Are you struggling with your mood or having a bad sleep a bit too often? Have you noticed changes in your digestion, but don’t know why? This might be a sign of low levels of serotonin.
If you’re having low levels of serotonin, you may experience changes in your mood, sleep, brain cognition like memory and learning, sex drive or digestive issues. Studies suggest that low serotonin may lead to depression, but the thesis is not completely proven right, since other factors such as genetics may play a role as well. As a health coach, who has had low serotonin levels myself, I’ll personally recommend the OrganiX test that measures neurotransmitter metabolism such as serotonin. Increasing serotonin may be possible through diet changes, exercise, sunlight exposure and supplementation.
In order to address how to know if you’ve low serotonin levels, we’ll talk about what serotonin is, symptoms, causes, test methods and how to increase serotonin levels.
What Is Serotonin?
Serotonin is also known as 5-hydroxytryptamine (5-HT) and is a neurotransmitter that carries messengers between nerve cells in our brain through the nervous system. Serotonin is primarily created in our digestive tract – up to 90% and around 10% in our brain/central nervous system.
Serotonin is involved in multiple activities in our body such as regulating:
- Mood
- Memory
- Sleep
- Digestion
- Regulate anxiety
- Sex drive
- Hunger
- Learning
According to PubMed Central, serotonin plays a role in mood disorders and depression.
Serotonin is synthesized from the amino acid tryptophan, which undergoes different processes and turns into 5-HTP and then essentially forms 5-HT.
Serotonin is both synthesized and stored in the central nervous system (CNS) in serotonergic neurons, the pineal gland and catecholaminergic neurons.
In CNS, serotonin is processed in multiple ways, for example in the synaptic cleft where serotonin either binds to postsynaptic serotonin receptors (5-HT receptors) or presynaptic serotonin autoreceptors.
When serotonin binds to autoreceptors, it acts as a negative feedback against releasing more serotonin in the synaptic cleft. The serotonin transporter, called SERT, is located in the presynaptic membrane and removes serotonin from the synaptic cleft.
When serotonin is transported into the presynaptic neuron, serotonin finds its way back to the presynaptic vesicles, where it is protected from being metabolized. The metabolism happens in the cytoplasm of the neuron by monoamine oxidase (also called MAO). Alternatively, serotonin converts to melatonin (our sleep hormone) in the pineal gland.
As mentioned earlier, 90% of serotonin is found in our gut – more specifically in enterochromaffin cells. The remaining 10% is found in the central nervous system, which controls sleep, hunger, mood, etc.
While high levels of serotonin released from enterochromaffin cells in the gut contract vascular smooth muscle cells leading to vasoconstriction – low levels of serotonin release nitric oxide leading to vasodilation. This may lead to changes in blood pressure and blood clotting.
This means, according to PubMed Central, that serotonin regulates bowel function, nervous system regulation and mood, blood flow, blood clotting, and sexual function.
Personally, I think that our gut health and serotonin production is correlated. Studies made from PubMed Central point to the fact that alterations of specific bacteria in the gut microbiota, may contribute to a modulation of serotonin signaling.
Low serotonin levels may lead to several manifestations in our body – but how do you know which symptoms to look out for?
Low Serotonin Symptoms In Females
Low levels of serotonin can manifest as different symptoms in each individual. According to Clevelandclinic.org, some of the signs of low serotonin may include:
- Depression
- Mood swings
- Poor memory
- Cognitive changes
- Digestive issues such as IBS, constipation or diarrhea
- Appetite issues
- Insomnia
- Phobias
- OCD
- PTSD
- Panic attacks
Disclaimer: If you’re suspecting low levels of serotonin, I’ll recommend you talk to your healthcare provider, as this is not a medical site, but purely general information.
Some individuals may be more affected than others – low serotonin doesn’t equal being affected by the above-mentioned. However, I personally think that low serotonin will affect mood, brain function and digestion in one way or another.
According to studies, low levels of serotonin (5-HT) may be connected to depression, and early life stress may interfere with serotonin signaling and play a role in anxiety and impulsivity-related behaviors.
