The tyrosine is a key amino acid in the proper functioning of the central nervous system, notably through its role in the synthesis of neurotransmitters such as adrenalin, noradrenalin and dopamine.
In this article, discover all the benefits of tyrosine benefits of tyrosine, as well as its contraindications and its potential side effects.
What is tyrosine?
Unlike lysine and phenylalanine, which are essential amino acids, the "tyrosine or "L-tyrosine is a non-essential amino acid. In other words, our bodies are completely able to synthesize it from other amino acids.
The tyrosine plays several roles in our body. In particular, it is used to produce neurotransmitters such as dopamineand noradrenaline and adrenalinewhich are involved (among other things) in the mood and stress regulation.
The tyrosine naturally found in proteins of many foods, particularly meatsmeats fishfish products dairy productsthe nuts and seeds.
It is also available as as a dietary supplement. These are used for their beneficial effects on mental performanceperformance memory and concentrationas well as stress and anxiety.
What are the benefits of tyrosine?
Regular consumption of foods rich in tyrosine or taking a dietary supplement based on this amino acid can have many positive effects. health benefits:
Enhanced brain performance
Visit L-tyrosine is used by many peopleis used by many people, particularly students at exam time, to improve mental performance (concentration, attention, alertness, memory...).
A study published in Military Medicine showed that taking 100 mg/kg of L-tyrosine improved cognitive performance and memory. in soldiers exposed to high levels of stress [1].
Another study published in the Journal of Psychiatry and Neuroscience showed that taking L-tyrosine improved cognitive performance in people suffering from schizophrenia [2].
The tyrosine is converted in the body into catecholamines - neurotransmitters such as dopamineand noradrenaline and adrenaline - play an important role in the regulation of numerous mental functions, including moodmood motivation, attentionattention memory, learning and cognition.
Numerous scientific studies suggest that taking tyrosineintake, by increasing the availability of these neurotransmitters in the brain, may have beneficial effects on mental performance.
The tyrosine also has the ability to reduce the negative effects of stress on mental performance [2].
In fact stress is a factor that reduces availability of catecholamines in the brain, which can have a negative impact on the cognitive functions.
Reduces the effects of stress
Visit L-tyrosine can also help combat stress and its negative effects on the body.
A study published in the journal Brain Research showed that taking L-tyrosine reduced the response to stress in rats subjected to conditions of high environmental stress [3].
Thus, supplementation with tyrosine is particularly indicated for people subject to high levels of psychological stresse.g. during exam periods, intense professional activity, strong emotional pressure...
Tyrosine intake can also be useful in cases of overwork physical to stimulate dopamine synthesis and promote recovery.
Mood enhancement
Visit L-tyrosinea precursor for certain neuromodulators, is also used to improve mood.
In fact, by promoting the synthesis of dopamine and noradrenaline - neurotransmitters involved in vitality, dynamism and mood - tyrosine improves mood and fights certain disorders such as depression and melancholy.
Stimulates thyroid activity
The L-tyrosine is also involved in production of thyroid hormoneswhich are important for regulating metabolism.
A chronic tyrosine deficiency could promote the development of hypothyroidismparticularly in people predisposed to this condition, leading to symptoms such as a fatigue persistent fatiguefatigue concentration difficultiesconcentration constipationand lower heart rate...
What are the indications for tyrosine supplementation?
Visit dietary supplements based on L-tyrosine may be recommended in the following situations:
- Physical overwork
- Intense stress
- Low mood
- Stimulation of thyroid activity (medical advice required).
- Improves brain function (memory, attention...)
What are the recommended dosages for tyrosine?
Visit recommended doses of tyrosine vary according to the indication (objective of supplementation), body weight, age, physiological state, renal and hepatic function... Typically, tyrosine doses are in the range of between 500 mg and 2000 mg per day.
For situations of physical stress or periods of sleep deprivation, higher doses can be used, up to 150 mg/kg/day (i.e. 10 g for an adult weighing 70 kg).
