Serotonin - Effects, Function & Importance for our Body

Want to boost your mood at the push of a button? The neurotransmitter serotonin makes it possible. Learn everything you need to know about the effects, function, and importance of serotonin here.

What is serotonin?

Serotonin is a molecule found in humans and almost all other animals, as well as plants. It acts as a hormone, neurotransmitter, and messenger substance in our bodies. The chemical name for serotonin is 5-hydroxytryptamine (5-HT).

It was formerly also called enteramine, but at that time it wasn't known that serotonin and enteramine are the same substance. It wasn't until 1952 that it was proven that they are the same molecule. Scientists discovered early on that serotonin is found in various tissues. For example, it is present in the brain, lungs, kidneys, blood platelets, and the gastrointestinal tract. You can either absorb serotonin directly or the body can synthesize it from its building blocks. However, the neurotransmitter cannot cross the blood-brain barrier, so the body's own production plays a crucial role in brain function.

This is how serotonin production works

The hormone is primarily produced in the intestinal mucosa. Since it cannot cross the blood-brain barrier, production in the central nervous system is also possible. The precursor for serotonin production is tryptophan. This is an essential amino acid, meaning it's a building block of proteins that the body cannot produce itself. This immediately clarifies the connection between serotonin and nutrition, because without sufficient tryptophan intake, serotonin cannot be produced. Tryptophan is converted into the neurotransmitter in two steps. In the first step, tryptophan is hydroxylated to 5-hydroxytryptophan (5-HTP) through the activation of vitamin D.

You might be familiar with 5-HTP, as it's sold as a dietary supplement for rapid serotonin production and restful sleep. The second step involves decarboxylation, which requires vitamin B6 as a cofactor. If all of this sounds a bit too technical, don't worry. The key takeaway is simple: sufficient tryptophan must be consumed for serotonin production. Tryptophan is a component of your diet and is found in several foods.

What does serotonin do in the body?

Since serotonin is found in many different tissues, it's reasonable to assume that it performs various functions in the body. And that's indeed the case. Its function in the central nervous system is quite different from that in the rest of the body (the periphery), which is why it makes sense to divide it into these two areas. There are at least 15 different receptors to which serotonin can bind. This allows the body to react to different serotonin concentrations and initiate processes appropriate to the situation. This also explains the sometimes contradictory functions of serotonin in the organism.

The happiness hormone in the brain

Serotonin is often referred to as the happiness hormone. However, its functions in the brain are far more diverse. As already mentioned, it cannot cross the blood-brain barrier but must be produced locally. Tryptophan from food is necessary for this, as it can enter the brain via transporters.

Improve mood

Researchers have found that low tryptophan and serotonin levels are common in depression, and this is precisely what lowers mood. Serotonin promotes a feeling of calmness and reduces anxiety and aggression. Besides serotonin, dopamine, oxytocin, and endorphins are also known as "happiness hormones." Therefore, serotonin alone is not responsible for a good mood. All of these neurotransmitters need to be in balance for you to feel content and in a positive mood.

Its significance in the sleep-wake cycle

A good night's sleep is often a prerequisite for a good mood. Serotonin plays several roles in the sleep-wake cycle.

• Serotonin, along with cortisol, is the counterpart to melatonin. The first two neurotransmitters ensure that we are awake. Melatonin, on the other hand, is released in the evening and at night. It makes us sleepy and promotes restful sleep. For this reason, melatonin is also known as the sleep hormone. These processes are significantly influenced by light. Daylight makes us awake, and darkness makes us tired.
• Melatonin is produced from serotonin. Therefore, serotonin levels naturally decrease when high melatonin production is high. Many people notice this during the darker months of the year. The increased melatonin production combined with reduced serotonin production due to low light levels can be a cause of the winter blues.

The influence on our appetite

The amount of serotonin in the brain is indirectly related to our diet. When protein or tryptophan is consumed along with carbohydrates, the tryptophan concentration in the brain increases, allowing serotonin to be produced there. This means that sufficient serotonin in the brain has an appetite-suppressing effect.

Other function in the brain

This neurotransmitter is an antagonist to dopamine in relation to sexual behavior. It is released in the brain during ejaculation and has an inhibitory effect on male sexual behavior. Serotonin also plays a role in regulating body temperature, raising or lowering it depending on the situation. Serotonin can also have a bidirectional effect on pain, either amplifying or diminishing the pain stimulus.

Serotonin in the periphery

Besides its numerous effects on the brain, serotonin also influences the cardiovascular system, blood clotting, and the gastrointestinal tract. The latter is of particular interest to scientists due to research on the gut microbiota and the gut-brain axis.