The “serotonin hypothesis” of establishing clinical depression is known as low serotonin may equal depression. However, I don’t believe it’s that simple.
According to a study, made by PubMed Central, depression may stem from tryptophan depletion, where low levels of tryptophan equals low levels of brain serotonin activity.
In healthy participants, low levels of tryptophan do not necessarily equal significant changes in mood or depression. However, the evidence suggests that low levels of serotonin may cause clinical depression in some circumstances – but it depends on prior episodes of depression and the ‘family history’ as well.
This means, according to the research, that there’s no clear evidence of the “serotonin hypothesis” that low tryptophan or serotonin equals depression, due to lack of substantial research. However, I believe low serotonin affects our mood in one way or another.
What Causes Low Serotonin?
There are multiple factors related to low levels of serotonin. As the “serotonin hypothesis” may suggest that inadequate amounts of tryptophan may lead to low serotonin and depression – our serotonin levels may also be affected by:
- Chronic stress
- Genetic factors
- Poor diet choices
- Drugs and toxins
- Hormonal changes
As mentioned earlier, early life stressors or in general chronic stress may lead to depleted serotonin levels. Chronic stress takes a toll on our body and can dysregulate mood, cognition and physiological function.
A study suggests that cortisol (stress hormone) may increase the expression of the gene coding for the serotonin transporter – but under chronic stress, the capacity of serotonin transporters was limited due to high blood cortisol.
Poor diet choices not containing enough proteins, vitamins and minerals along with caffeine, alcohol, heavy metals and drug use may interfere with the production of serotonin as well. This also affects digestion which may interfere with the microbiota.
If you’re thinking you have low levels of serotonin due to the information you’ve gathered so far, how do you test your serotonin levels, you might think?
How Do You Check Serotonin Levels?
Personally, I’ve had low levels of serotonin myself and have had symptoms like low mood, sleep problems, food cravings, anxiety and chronic digestive issues. It’s difficult to prove if it’s only due to low serotonin levels or other factors as well.
However, besides consulting with a specialist I took the OrganiX test that measures 45 markers of organic acids on a cellular level. These include metabolism, B-complex vitamins, neurotransmitters, antioxidants, oxidative stress and gut dysbiosis.
The test indicated that my serotonin levels were low amongst other factors as well – and through analysis, I could figure out how to improve my serotonin deficiency.
How Do You Fix Serotonin Deficiency?
When it comes to serotonin imbalance there might be a few ways of increasing serotonin naturally.
As mentioned earlier, tryptophan is the precursor of serotonin (5-HT), as why increasing tryptophan-rich foods in your diet or as a supplement may help increase serotonin levels.
Tryptophan-rich foods include:
- Whole milk
- Turkey
- Chicken
- Tuna
- Cheese
- Nuts and seeds
- Banana
- Prunes
- Dark chocolate
- Tofu
- Beans
However, I personally don’t recommend whole milk and cheese as it may increase inflammation.
Furthermore, take care of your gut health with probiotic and prebiotic foods along with fibers. A healthy gut needs lots of the ´good’ bacteria which you may increase through a probiotic supplement and fermented foods.
Some natural supplements may also increase serotonin. This includes 5-HTP. Tryptophan is converted into 5-HTP and then into 5-HT – serotonin. It is said that up to 70% of 5-HTP will be absorbed and cross the blood-brain barrier.
Disclaimer: If you’re considering taking any kind of supplement, I’ll recommend you talk to your healthcare provider, since supplements may lead to side effects.
Other factors such as exercise, sunlight exposure, and lowering stress levels may help increase serotonin levels.
Final Thoughts
If you’re having low levels of serotonin, you may experience symptoms like low mood, depression, anxiety, digestive issues and insomnia – however, each individual may experience different effects of low serotonin.
Studies suggest that low levels of serotonin may lead to depression, but it also depends on genetic factors, stress, digestive issues, etc.
If you’re suspecting you’ve low levels of serotonin, I’ll recommend you to test it through an OrganiX test and consult with a specialist.
However, some simple ways you may increase serotonin levels are through exercise, tryptophan-rich foods, probiotics to support gut health and daily sunlight exposure.