To improve sports performancetyrosine is generally administered in doses between 500 to 2,000 mg 30 to 60 minutes before physical exertion.
What are the contraindications to L-tyrosine?
Visit L-tyrosine is generally considered to be safe when consumed in small quantities. normal doses. However, there are certain counter-indications and precautions to be taken into account:
- People suffering from thyroid gland pathology (particularly hyperthyroidism or "Graves' disease") should not take L-tyrosine without medical advice, as it may affect thyroid hormone production.
- People suffering from phenylketonuria (PKU) - a rare genetic disorder that prevents the body from properly metabolizing an amino acid called phenylalanine - should avoid taking L-tyrosine, as it is metabolized into phenylalanine.
- People taking monoamine oxidase inhibitors (MAOIs) for depression or other mood disorders should avoid taking L-tyrosine, as it may increase blood pressure.
- People suffering from Parkinson's disease or other dopaminergic disorders, as tyrosine may alter dopamine production or interact with prescribed drug treatments.
- People suffering fromhigh blood pressureas high doses of tyrosine can cause hypertensive spikes.
- The pregnant women or breastfeeding should avoid taking tyrosine supplements, as there is insufficient scientific data on their safety.
In all cases, it is advisable to consult your doctor before taking tyrosine supplements. any dietary supplementincluding L-tyrosine, to safeguard your health.
What are the side effects of tyrosine?
As mentioned above L-tyrosine is generally considered to be safe when consumed for normal doses.
In fact, studies that have tested very high doses of tyrosineup to 500 mg per kilogram of body weight per day (a far cry from the recommended dose, which should not exceed 150 mg/kg/day for up to 3 months), have shown that no detectable effect in humans.
However, some people may experience side effects when taking at L-tyrosine supplements.
Visit side effects most frequently observed after taking too much high intake from tyrosine are :
- Nausea
- Heartburn
- Joint pain
- Headaches
- Temporary fatigue
- Insomnia
- Increased blood pressure (at high doses)
- Increased blood sugar (high dose)
- mood changes
In very rare cases, L-tyrosine can cause more serious side effects, including heart palpitationsheart palpitations pain chest painand convulsions and hallucinations.
Fortunately, these effects rare and are more likely to occur in people who are taking high doses of L-tyrosine and who have underlying health problems.
It is therefore important to respect dosages indicated on the labels of tyrosine-based products.
Conclusion
These are the key points to remember about tyrosineits benefits and contraindications :
- L-tyrosine is an amino acid involved in the synthesis of certain neurotransmitters (dopamine, noradrenaline and adrenaline) and thyroid hormones.
- Tyrosine supplementation can help combat stress, boost cognitive and physical performance, improve mood and stimulate thyroid gland activity.
- Tyrosine supplementation is contraindicated in cases of: hyperthyroidism, phenylketonuria, ongoing MAOI antidepressant treatment, Parkinson's disease, high blood pressure, pregnancy or breast-feeding.
- Tyrosine's side effects are exceptional and are observed when doses taken are too high: nausea, heartburn, headaches, fatigue, insomnia, palpitations, convulsions...
Source :
- C. A. Salter, "Dietary Tyrosine as an Aid to Stress Resistance among Troops", Military Medicinevol. 154, no 3, p. 144-146, March 1989, doi: 10.1093/milmed/154.3.144.
- S. N. Young, "L-Tyrosine to alleviate the effects of stress?", Journal of Psychiatry and Neurosciencevol. 32, no 3, pp. 224-225, May 2007.
- H. Lehnert, D. K. Reinstein, B. W. Strowbridge, and R. J. Wurtman, "Neurochemical and behavioral consequences of acute, uncontrollable stress: Effects of dietary tyrosine." Brain Researchvol. 303, no 2, pp. 215-223, June 1984, doi: 10.1016/0006-8993(84)91207-1.
