Tryptophan belongs to exogenous amino acids, essential, i.e. compounds that are not produced spontaneously in the body, therefore they must be delivered to it along with the diet. Tryptophan is necessary for the production of proteins, enzymes and muscle tissue. It regulates the work of the whole organism by engaging in processes essential to maintaining homeostasis that take place in the human body. It plays an extremely important role in the proper functioning of the nervous system, and its deficiencies cause irregularities in the nervous system, energy decline, worse well-being and even depression.

Tryptophan plays many important functions in the body, such as:

  • impact on the nervous system, regulation of neurotransmitters: noradrenaline, dopamine and β-endorphin,
  • participation in the creation of serotonin, the so-called hormone of happiness,
  • participation in the creation of melatonin – a hormone responsible for maintaining the normal circadian rhythm of the body,
  • participation in the creation of kynurenine – a chemical UV filter produced in the eyeball,
  • participation in the synthesis of rhodopsin – a photosensitive dye that allows night vision,
  • participation in the biosynthesis of vitamin B3 (niacin, vitamin PP),
  • mood regulation and reduction of tension and hyperactivity,
  • regulation of metabolism and carbohydrate metabolism,
  • improving immunity,
  • participation in the reproduction process,
  • effect on lactation.


Tryptophan and depression

Tryptophan in the brain is transformed into serotonin neurotransmitter known as the “happiness hormone”. Lack of adequate amount of tryptophan leads to deficiencies of serotonin in the body, resulting in decreased mood, anxiety, aggression, insomnia, increased sensitivity to pain, and ultimately depressive disorders. Serotonin also affects impulsive behavior, sexual needs and appetite regulation.


Symptoms of tryptophan deficiencies:

  • insomnia,
  • mood swings,
  • anxiety,
  • depression,
  • tendency to overeat and sadness.


Symptoms of excess amount of tryptophan:

  • insomnia,
  • feeling of dry mouth,
  • headaches,
  • nausea and vomiting.


Sources of tryptophan in food:

Tryptophan-rich products are protein products such as lean meats, fish, eggs, cottage cheese, milk, yellow and white cheese, soy products, pumpkin seeds. Large amounts of tryptophan are also found in legumes, spinach and fruit such as pineapple or bananas.Consuming food products containing tryptophan does not directly translate into serotonin concentration in the body, because the amount of tryptophan relative to other amino acids is too low to be well absorbed by the blood-brain barrier. Therefore, tryptophan obtained from food is less absorbed in comparison to other amino acids. Supplementation affects the increase in the level of tryptophan and its metabolites in the brain, while reducing the depressive states.


Supplementation with tryptophan:

Supplements which contain tryptophan:

L-tryptophan 500mg, 250 capsules (Lymeherbs) – product available here

Neurobiane 60 capsules (PiLeJe) – product available here



L-tryptophan supplementation should not be used by people also suffering from:

  • scleroderma,
  • bradycardia,
  • hypoglycemia,
  • cancer,
  • taking steroid hormones,
  • taking hormonal contraceptions.

Furthermore, pregnant and nursing women should also not take L-tryptophan supplements.