Impact on the cardiovascular system

The effects on the cardiovascular system are complex. Depending on the tissue, serotonin leads to either dilation or constriction of blood vessels. In the kidneys and lungs, it causes vasoconstriction, while in the muscles, it causes dilation. Furthermore, blood pressure is indirectly influenced by this neurotransmitter.

Serotonin and blood clotting

Platelets are necessary for blood clotting. However, they also serve as storage for serotonin and themselves possess receptors that respond to this neurotransmitter. Serotonin enhances blood clotting and contributes to wound healing.

Functions in the gastrointestinal tract

Our intestines are constantly in motion. This is called peristalsis and ensures that the food pulp is continuously moved downwards. Serotonin release is mediated by high internal pressure, such as after a large meal. In addition to this motor function, serotonin also has a sensory function. High concentrations can lead to nausea and vomiting. This is, for example, the reason for vomiting as a side effect of chemotherapy, as increased serotonin is released in the intestines during this time. Furthermore, signals from the gut are transmitted. Some studies suggest that changes in gut bacteria can alter the effects of serotonin, and vice versa. For example, it has been shown that serotonin can reduce the number of pathogenic bacteria in the gut.

Serotonin deficiency - what are the underlying causes?

The many functions of the happiness hormone serotonin make it clear how detrimental a serotonin deficiency can be for the body. To avoid this, it's helpful to understand the causes, as you can directly influence some of them.

• Prolonged stress reduces serotonin production. Therefore, stress management strategies can have a positive effect on an imbalance in serotonin levels.
• Vitamin B6 is essential for the production of the messenger substance. Therefore, a deficiency of this vitamin could be a cause.
• You're not getting enough tryptophan. This amino acid is only found in a few foods and can best cross the blood-brain barrier in combination with carbohydrates.
• Your body is deficient in vitamin D. This is most common in winter, because vitamin D is produced in the skin when exposed to sunlight. In winter, the sun rarely shines, and even when it does, its intensity is too weak to promote vitamin D production.
• Certain diseases such as cancer, chronic infections and autoimmune diseases can cause a serotonin deficiency.

Serotonin deficiency - symptoms

Many people immediately think of depression when they hear about a serotonin deficiency. However, when this neurotransmitter is lacking, other symptoms are also possible. The following symptoms have also been reported in cases of serotonin deficiency:

• Anxiety
• Lack of motivation and increased fatigue
• bad mood
• mild irritability
• hypersensitive pain perception
• increased aggression
• nervousness
• Panic attacks
• Headaches and muscle pain
• reduced feeling of satiety
• Concentration problems
• High blood pressure

Furthermore, low serotonin levels appear to play a role in the development of some diseases. This is suspected, for example, in irritable bowel syndrome and migraines. The connection between serotonin and melatonin also explains why a serotonin deficiency can be responsible for sleep problems. Without serotonin, the sleep hormone melatonin cannot be produced, making it difficult to fall asleep and stay asleep.

Serotonin excess - what are the underlying causes?

A balanced hormone level is crucial for your health, and this is also true for serotonin. Both a deficiency and an excess of this hormone can cause health problems. The good news is that an excess doesn't just happen; it's only triggered under specific conditions.

If serotonin levels are significantly elevated, the so-called serotonin syndrome can develop. This is more of a combination of various symptoms than a classic illness. The serotonin excess is triggered by certain medications and must be treated quickly, as it can even be fatal. These medications are typically prescribed for depression, precisely when a serotonin deficiency is actually present. These antidepressants either increase the release of the neurotransmitter or inhibit its breakdown. The syndrome can occur either after the first dose of an antidepressant or after the dosage has been increased.

Significant excesses most often occur when interactions arise between different medications or drugs. Therefore, even natural substances like St. John's wort or tryptophan should not be combined with antidepressants without consulting a doctor. The same applies to some painkillers, migraine medications, the antibiotic linezolid, and drugs such as amphetamines, cocaine, and ecstasy.

Serotonin Syndrome: Symptoms

Since serotonin acts in both the brain and the rest of the body, the possible symptoms of a dangerously elevated serotonin level are also diverse. Initially, the syndrome can feel similar to a flu-like infection. However, more serious symptoms can develop within minutes. These include, for example, fever with chills, an increased pulse and blood pressure, an increased respiratory rate, profuse sweating, nausea, vomiting, and diarrhea, as well as headaches.

Since the interplay between muscles and nerves can also be impaired, so-called neuromuscular symptoms such as tremors, exaggerated reflexes, muscle cramps, and muscle twitches are possible. Serotonin syndrome also triggers symptoms in the brain. These include restlessness, hallucinations, and disturbances of consciousness and coordination.

The syndrome becomes seriously life-threatening when cardiac arrhythmias, irregular heartbeats, and epileptic seizures occur. Since serotonin also promotes blood clotting, blood clots can form in the organs, leading to organ dysfunction.

