9 Signs that Indicante Low Serotonin Levels in Your Body

Low serotonin levels can cause changes in your mental health, such as sadness, depression, irritability, trouble sleeping, and aggressivity.
9 Signs that Indicante Low Serotonin Levels in Your Body
Mario Benedetti Arzuza

Written and verified by the doctor Mario Benedetti Arzuza.

Last update: 25 May, 2022

Having a low level of serotonin in the body translates into discomfort ranging from mood swings to digestive and cardiac symptoms. This neurotransmitter, as detailed in a publication in The National Center for Biotechnology Information, is involved in the regulation of behavior, memory, and various physiological functions.

Therefore, when serotonin levels are low, the body undergoes changes that manifest with physical and emotional discomfort. Thus, sadness, irritability, lack of concentration, and sleep disorders, among others, may indicate that your levels are low. Do you want to know more about it? Keep reading!

What is serotonin?

Serotonin is a chemical produced by nerve cells. It acts as a neurotransmitter and its main function is to modulate neuronal activity and a wide variety of neuropsychological processes. Likewise, and according to what was disclosed in the Annual Review of Medicine, it intervenes in biological functions such as the following:

  • Cardiovascular function
  • Gut mobility
  • Ejaculatory latency
  • Bladder control

Most serotonin is found outside the central nervous system, such as in the digestive system and blood platelets. In addition, it’s made of an amino acid called tryptophan, which is obtained through foods such as nuts, cheeses, and meats. If there are low levels of tryptophan, it also tends to lower serotonin. Consequently, the body experiences physical and psychological symptoms.

Serotonin plays an important role in multiple physical and psychological functions. Thus, if its levels decrease, the body manifests various symptoms.

The main functions of serotonin

As a neurotransmitter, the main function of serotonin is to carry messages from one area of ​​the brain to the other. Thus, it intervenes both in emotions and in cognitive functions and motor skills. In particular, it affects the following processes and functions:

  • Control depression and anxiety.
  • Increase the feeling of well-being.
  • Stimulate wound healing.
  • Regulate nausea.
  • Maintain bone health.
  • Control bowel movements and their function.
  • Stimulate the parts of the brain that control sleep and wakefulness.
  • Influence sexual function.

Signs of low serotonin levels

Sometimes, imbalancesin the body are linked to a decrease in serotonin levels. Of course, it is a situation that must be determined by a doctor or specialist. Even so, it’s convenient to know some symptoms that can help detect it in a timely manner. Take note!

1. Mood disorders

Studies suggest that low serotonin levels play a role in increased anxiety. This is because this substance largely regulates impulses and emotions. In this sense, its decrease is also linked to the following disorders:

2. Digestive problems

Serotonin isn’t just associated with digestive processes: in fact, 95% of it is found in your intestines. This is because having too little of this hormone can directly affect your gastrointestinal system, to the point of even developing irritable bowel syndrome. When you increase its levels, however, your condition will return to normal.

Maybe you’re interested in What is generalized anxiety disorder?

3. Cognitive deterioration

Beyond its impact on mood, serotonin affects relevant cognitive processes such as memory. Thus, as evidenced by a study shared in Translational Neuroscience, low levels of serotonin are linked to diseases such as Alzheimer’s and schizophrenia.

4. A need to eat carbohydrates

If a person has low serotonin, it’s normal for their body to try to compensate while eating carbohydrates and sweets. These foods help increase the levels of this neurotransmitter in the brain. For that reason, the person experiences a lot of satisfaction when eating foods that are full of sugar.

5. Fatigue

In addition, when serotonin levels are lower than they should be, it starts to affect your daily activities and can lead to fatigue. Therefore, it’s common for people who suffer from low serotonin to experience feelings of:

  • Apathy
  • Lethargy
  • Fatigue
  • Lack of energy
  • Lack of motivation


Emotional hypersensitivity could be because of low serotonin levels

As most people know, this hormone is directly associated with emotional stability. A low level can cause you to be more sensitive than usual. It might reach the point in which any comment or slight feels worse than it actually is.

4. Serotonin and carbohydrates

A panorama of junk food.

The body of a person with low levels of serotonin will try to compensate by eating sweets and carbs. In addition, these types of food increase the levels of this hormone in the brain.

That’s why you feel so satisfied when you eat foods that are full of sugar — y our levels increase significantly.

5. Fatigue

In addition, when serotonin levels are lower than they should be, it starts to affect your daily activities and can lead to fatigue. Therefore, it’s common for people who suffer from low serotonin to experience feelings of:

  • Apathy
  • Lethargy
  • Fatigue
  • Lack of energy
  • Lack of motivation
Fatigue serotonin
A constant sensation of fatigue and weakness may be a sign of low serotonin levels.

6. Libido

Uncontrolled serotonin levels have a negative impact on libido. Although its decrease is usually associated with a greater sexual desire, it also reduces the ability to connect emotionally with the partner, which translates into unsatisfactory relationships.

7. Difficulty falling asleep

A low level of serotonin affects the appearance of sleep disorders. As a study in Sleep Medicine Reviews explains, serotonergic neurotransmission plays an important role in modulating circadian rhythm, sleep, and wakefulness. Therefore, if the hormone decreases, the following symptoms occur:

  • Insomnia
  • Constant nightmares
  • Inability to relax
  • Trouble sleeping
  • Difficulty obtaining deep sleep
  • Trouble staying asleep at night

8. Low self-esteem

If a person suddenly has low self-esteem, feelings of frustration, or dissatisfaction with oneself, it’s possible that a low level of serotonin is present. Although many ignore it, this neurotransmitter is also key to feeling well with oneself. The lack of self-esteem is also manifested in comparisons, hypersensitivity to criticism, and lack of confidence, among other things.

Research suggests that lowered levels of serotonin worsens chronic pain and disorders like fibromyalgia.

Do you think you could have low serotonin levels?

If you’ve just recognized these symptoms and believe that you have a low serotonin level, it’s best to seek professional attention. The doctor, after carrying out the corresponding tests, will determine if it’s necessary to take medications (such as selective serotonin reuptake inhibitors) or if it’s enough to improve your diet and lifestyle.

Of course, in the case of depression and mood disorders, psychological help is also essential. Thus, it may be that the problem requires a multidisciplinary approach. Therefore, it’s necessary to consult a professional as soon as possible.

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.

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