L-tyrosine (L-tyrosine) is a conditionally replaceable amino acid. It is included in the list of twenty main human amino acids that are used for protein synthesis. In Greek, tyrosine means "cheese". Such a decoding may seem strange, but everything is quite logical, since this compound was first discovered back in 1846 in casein (milk cheese). Tyrosine is found in dairy products, meat, fish, legumes and grains. This compound is widely used in sports and medicine. It is used as an antidepressant, a fat-burning agent (not the main one), as well as a substance that can improve brain activity, increasing concentration and memory.

Mechanism of Tyrosine Formation There are two groups of amino acids. The first includes organic compounds of proteins that the body can produce on its own, they are called REPLACEABLE. The second group includes amino acids that cannot be synthesized inside the body without the right food, which contains these substances. These amino acids are of particular value to the human body and are called ESSENTIAL. Tyrosine belongs to the first group, because the body itself can produce tyrosine without its intake from outside. Although, this is a rather controversial point, since l-tyrosine is a derivative of such an alpha-amino acid as phenylalanine. Its absence makes the synthesis of tyrosine impossible, while the production of other amino acids is possible from glucose and ammonia. For this reason, it would be more correct to include the considered organic compound in the third subgroup of "conditionally replaceable amino acids".

The process of transition of Phenylalanine to tyrosine occurs in the liver. The main active ingredient is phenylalanine-4-hydroxylase. The transition process occurs due to the accumulation of excess surplus of phenylalanine and the need for its rapid utilization. All due to the fact that tyrosine can enter the body with protein-rich foods (meat, poultry, fish, nuts, milk, cottage cheese, and others). In 1934, the Norwegian doctor and biochemist I. A. Felling discovered the disease phenylketonuria, in which the conversion of phenylalanine to tyrosine is disrupted, which leads to serious damage to the central nervous system and causes dementia (oligophrenia). Phenylketonuria is treatable, for this it is important to keep a diet low in protein, excluding fish, meat and dairy products to prevent the formation of phenylalanine in the body. Tyrosine is of great importance in the synthesis of catecholamine hormones, including: dopamine, norepinephrine, adrenaline, thyroxine, triiodothyronine, L-dioxyphenylalanine and the color pigment melanin.

The mechanism of conversion of tyrosine to norepinephrine In the body, L-tyrosine is hydrolyzed by the action of the enzyme tyrosinase, the product of this process is the interstitial amino acid L-dioxyphenylalanine (DOPA). The next step in the transformation of tyrosine is the decarboxylation of L-dihydroxyphenylalanine under the influence of L-DOPA decarboxylase with the formation of the neurotransmitter dopamine. Dopamine is an important element of the "reward system", which is responsible for controlling human behavior. Dopamine acts as a serotonin antagonist, which allows you to increase a person's motivation and reduce fatigue at work. Next, dopamine reacts with dopamine beta-hydroxylase, which leads to the formation of NORADRENALIN.

Norepinephrine stops the conversion of tyrosine to dopamine, in this way the production of dopamine and norepinephrine is regulated. Norepinephrine is responsible for a positive perception of the world, quick decision making. Participates in the "fight or flight" system, increases muscle strength in the short term, reduces sensitivity to pain. Mental Focus and Tyrosine Many athletes who have been in the gym for a long time have probably heard about mental focus and its role in building quality muscle mass. It has been scientifically proven that during competitions or under the supervision of a coach (following some commands), a person can lift 5-10% more weight than during normal training. Almost the same positive effect on the increase in working weights has the right music for training. So, this is what I'm up to.

Many athletes use tyrosine-based supplements to elevate mood, focus, and prepare their body and mind for the upcoming workout. Research Research conducted in 2002 by Chinever. The subjects were cyclists, consuming 25 mg of the substance per 1 kg of body. The data obtained as a result of this experiment did not confirm the positive effects of tyrosine. Subsequently, the substance "bupropion" was used to raise the concentration of dopamine. It was noted that "bupropion" increased performance in warm conditions (30°C), in relation to data at 18°C. L-Tyrosine increased endurance at high temperatures (30°C). Another study released in 2014 showed improvements in creative thinking. Volunteers who took fruit juice supplemented with tyrosine showed greater intellectual ability compared to the non-tyrosine group.

