7 Warning Signs of Low Serotonin Levels

7 Warning Signs of Low Serotonin Levels
Gema Sánchez Cuevas

Reviewed and approved by the psychologist Gema Sánchez Cuevas.

Last update: 21 December, 2022

Adequate levels of serotonin in the brain help us feel positive, happy, calm, and safe. Low levels of this neurotransmitter can lead to negative or worried feelings and irritability. A serotonin deficiency can make you feel pessimistic, sad, mistrustful, or even cause a panic attack. It can lead to depression, anxiety, and other health problems. Today we will discuss signs of low serotonin.

Serotonin acts as a neurotransmitter, which is a type of chemical that helps transmit signals from one area of the brain to another.  This neurotransmitter is a powerful brain chemical, and its presence or absence has a great influence on our mood. Determining if the neurons are not releasing or receiving enough is the first key step in overcoming problems related to impulse control and mood.

With proper levels of serotonin, the brain can function properly.

This neurotransmitter has many functions in the brain and the body. In the brain, it regulates mood, social behavior, libido, sleep, memory, and learning.

What does serotonin do?

As a neurotransmitter, serotonin helps convey messages from one area of the brain to the another. Due to the wide distribution of cells that have serotonin receptors, it is believed that serotonin levels influence different psychological functions as well as the regulation of physiological processes.

This means that of the approximately 40 million cells in the brain, the majority are influenced directly or indirectly by serotonin. This includes brain cells related to mood, desire, sexual function, appetite, sleep, memory, learning, temperature regulation, and some social behaviors. In terms of body function, this neurotransmitter can also affect the cardiovascular system, muscles, and different elements of the endocrine system, among others.

Signs of low serotonin

The relationship between serotonin and depression

There are many researchers who believe that a serotonin imbalance can influence mood to such an extent that it could cause depression. Possible problems include:

  • Low serotonin production in brain cells
  • Lack of receptor sites capable of receiving the serotonin that is produced
  • Inability of serotonin to make it to receptor sites
  • A scarcity of tryptophan, an essential amino acid necessary to synthesize serotonin.

Researchers believe that any of these biochemical failures could cause depression, obsessive-compulsive disorder, anxiety, panic attacks, or even excessive anger. However, there is still a lot of research to be done on the link between serotonin and depression.

Do my neurons release enough serotonin?

Being able to identify a serotonin deficiency can help measure and take action to raise serotonin levels. So even though depression and subsequent joylessness are the most well-known signs of low serotonin, they certainly aren’t the only ones. In fact, recognizing other signs and symptoms can help us prevent depression, anxiety, and worse.

Symptoms of serotonin deficiency include frequent anger, unusual sensitivity to pain, carbohydrate cravings and binges, constipation, and digestive disorders. Other signs and symptoms are: feeling unwell due to lack of sunlight, feeling overly dependent on others, feeling overwhelmed, insomnia, migraines, low self-esteem, and poor cognitive function, among others.

We will now analyze some of the most important signs that indicate low serotonin levels. These signs are important because they are the easiest to detect at an early stage.

Cravings for sweets and foods high in carbohydrates

It is well known that carbohydrates, especially sweet and starchy foods like pastries, chocolates, fruity candy, french fries, hamburgers, and other snacks, directly impact serotonin levels. That’s why people with low serotonin levels often crave carbohydrate-rich foods and eat compulsively.

These foods temporarily raise serotonin levels and make you feel better. However, shortly after consumption, serotonin levels drop drastically. This dramatic decrease in serotonin leads to drowsiness, hostility, anxiety, and depression.

Insomnia

The amount of available serotonin also directly affects melatonin production. When serotonin levels are low, melatonin production is also affected. This domino effect ends up altering the circadian rhythm.

When this happens, it is extremely difficult for a person to follow the natural sleep-wake pattern. Specifically, the ability to fall asleep and stay asleep is negatively affected. Don’t forget, however, that insomnia can have other causes as well, not just serotonin deficiencies.

Serotonin must be available to be converted into melatonin, the hormone responsible for managing our biological clock

Anxiety

Through the observation of brain images, researchers have shown that frequently anxious people release a lower amount of this chemical substance in the areas of the brain responsible for impulses and emotional control. 

signs low serotonin

It is worth mentioning that insufficient release of this important neurotransmitter is generally not the only factor in the development of anxiety disorders, although some people have a genetic predisposition to low serotonin levels. In reality, there are three other neurotransmitters, gamma-aminobutyric acid, dopamine, and epinephrine, that also play a role in anxiety disorders.

Low serotonin is associated with generalized anxiety disorder, panic disorder, and obsessive-compulsive disorder.

Cognitive deterioration

Serotonin is an important chemical for normal cognitive function. Research has shown that sufficient levels of this neurotransmitter improve cognitive ability and can help to compensate for limited cognitive function.

Though it is believed that serotonin plays a role in all thought abilities, its most significant impact is on memory. People with low levels of serotonin are more likely to have problems with memory consolidation.

Digestive problems

Serotonin is an important chemical in the transmission of signals between the brain and the digestive system. It is worth pointing out that, although this neurotransmitter is almost always associated with brain function, mood, and mental well-being, a surprising 95% of serotonin is produced in the gut, not in the brain. However, serotonin used by the brain must be produced in the brain because serotonin produced in the intestine does not travel to the brain.

Nevertheless, while research about the function of serotonin in the gut is relatively new, we know that it plays an important role in appetite and digestion. In fact, the reason that there is so much serotonin activity in the gut is still somewhat of a mystery.

In addition, scientists have discovered a link between Irritable Bowel Syndrome and insufficient levels of serotonin. It has been shown that when the insufficiencies are corrected, the digestive function in people with Irritable Bowel Syndrome often returns to normal.

Fatigue or exhaustion

Serotonin levels play an important role in energy production. Some people who experience chronic fatigue show insufficient levels of this chemical substance. When serotonin levels are replenished, people suffering from fatigue often notice a marked improvement in their energy levels.

While feeling fatigued or exhausted could be the result of many different conditions, don’t eliminate the possibility that there could be a serotonin-release problem. In the long-term, chronic fatigue increases the possibility of a reduction in serotonin release.

Changes in libido

Among the many properties of serotonin is its effect on libido (sexual desire). Low levels of this chemical substance are directly related to a greater desire to have sex, but also with a decrease in the ability to emotionally connect with the other person. This is not a good recipe for a satisfying relationship.

In addition, fluctuations in serotonin levels can affect attitude, not to mention the physical abilities related to sexual activity.

What to do if you have low serotonin levels

If at all possible, try to increase your serotonin levels in a natural way, without medication. Here are some ways to increase your levels:

  • Get moving with activities that you enjoy. Do exercise that allows you to have fun, not suffer.
  • Eat protein-rich foods that contain tryptophan.
  • Eat carbohydrate-rich foods like vegetables, dried fruits, beans, and whole grains (the brain needs sugars to process tryptophan). You don’t need too many carbohydrates, so eating vegetables, dried fruits, rice, and legumes will give you what you need.
  • Avoid foods high in saturated fat and simple sugars.
  • Eat foods rich in Omega-3 for optimal brain function.
  • Limit your caffeine consumption.
  • Get enough sleep.
  • Eat foods rich in B-vitamins, especially Vitamin B6 (this vitamin is important for the development and function of serotonin in the brain).
  • Spend time outside and get plenty of sunshine.
  • Practice meditation and mindfulness.

As we have seen in this article, serotonin is a neurotransmitter that plays an important role in your health. Serotonin-release deficiency can seriously compromise very important processes such as emotional regulation and sleep. 


All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.


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This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.