If you are taking antidepressants and notice symptoms of serotonin syndrome, you should seek medical attention immediately. Serotonin syndrome is dangerous and should not be taken lightly.

How can you increase your serotonin levels?

For most of us, however, the problem isn't an excess of serotonin, but a deficiency. Therefore, many people want to increase their serotonin levels, preferably naturally. In principle, this is possible, but if you have signs of serious depression, you need medical advice and shouldn't try various methods on your own.

How to increase serotonin levels!

 

• Summer, sun, sunshine: sunlight practically guarantees a good mood. So get out into nature! Even if clouds have moved in front of the sun, our bodies still register that it's daytime. Serotonin production increases, and melatonin release is reduced.

• Vitamin D: In summer, we can produce this vitamin in our skin, but unfortunately, this isn't possible in winter, making dietary intake crucial. It's also believed that the vitamin itself has a mood-boosting effect. What is certain, however, is that it's necessary for the production of serotonin. Vitamin D activates the first step in the synthesis process, converting tryptophan into 5-HTP.

• Sport and exercise: It's no secret that exercise improves mood. This has even been scientifically proven. One reason for this could be the increased serotonin levels resulting from exercise.

• Tryptophan & Carbohydrates: For your body to produce serotonin in the brain, tryptophan must cross the blood-brain barrier. This isn't so easy, however, as the amino acid competes with other amino acids for passage. In a protein-rich diet, tryptophan usually loses out because it is generally present in relatively small amounts compared to other amino acids. If you consume carbohydrates at the same time, your body releases insulin, and through complex metabolic pathways, this leads to more tryptophan crossing the blood-brain barrier. The key to a good tryptophan concentration in the brain is therefore to combine tryptophan-rich foods with carbohydrates.

• Healthy diet: Your diet has a significant impact on your serotonin levels, because your body can only produce optimal serotonin if it contains sufficient amounts of B vitamins, healthy fatty acids, and minerals. Pay particular attention to vitamin B6, vitamin D, omega-3 fatty acids, and magnesium. A vegan diet can also be deficient in vitamin B12, so you should supplement it for your health and a balanced mood.

Increase serotonin with foods

Foods containing serotonin, or products that already contain serotonin, are only partially effective in increasing serotonin levels, because this neurotransmitter cannot cross the blood-brain barrier. Therefore, they won't directly improve your mood. However, you can still prevent a serotonin deficiency with certain foods. We'll show you our top picks for balanced serotonin levels:

• Cocoa : The reason chocolate makes you happy is due to the cocoa it contains. Cocoa is a source of tryptophan. To really benefit from this, you should opt for cocoa powder , cocoa nibs, or dark chocolate. Milk chocolate and regular hot chocolate, on the other hand, contain very little cocoa but a lot of sugar.

• Bananas : They are perfect for increasing serotonin levels, as bananas score points with tryptophan in combination with carbohydrates. They also contain beneficial minerals and vitamin B6.

• Salmon : Here, too, a great combination comes together. Vitamin D, which is needed to activate serotonin production, meets healthy omega-3 fatty acids. This fatty acid is directly responsible for the release of serotonin.

• Nuts : If you're vegetarian or vegan, you can get omega-3 fatty acids from nuts such as walnuts. Nuts also boast a high tryptophan content, making them a smart snack to combat an afternoon slump.

• Cordyceps and other medicinal mushrooms: Dried mushrooms are rich in tryptophan. By consuming medicinal mushrooms daily, you're indirectly boosting your mood, as they contain the precursor to serotonin. Our Mushroom Cacao contains not only the medicinal mushroom Cordyceps, but also cocoa and vitamin B5 – a clever combination! :-)

Serotonin: Everything at a glance

Serotonin is a neurotransmitter that performs many different functions in the body. Its best-known function is mood regulation, which is why serotonin is also called the "happiness hormone." It is therefore not surprising that serotonin levels in the body can be reduced in cases of depression.

The causes of a serotonin deficiency are varied. However, poor nutrient intake and insufficient sunlight are possible contributing factors. A serotonin deficiency can manifest in various symptoms, including anxiety, headaches, and more. However, too much serotonin can also be harmful. Antidepressants or a combination of different medications can cause serotonin levels to rise too high. This is dangerous and requires medical attention.

However, a deficiency is possible for significantly more people. You can counteract a serotonin deficiency through a healthy diet, exercise, sun exposure, and a smart combination of carbohydrates and tryptophan. Unfortunately, direct serotonin from food cannot cross the blood-brain barrier, so the neurotransmitter must always be produced directly in the brain. The amino acid tryptophan, vitamin D, and vitamin B6 are necessary for this. Ideal foods for the body's own serotonin production include cocoa, medicinal mushrooms (ideally combined as mushroom cacao ), nuts, and more. They are real mood boosters :-)

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