Tyrosine is an amino acid, non-essential, synthesized by the body and found in certain foods. It is involved in the production of dopamine, norepinephrine, and thyroid hormones. The point with Dr. Camille Le Quéré nutritionist, the doctor in Paris.

Definition: What is tyrosine?

Tyrosine is an amino acid, a small molecule that synthesizes proteins. It is mainly found in poultry, almonds, bananas, avocados, sesame seeds... The body also produces it on its own, from another amino acid.

What is its role?

Tyrosine allows the production of dopamine and norepinephrine, substances that help the body adapt to stress in particular. It is also involved in the production of thyroid hormones. "Tyrosine also has secondary roles in the production of growth hormone, the production of melanin (skin pigmentation) and helps prevent the aging of cells, with an antioxidant action," says Camille Le Quéré, a nutritionist doctor in Paris.

What are the benefits of depression?

"Tyrosine has a precursor role to certain neurotransmitters that circulate information in the brain, including dopamine and norepinephrine," continues our specialist. These neurotransmitters act on the patient's psychic state. 'Dopamine is involved in the patient's vital momentum, dynamism, concentration, cognition. Norepinephrine is involved in mood, alertness, and vigilance mechanisms," observes Camille Le Quéré.

What are the benefits of the thyroid?

"Tyrosine is a precursor to the thyroid hormones, thyroxine, and triiodothyronine," notes the nutritionist. Lacking tyrosine can cause hypothyroidism and the symptoms that go with it: fatigue, difficulty concentrating, bradycardia...

How to dose tyrosine?

Tyrosine, a complex practice that takes place in a hospital setting, is very rarely dosed. "We do not dose the amino acid in routine. In my opinion, this dosage is only done in the context of research. Rather, it is based on a bundle of clinical arguments and other associated deficiencies such as deficiencies in iron, magnesium, zinc, vitamin B ... In view of which we identify a very clear risk of tyrosine deficiencies', explains Camille Le Quéré. "We will rather dose dopamine and norepinephrine in routine, a urine or blood test depending on the laboratory. It is not reimbursed and there are many false results due to the patient's diet. For the result to be revealing, the patient must have a diet low in tyrosine for a few days," says the doctor.

Tyrosine levels too low: what are the dangers?

Our expert observes several risks related to a tyrosine level that is too low:

Difficulty concentrating
Anxiety
Stress
Depression, loss of vital momentum
Hypothyroidism
Stunting (in extreme cases)
Premature cell aging
Fatigue
Skin fragility

Tyrosine levels too high: what are the dangers?

"The risks associated with too high a tyrosine level will depend on the patient's history," says Camille Le Quéré. Thus tyrosine can contribute to:

→ An increase in blood pressure and consequences on the cardiovascular system

→ A thyroid disorder causing hyperthyroidism (tachycardia, hypertension)

→ A disruption of metabolism and in particular blood sugar

In which foods to find tyrosine?

"Tyrosine is mainly found in protein-rich foods," says the nutritionist. It can be found in:

Milk
Egg
Meat
Fish
Nut
Cashew nuts
Almond
Lawyer
Mushroom
French bean
Potato
Eggplant
Beet
Radish
Asparagus
Parsley
Cucumber
Red onion
Spinach
Rye

When to supplement with tyrosine?

As part of an omnivorous diet, there is little risk of suffering from tyrosine deficiency. 'If there is a need for tyrosine supplementation, supplementation is contraindicated in the case of hyperthyroidism, if the patient is on antidepressants or for patients with Parkinson's disease. It is, therefore, necessary to be careful with these food supplements because there can be risks if the food supplements are poorly dosed, "warns Camille Le Quéré.

The specialist is not used to supplementing her patients with tyrosine. "I prescribe co-factors that will make it possible to synthesize tyrosine. That is to say that I supplement with vitamin B9 and magnesium in particular. Tyrosine supplementation can be considered as a last resort if the co-factors have not been effective enough," she continues. It does, however, identify a group of people who may need tyrosine supplementation, 'vegans or even vegetarians whose diets are low in protein.'

Tyrosine and Parkinson's disease

Tyrosine as a dietary supplement is strongly discouraged in people treated for dopaminergic disorders such as Parkinson's disease.

In addition, high-dose tyrosine can interact with the action of thyroid hormones, so in case of the pathology of the thyroid gland, it is advisable to consult a doctor before taking L-tyrosine.

Chemical properties

The crude formula of tyrosine is C9H11NO3, its molar mass is 181.1885 g/Mol. Tyrosine is an amino acid that is said to be non-essential for the human body. Indeed, we know how to synthesize it. However, it can be produced in insufficient quantities, hence the need to provide enough via food.

Tyrosine is characterized by its phenol group, whose hydroxyl is acidic. This amino acid is synthesized from phenylalanine. It has a very important role since it participates in the synthesis of many essential substances: dopamine, norepinephrine, adrenaline, etc. In addition, it is a precursor of thyroid hormones and melanin.

Historical

History of the nutrient

An amino acid with many roles in the body, tyrosine was also for a long time a molecule of choice for the treatment of certain conditions. Indeed, several patents have been obtained for the use of tyrosine in a therapeutic setting and in particular to treat depression, Parkinson's disease, or shock states.

Even today, the combination of DOPA and tyrosine is used to treat certain attention disorders such as hyperactivity.