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Leucine. Daily norm

    Proteins – essential elements human body, they take part in the synthesis of hormones and enzymes necessary for the implementation huge number biochemical reactions. Complex protein molecules are built from various. Leucine is one of the most important compounds in this group. It belongs to the essential amino acids, which the body cannot synthesize on its own, but only receives from the outside.

    Leucine is used in sports nutrition, medicine, agriculture. IN Food Industry it is known as additive E641 L-leucine, and is used to modify the taste and smell of foods.

    Amino acid scientific research

    Leucine was isolated and its structural formula was described by the chemist Henri Braconneau in 1820. At the beginning of the 20th century, Hermann Emil Fischer was able to artificially synthesize this compound. In 2007, the journal Diabetes published the results of a scientific study of the functions and properties of leucine. You can view the results and conclusions of scientists by following the link (information is presented on English language).

    The experiment was carried out on laboratory mice. The animals were divided into two groups. In the first of them, the rodents received regular food, while the diet of the second included an excess of fatty foods. In turn, each of the groups was divided into subgroups: in one of them, the animals were given 55 mg of leucine daily, and in the second, the mice did not receive any additional compounds besides the proposed diet.

    Based on the results of 15 weeks, it turned out that the animals that were fed fatty foods, gained weight. However, those who additionally received leucine gained 25% less than those who did not receive the amino acid in their diet.

    In addition, analyzes showed that animals taking leucine consumed larger amounts of oxygen compared to others. This means that their metabolic processes went faster, and more energy and calories were burned. This fact showed scientists that the amino acid slows down the process of fat accumulation.

    Laboratory research muscle fibers and adipocytes of white adipose tissue made it possible to establish that additional intake of leucine into the body stimulates the production of the uncoupling protein gene. It promotes more intense fat burning at the cellular level.

    In 2009, scientists from the University of Pennsylvania repeated the experiment of their colleagues. The results of this study can be found here (the information is also presented in English). The conclusions made before were confirmed. It was also found that taking smaller amounts of the amino acid had no effect on mice.

    Biological role of leucine

    Leucine plays important role in many processes. It performs the following functions:

    • slowing down processes in muscles;
    • accelerating the formation of protein molecules, which promotes growth muscle mass;
    • decreased blood sugar levels;
    • ensuring the balance of nitrogen and nitrogenous compounds necessary for metabolism;
    • preventing excess synthesis, which helps reduce fatigue and accelerate recovery after exercise.

    A normal level of leucine in the blood strengthens the immune system, helps wound healing, more rapid recovery after injuries. The body uses it as a source of energy.

    Application in sports

    For intense physical activity The body requires a large amount of substances to build muscle fibers and extract energy. In sports, especially in strength sports, for example, bodybuilding, powerlifting, leucine intake is common.

    It is necessary to reduce the intensity of catabolism and accelerate anabolic processes. Typically the amino acid is taken in the form sports supplements containing the complex. It contains three essential amino acids - leucine, isoleucine and valine.

    In such dietary supplements, the ratio of components is usually 2:1:1 (leucine, its isomer and valine, respectively); some manufacturers increase the content of the former by two or even four times.

    This amino acid is used by athletes both to build muscle mass and to lose weight. In addition, taking leucine helps increase energy potential, which is necessary for improving athletic performance.

    Application in medicine

    Preparations containing leucine are also used for therapeutic purposes. They are prescribed for severe liver diseases, dystrophy, polio, neuritis, anemia, and some mental health disorders.

    As a rule, taking this compound is supplemented with medications containing other amino acids to enhance the therapeutic effect.

    The benefits of leucine for the body include the following effects:

    • normalization of hepatocyte function;
    • strengthening immunity;
    • reducing the risk of obesity;
    • supporting proper muscle development;
    • accelerating recovery after physical activity, increasing performance;
    • beneficial effect on skin condition.

    The amino acid is used to restore patients suffering from dystrophy; it is prescribed after long fasting. It is also used in the treatment of cancer patients and patients with liver cirrhosis. Used to speed up recovery after injuries, surgical interventions, as well as in anti-aging programs.

    Daily requirement

    The need for an adult is 4-6 g of leucine per day. Athletes require slightly more of this compound.

  1. If the goal is to build muscle mass, then it is recommended to take 5-10 grams during and after training. This regimen will allow you to maintain a sufficient level of leucine in the blood during intense exercise, which will ensure stable formation of muscle fibers.
  2. If the athlete’s goal is to lose weight and cut weight, then supplements containing leucine should be taken 2-4 times a day, in an amount of about 15 grams. You need to drink the supplement during and after training, as well as 1-2 more times a day, between meals. This scheme will help stimulate metabolism, intensively lose fat, while maintaining muscle mass, suppressing catabolic processes.

Exceeding the norm can lead to an excess of leucine in the body, causing harm to health. It is advisable to consult a physician before using medications or dietary supplements containing this amino acid. Athletes can rely on an experienced professional trainer to select the appropriate dosage.

