Since serotonin is primarily associated with feelings of happiness, if there are low serotonin levels, it makes sense to believe this would contribute to lower happiness levels.
Many symptoms are associated with low levels of serotonin. Some of these include feeling low in mood, anxious feelings, irritability, feelings of depression, and low self-esteem.
Low serotonin levels have been associated with some mental health conditions, mostly mood disorders. If symptoms of low serotonin persist, this risks the development of conditions such as depression.
Depression is associated with sadness, hopelessness, and sometimes suicidal thoughts. Other mental health conditions have also shown associations with low serotonin, such as anxiety disorders and schizophrenia.
Low serotonin levels could be caused by a few factors. It could be that not enough serotonin is being produced in the brain. Another potential cause of low serotonin can result from insufficient serotonin receptors in the brain, or these receptors are not functioning as they should.
As a result of these issues, it could be the case that too much serotonin is being broken down in the synaptic cleft by enzymes or reabsorbed back into the presynaptic neuron at an excessive rate.
Also, if not enough serotonin is produced in the first place, this limits the amount reaching the serotonin receptors of the postsynaptic neuron.
In This Article
Increasing Serotonin Naturally
There is evidence that lifestyle changes and other non-medicative methods can improve the levels of serotonin naturally in the brain. Usually, medication is recommended for individuals who are suffering from a clinical mood disorder, and therefore the symptoms of low serotonin are typically more severe.
However, being able to prevent people from getting to a stage where symptoms are severe is preferable to waiting until they are at a stage where they require medication.
The use of medication is not always appropriate for some individuals who may only be experiencing mild symptoms of low serotonin or in children and adolescents, where these medications or not usually recommended due to risky side effects in these populations.
Nonmedicated methods of raising brain serotonin may not only improve mood but may also help protect against the onset of various mental health conditions.
Exercise
One method that has shown evidence of increasing serotonin levels in individuals is exercise. Exercise has been shown to improve the moods of people with clinical mental health problems, as well as those who only show mildly depressed symptoms.
The most consistent effect observed was when individuals would undertake aerobic exercises such as running, walking, cycling, and swimming. It has also been found that completing aerobic exercise until fatigued is associated with elevated levels of serotonin being produced.
There has been a change in the level of vigorous physical exercise that is required since humans were hunter-gatherers or mostly worked in agriculture.
It has been suggested that this decline in vigorous physical exercise on a daily basis may contribute to why there are a higher number of people with depression in today’s society.
Diet and supplements
Tryptophan is an essential amino acid that can be converted into serotonin in the brain and can only be accessed through foods. As this amino acid can be converted into serotonin, this makes it a key element for brain functioning, potentially having a positive impact on mood.
Tryptophan is primarily obtained from animal or plant-based protein sources, however it can come as a supplement on its own. Tryptophan supplements contain much more tryptophan than food, with evidence finding that these supplements can have the same effect as antidepressants do on women.
It has also been found that not only a diet rich in tryptophan, but also a diet rich in antioxidants can have a positive impact on mood and cognition.
Another supplement worth mentioning is 5-HTP.
This is a supplement that can produce more serotonin in the brain. In a study of those with early symptoms of depression, 5-HTP supplements were found to have an antidepressant effect in these individuals after two weeks of treatment.
The therapeutic effects of this supplement were considered equal to that of fluoxetine, an SSRI.
Light therapy
Exposure to bright light is a second possible method for increasing serotonin without medication. Being in the sunlight can produce vitamin D, which plays a role in the body, promoting serotonin production.
Although too much sunlight and exposure to UV rays can be harmful to the skin, it is understood that some sunlight every day can help alleviate low moods.
As was the case already discussed for exercise, in the past, more people were involved in agriculture and were outside for much of the day. This would have resulted in high levels of bright light exposure even in the winter, which may be a contributing factor for why depression appears to be more common these days.
Bright light, in the form of a SAD light for instance, is a standard treatment for those suffering with seasonal depression.
However, some studies have suggested that it is an effective treatment for non-seasonal depression as well.
Increasing Serotonin with Medication
Medications for increasing serotonin levels, particularly antidepressants, have been prescribed to treat conditions such as depression and anxiety.
These medications work by causing a direct influence on the brain chemistry involved in neurotransmission. The most commonly used antidepressants which affect serotonin levels are selective serotonin reuptake inhibitors (SSRIs), tricyclic antidepressants (TCAs), and monoamine oxidase inhibitors (MAOIs).
Selective serotonin reuptake inhibitors (SSRIs)
SSRIs are the most prescribed antidepressant medication to increase levels of serotonin in the brain. This medication is typically prescribed to treat the symptoms associated with conditions such as depression and anxiety.
SSRIs work by blocking the reabsorption of serotonin, therefore preventing the reuptake of this chemical by the neuron which released it. As this medication is preventing serotonin from being reabsorbed back into the presynaptic neuron, this means there will be more serotonin circulating around the synaptic cleft.
If there is more serotonin in the synaptic cleft, this makes it more likely that serotonin will reach the receptors on the postsynaptic neuron, meaning that serotonin has a better chance of traveling around the brain and improving mood.
SSRIs are the most common treatment for increasing serotonin levels because they have the least negative side effects compared to other medications which work in a similar manner, making SSRIs more tolerable.
There are, however some side effects that could be experienced as a result of taking this medication. Some side effects may include headaches, nausea, change in weight, sexual dysfunction, sleep problems, and agitation.
Tricyclic antidepressants (TCAs)
TCAs are an older classification of antidepressants compared to SSRIs and are less prescribed. This medication works in a similar way to SSRIs as they also work to block the reuptake of serotonin.
