Tyrosine is a non-essential aromatic amino acid, that is, it is produced by the body from another amino acid, phenylalanine. It can also be obtained through foods, such as cheese, fish, avocado and nuts, and through nutritional supplement, such as L-tyrosine.
This amino acid is a precursor to neurotransmitters such as dopamine, and is therefore associated with antidepressant effects. It is also present in the process of melanin synthesis, which is a substance that gives color to the skin, eyes and hair.
Furthermore, tyrosine contributes to the functioning of the thyroid gland as it participates in the production of the hormones thyroxine (T4) and triiodothyronine (T3), which are responsible for regulating metabolism.
Health benefits
Tyrosine can be taken for several conditions and can offer health benefits such as:
- Improves mild and moderate depression and mood
- Improves memory in stressful situations, and improves the ability to perform tasks under pressure. However, some studies suggest that this effect may not happen in older adults
- Increases the number of white and red blood cells
- Helps in the treatment of some diseases, such as Parkinson's
- Improves performance in physical activity
It reduces the intensity of the body's response to a disease or a stressful situation, converting it to an essential amino acid, since in these cases its needs are increased.
Tyrosine supplementation could also help people who have phenylketonuria, which is a disease in which it is not possible to synthesize phenylalanine. Therefore, with this condition, it is not possible for tyrosine to be formed, as this amino acid is formed from phenylalanine. It can lead to a tyrosine deficiency in the body, however, studies relating the use of tyrosine supplements in people with phenylketonuria are not yet conclusive.
Main functions
Tyrosine is an amino acid responsible for several functions in the body. When it reaches the brain, it becomes a precursor for neurotransmitters, such as dopamine, norepinephrine and adrenaline, and can therefore be considered an essential part of the nervous system.
In addition, tyrosine also acts in the formation of thyroid hormones, catecholestrogens and melanin. It is also important for the formation of several proteins in the body, including enkephalins, which are considered the body's natural analgesics, as they are involved in pain regulation.
Foods with tyrosine
The following table indicates the main foods rich in tyrosine and the amount of this amino acid per serving:
In addition to these, other foods in which tyrosine can be found are mushrooms, green beans, potatoes, eggplant, beets, radishes, okra, turnips, chicory, asparagus, broccoli, cucumbers, parsley, red onions, spinach, tomatoes and cabbage.
How to take tyrosine supplements
There are two types of supplements, some with the free amino acid tyrosine, and others that have N-acetyl L-tyrosine, popularly known as NALT. The difference is that NALT is more soluble in water and is metabolized in the body more slowly. To obtain the same effect free tyrosine, it must be consumed in higher doses.
To improve mental performance in the face of a stressful situation or due to periods of sleep deprivation, for example, the recommendation is 100 to 200 mg/kg per day. However, studies are not conclusive regarding the intake of this amino acid for improving physical performance, you are advised to consume between 500 and 2000 mg one hour before the activity.
In any case, it is best to consult a doctor or registered dietitian before using a tyrosine supplement.
Contraindications to supplementation
The use of the supplement is contraindicated during pregnancy and breastfeeding, as there is not much information about it. It should also be avoided by people with hyperthyroidism or Graves' disease.
Furthermore, tyrosine can interact with thyroid medications, antidepressants and monoamine oxidase inhibitors, as it can cause an increase in blood pressure.
People with liver or kidney problems should only use tyrosine supplements as directed by a doctor.
Side effects
The most common side effects of using tyrosine supplements are headache, nausea, acidity, joint pain and feeling tired.
Furthermore, tyrosine can in blood pressure and, if consumed in large quantities, can have a laxative effect.