Consequences of deficiency and excess of leucine in the body

Leucine is an essential amino acid, and it is very important to get enough of this compound from outside. Its lack in the body leads to the fact that the nitrogen balance becomes negative and the course of metabolic processes is disrupted.

Leucine deficiency causes growth retardation in children due to insufficient production of growth hormone. Also, a lack of this amino acid provokes the development of hypoglycemia. Begin pathological changes in the kidneys, thyroid gland.

Everything is good in moderation, and excess leucine can also lead to various problems. Excessive intake of this amino acid contributes to the development of the following pathological conditions:

  • neurological disorders;
  • subdepressive states;
  • headache;
  • hypoglycemia;
  • development of negative immunological reactions;
  • atrophy of muscle tissue.

Food Sources of Leucine

The body can only obtain this amino acid from food or special supplements and medications. It is very important to ensure an adequate supply of this compound.

One of the leucine supplements

To do this, you should consume the following products.

Greetings, regular guest of my sports page. I want to touch on a topic that vitally concerns all bodybuilders - sports nutrition. Today we will talk about leucine, an amino acid found in sports supplements and protein shakes. In bodybuilding, leucine is rightfully considered an indispensable component of sports nutrition, because it is for an athlete’s muscles like gasoline for a car: if you don’t fill it up, you won’t go far. Well, now everything is in order...

What is leucine

Interesting articles about chemical additives and their action:

Leucine is an essential branched chain amino acid that our body cannot produce on its own. Due to the fact that she has a number useful properties, it is included in many products for athletes.

So that my dear readers can understand why leucine is so important for a bodybuilder, I will tell you about its properties. Strength athletes in sports such as bodybuilding, arm wrestling and powerlifting simply cannot imagine their path to success without this substance.

Because leucine is in human body- This:

  • maintaining nitrogen balance;
  • blood glucose control;
  • increasing the body's performance;
  • building material for muscle fibers;
  • preventing muscle breakdown during physical activity;
  • support of water metabolism in the body, since when protein in the blood decreases, edema appears;
  • participation in protein synthesis;
  • acceleration of metabolism, thereby promoting fat burning;
  • promotion protective properties body;
  • promoting rapid recovery of strength after training.

Of all the amino acids in the body, leucine accounts for about 8%. Its miraculous properties are also recognized official medicine, which applies it for a number serious illnesses(anemia, toxicosis, muscular dystrophy and damage to the central nervous system).

An important property of leucine is the stimulation of collagen synthesis, due to which articular cartilage not only is not destroyed, but is also able to recover.

The instructions for use do not indicate exactly when it should be taken, so you should assume that this can be done at any time of the day. Bodybuilders recommend taking it either before or immediately after a workout.

Some professional athletes take 3-5 grams of leucine at a time during training. It is not recommended to take leucine in its pure form; it is effective in combination with valine and isoleucine in a ratio of 2:1:1. In this form and in these proportions, it is equivalent to meat and dairy products.


Let's now see how leucine should be taken depending on the purpose:

  • If you are trying to gain weight, then you should take products containing this substance 3 times - before training, during and immediately after. Before taking the amino acid, you should thoroughly stir it in water and add sugar. This mixture will give you strength and energy for a long and productive workout without feeling tired.
  • If you want to achieve muscle drying, then do not add sugar to the cocktail, and take it additionally between meals. With this regimen, it will be possible to suppress the processes of muscle cell breakdown, this will relieve you of the unpleasant feeling of hunger and will promote muscle growth.

Some sports nutrition experts believe that there is no such thing as too much leucine. However, you can give an example of calculating the dosage for a person. So, an athlete weighing 50 kg needs to take 1800 mg of leucine at one time.


Thus, 1 kilogram of weight of an adult athletic person requires 36 grams of this amino acid. Some strength athletes take 5-10 grams of leucine at a time between meals, if there is a need to lose weight, for example.

Positive point of the reception this tool is the absence of an overdose, regardless of the amount taken, and side effects.

Application in medicine

As already mentioned, even official medicine recognizes and uses leucine in the fight against serious ailments, such as liver dysfunction (hepatitis and cirrhosis), reduced body weight (cachexia, dystrophy), metabolic disorders and the prevention of immunodeficiencies. Preparations containing this amino acid can be purchased in pharmacies without a prescription and in sports nutrition stores.


If you want to create a diet of foods rich in leucine, then you should pay attention to animal and poultry meat, fish, eggs, black and red caviar, dairy products, as well as cereals, nuts and legumes. To effectively absorb this amino acid, you should consume it with foods rich in B vitamins (B5 and B6). A sufficient amount of leucine is found in protein shakes.

Let me summarize

Leucine belongs to the group of essential amino acids that are part of all proteins in a living organism. It can be called one of the most important, since at the molecular level it is involved in the process of protein formation, which means that it is not only in the group called essential acids, but not replaceable for normal operation the entire human body. It is one of three amino acids (leucine, isoleucine, valine) that are involved in the construction and regenerative processes of cells. It was discovered by two scientists Gerard and Laurent. The amino acid is white crystalline substance, which is poorly soluble in water, without a characteristic taste or odor. There are a number of foods that are especially rich in leucine - nuts, meat, fish, eggs, dairy products. This amino acid is also synthesized chemically and can be purchased in biological form. active additive(capsules, tablets, liquid). For diseases, leucine-based drugs are used.