In one study, children diagnosed with ADHD (attention deficit hyperactivity disorder) were given supplements of tyrosine and 5-HTP at dosages of 1,500 mg, and 150 mg of 5-hydroxytryptophan. A decrease in ADHD symptoms was found. Although, other nutrients were also used in this study, namely: 1 g vitamin C 0.22 g calcium citrate 0.075 g vitamin B6 0.4 mg folic acid 0.50 mg L-lysine 2.5 - 4.5 g L-cysteine ​​While it is undeniable that tyrosine has an effect on increasing attention and concentration in children, the fact that other supplements were also involved in the experiment casts doubt on the effectiveness of using this amino acid to combat such attention disorders. In one study, L-tyrosine at 150mg/kg bw was found to attenuate the process of cognitive decline that is associated with sleep disturbance in humans. It follows from this that the supplement improves cognitive performance in sleep deprivation without a significant impact on sleep function itself. Lack of tyrosine in the body Insufficient tyrosine production in humans can cause a number of negative factors and disruption of some processes occurring in the body. Symptoms of tyrosine deficiency can be depression, lowering blood pressure, lethargy, drowsiness, rapid weight gain. A lack of tyrosine can lead to a decrease in mental and physical activity, and in especially severe cases, to the development of HYPOTHYROISIS.

I must say that if a person has similar problems with the thyroid gland, you should not immediately run to the pharmacy or store sports nutrition for tyrosine. The fact is that this additive can only aggravate the situation, despite the fact that the problem arose due to the lack of this substance. An increase in the adrenal hormones, epinephrine and noradrenaline, suppresses thyroid function, resulting in many side effects. If a person has problems with the thyroid gland, it is necessary first of all to consult a medical specialist. Functions and actions of tyrosine Tyrosine performs a wide variety of functions in the human body, namely: Controls the management of circadian rhythms through the production of melatonin. Promotes increased attention and concentration. Responsible for the normalization of metabolism. Helps suppress hunger. Stimulates fat burning processes in the body. It has a direct effect on the functioning of the endocrine glands. Helps reduce fatigue from physical and mental activity. Increases stress resistance and normalizes mood. Reduces allergic manifestations. The action of tyrosine at the present time is widely used in many fields of medicine. It is used as a fight against obesity in humans caused by stress. Treatment of nervous disorders and depression, by means of normalizing thyroid hormones and influencing dopamine. Tyrosine, together with tryptophan, has been successfully used to combat Parkinson's disease. There is a significant reduction in allergic reactions with the use of tyrosine. Tyrosine is used to normalize the production of thyroid hormones, insufficient production of which can lead to hyperthyroidism. In addition, tyrosine is used in the treatment of diseases such as some forms of tuberculosis, in particular tuberculous meningitis, poliomyelitis, hyperthyroidism. Effects of tyrosine on fat burning In addition to the fact that tyrosine increases endurance, it speeds up metabolism and has a beneficial effect on lipolysis (the breakdown of fats into fatty acids, fat burning). Due to the effect on the production of the hormones thyroxine and triiodteronine, which have a powerful fat-burning effect, the action of tyrosine is enhanced.

The feeling of hunger is also moderately suppressed, this property helps people in many ways, dieters, significantly reduce the risk of relapse. The increase in stress resistance due to the intake of tyrosine has a positive effect, both on people who are already on a diet, and on people who have stress, provoked weight gain. Release form Today, the market offers a large selection of triazine preparations, such as sports supplements, dietary supplements and pharmaceutical drugs. The most popular drugs on the market are in the form of L-Tyrosine, from Now Foods, Universal Nutrition, VPX Sports and others. Also on the market is a modified form of L-Tyrosine - N-acetyl-tyrosine. It keeps the concentration of the substance in the body longer, has improved digestibility and bioavailability than its "L" counterparts. Tyrosine from sports nutrition suppliers is often cheaper than pharmacy analogues, but there is a risk of falling into an unscrupulous manufacturer whose declared composition of the components contradicts the actual content of the claimed substance. Dosage (Daily Value) and Method of Administration The daily requirement for tyrosine in an adult is 25 mg/kg of body weight, depending on energy expenditure. Considering that an ordinary person consumes about half of the substance from the daily norm. That is, if you decide to try taking this amino acid to improve memory or fight stress, the optimal dosage of the supplement should be no more than 12.5 mg / kg of the total mass. The dosage of the agent used can also be prescribed based on the goals pursued. The use of tyrosine as an antidepressant is dosed from 0.5 to 1 g. three times per day. With insomnia, the dosage can be up to 1500 mg / day,