TCAs also block the reuptake of another neurotransmitter called norepinephrine, also known as noradrenaline, which also affects mood. Although this medication works similarly to SSRIs, they are believed to be not as tolerable due to their many side effects.
Some side effects that could occur as a result of taking this medication are fatigue, headaches, disorientation, sexual dysfunction, irregular heart rate, and weight gain.
Aside from these side effects, it is often not recommended that alcohol is consumed whilst also taking this medication since alcohol can counteract the TCAs effects.
Also, some other medications can have adverse reactions when taken alongside TCAs such as EpiPens, which are filled with adrenaline. Using an EpiPen alongside TCAs could result in heart rhythm problems and high blood pressure.
Likewise, TCAs are known to increase blood sugar levels, meaning that there would be a high risk to those who have diabetes if they were to take this medication.
As TCAs can also affect the heart rhythm, those who have existing heart problems would probably not be prescribed this medication.
Monoamine oxidase inhibitors (MAOIs)
Another older type of antidepressant that is used to increase serotonin levels are MAOIs. This medication works differently to SSRIs and TCAs, which block serotonin reuptake.
Instead, MAOIs affect the enzyme which breaks down the serotonin in the synaptic cleft, known as monoamine oxidase. MAOIs work by preventing serotonin from being destroyed by monoamine oxidase.
If serotonin is not destroyed by this enzyme, this means that there will be more serotonin circulating around the synaptic cleft, making it more likely that serotonin will reach the receptors on the postsynaptic neuron.
This type of medication is not typically used as the first option for people with low levels of serotonin due to the strong side effects associated with taking this.
Some of the side effects include nausea, dizziness, insomnia, and restlessness. MAOIs can also have an effect on other neurotransmitters in the brain unintentionally, which can cause other unwarranted side effects.
This medication also comes with dietary precautions that need to be followed when taking the medication as they can cause adverse reactions when taken in combination with certain foods.
Foods and drinks that should be avoided include alcohol, strong cheeses, cured and processed meats, and soybeans.
Finally, MAOIs could have negative reactions when mixed with other medications and, in some rare cases, can also cause dangerously high levels of serotonin, known as serotonin syndrome.
Too Much Serotonin
Although increasing serotonin levels is beneficial for improving mood and treating some mental health conditions such as depression, a surplus of serotonin in the brain can be detrimental.
Having too much serotonin in the brain can result in a condition known as serotonin syndrome. Often, serotonin syndrome can result from some medications that are being taken to increase low serotonin levels.
This can sometimes arise after taking MAOIs and TCAs. Serotonin syndrome typically occurs after starting to take a new medication, or when the dosage of an existing medication has increased. Some of the symptoms associated with serotonin syndrome can be quite mild.
These can include high blood pressure, headaches, restlessness, confusion, and shivering. These mild symptoms of serotonin syndrome may go away within a day or two of stopping the medication that is causing symptoms, on the advice of a doctor.
However, if this is not treated, then the symptoms can become worse. Some of the worst symptoms can include irregular heartbeat, seizures, unconsciousness, and may sometimes even result in death in the most severe cases.
To help prevent serotonin syndrome from occurring, it is advised to talk through all the side effects of medications with a doctor before they are prescribed.
Also, a doctor may advise starting with a small dosage of the medication to see how they get on with this, before looking to increase the dose.
What is serotonin?
- Serotonin is a neurotransmitter, which is a chemical messenger in the brain, that is associated primarily with feelings of happiness.
- Serotonin’s role in the brain is of interest to psychologists as it is thought to contribute to many important functions such as playing a role in mood, especially in terms of mental health conditions associated with moods, such as depression and anxiety.
- Serotonin is key in modulating mood, considered to be a natural mood stabilizer. This neurotransmitter is believed to help individuals with feeling calm, and emotionally stable and is thought to help regulate anxiety and reduce depressed feelings.
- Serotonin also has a role in many aspects of behavior, such as perception, attention, and aggression. Finally, serotonin is also believed to have a role in sleep and physical health.
- The scientific name for serotonin is 5-hydroxxytryptamine (5-HT). Serotonin is a neurotransmitter under the branch of monoamine neurotransmitter, chemicals that contain amino acids. Monoamine neurotransmitters have an important role in decision-making, happiness, rewards, and emotions.
- Serotonin is also classified as an inhibitory neurotransmitter since it has inhibitory effects on the neurons. This means that serotonin will decrease the likelihood that the neurons will fire an action potential. Thus, serotonin does not stimulate the brain, instead, it balances out the excessive excitatory effects of other neurotransmitters.
Serotonin Transmission
- Serotonin is projected to many areas of the brain including the lobes of the cerebral cortex, cerebellum, hippocampus, and spinal cord. First, serotonin is produced in the brain stem, in a cluster of nuclei called the Raphe nuclei.
- The serotoninergic fibers are then sympathized from these nuclei and projected to a region called the nucleus accumbens, an area of the brain which is known as the circuit area for rewards. Once at the nucleus accumbens, serotonin is then projected throughout the brain.
- During the transmission of neurons, also known as neurotransmission, serotonin is released from the presynaptic terminals of neurons into the synaptic cleft. Once in the synaptic cleft, serotonin will do one of a few things.
- It will either reach serotonin receptors on the postsynaptic neuron to continue down the next neuron via electrical impulses.
- If serotonin does not reach the receptors, it may be reabsorbed back up into the presynaptic neuron by serotonin transporters (SERT), or they will be broken down by an enzyme called monoamine oxidase, therefore being destroyed.
References
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