Sascha Russo, J.G. Boon & Jakob Korf (2006). Serotonine anders bekeken. Huisarts en Wetenschap.



[16] Sascha Russo, J.G. Boon & Jakob Korf (2006). Serotonine anders bekeken. Huisarts en Wetenschap.

[17] Patrick, R. P., & Ames, B. N. (2015). Vitamin D and the omega‐3 fatty acids control serotonin synthesis and action, part 2: Relevance for ADHD, bipolar disorder, schizophrenia, and impulsive behavior. The FASEB Journal29(6), 2207-2222.

[18] El Aidy, S., Ramsteijn, A. S., Dini-Andreote, F., van Eijk, R., Houwing, D. J., Salles, J. F., & Olivier, J. D. (2017). Serotonin transporter genotype modulates the gut microbiota composition in young rats, an effect augmented by early life stress. Frontiers in cellular neuroscience11, 222.

[19] Yano, J. M., Yu, K., Donaldson, G. P., Shastri, G. G., Ann, P., Ma, L., … & Hsiao, E. Y. (2015). Indigenous bacteria from the gut microbiota regulate host serotonin biosynthesis. Cell161(2), 264-276.


[21] Sascha Russo, J.G. Boon & Jakob Korf (2006). Serotonine anders bekeken. Huisarts en Wetenschap.