Pharmacological properties

Leucine plays key role in the construction of all muscle tissue, participates in the process of metabolism and energy production, has the ability to lower blood sugar levels, but increase immunity. Responsible for growth hormone, so it is important to note that leucine is especially important for a child’s growing body; its deficiency can lead to stunted growth. Leucine is also a basic substance in the formation of anabolic hormones, which are responsible for male sexual function and muscle mass (athletic physique). It is impossible not to note the importance of leucine for the central nervous system, since the amino acid has a stimulating effect.

Indications for use

IN Lately leucine is well-known due to the popularity of this amino acid among bodybuilders, athletes and those who like to visit fitness clubs. Therefore, firstly, it is recommended for overweight people, or people who want to build muscle mass. Leucine helps athletes recover after heavy physical exertion, as one of the most important tasks essential amino acid – regenerate and restore muscle tissue. Liver diseases, anemia, high cholesterol, immunodeficiency, long-term therapy with antibiotics, chemotherapy for oncological diseases- This is a number of direct indications when the amino acid leucine is used.

Contraindications

Pregnancy, lactation, childhood up to 18 years old, increased sensitivity to leucine.

Side effects

Skin rashes accompanied by itching.

For elderly people and patients with type 2 diabetes. For example, Scientific research it seems that taking protein with more high content leucine is the most effective, and 1 gram of leucine without other amino acids is sufficient to stimulate the synthesis of muscle protein. It is also known that the maximum possible benefits are obtained by taking 20 grams of protein at a time, but even a quarter of this dose can give maxi-small me-ta-bo-li-chess advantages with additional lei-qi-na, which indicates that that leucine is a key amino acid that stimulates muscle protein synthesis.

But it should be understood that amino acids are not only found in the form of dietary supplements. They can also be obtained from natural sources food, such as meat. And there is absolutely no need to focus on sports nutrition if there is no possibility and/or appropriate goals. Strength training in itself is a sufficiently precise method for the synthesis of skeletal muscle protein, and if the athlete builds it correctly training plan , nutrition and the process of restoration, then this is not quite enough to show the bitsukha to the girls on the beach. On the other hand, if there is an opportunity and desire, then sports nutrition, and leucine in particular, can facilitate and speed up this process.

Leucine for mass gain

As we have already shown above, strength training is a catalyst for muscle growth, which is realized through accelerated muscle protein synthesis. Research shows that the peak synthesis of protein structures occurs 3 hours after training, and increased speed their synthesis lasts 48 hours. Increased consumption of protein in any form during this period contributes to the growth of skeletal muscles, , , . But it is also well known that the process of anabolic lysis of protein structures is ensured by essential amino acids, and the main catalyst for this process is leucine. At the same time, training starts not only the synthesis, but also the destruction of skeletal muscle proteins, that’s why taking amino-no-kis -Lot after training is important not so much because they contribute to anabolism, but because they prevent catabolism.

Leucine and the heart

Chronic heart failure is often the result of many heart-related diseases that cause hypertrophy of the heart muscle. The changes that occur in the tissues of the heart are associated with the accumulation of incorrectly folded protein and apo-pto-cells, leading to a deterioration in the quality of myocardial tissue. Taking leu-qi can help prevent this, but it is much more effective when taken together with cardio exercises. And it’s best for you to heart training special training sessions that will last for several hours in order to properly stretch the ventricle of the left atria. It is especially important to do this for those who are gaining excess muscle mass or lead a sedentary lifestyle.

Leucine and age

With age, sarcopenia inevitably occurs, which is the main factor in reducing the quality of life and physical disability. This process is due to the de-gra-da-qi-ey of skeletal muscle proteins. And this is a reason to play strong sports, if only for the sake of health. But, unfortunately, with age, the anabolic response of muscles to training decreases, and this is where leucine supplements or its increased consumption from food can come to the rescue. ta-mi pi-ta-niya, . In particular, this is due to the ability of leucine to independently act on the mTOR complex, as well as other gene transcription pathways, , , . In addition, an important role in this process is played by the ability of leu-qi to control the metabolism of insulin, which allows one to achieve a beam -sensitivity of skeletal muscle cells to glucose.

Conclusion: Scientific research confirms the effectiveness of taking leucine for sports purposes, as well as as a means to prevent heart disease and slow down the process of heart disease.

Sources

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Leucine is actively used in dietary supplements for athletes and bodybuilders, as well as in medicines. This substance helps build muscle and burn fat, which has a positive effect on your figure. With proper nutrition, its amount is most often sufficient for ordinary person. Let's take a closer look at the importance of this amino acid for the body.

Characteristics and influence

Leucine is one of the essential amino acids for the human body; it is part of proteins and is supplied only with food. This aliphatic amino acid in living cells it is found in the form of an L-optical isomer and has the formula HO2CCH(NH2)CH2CH(CH3)2.

In its pure form it is a colorless powder, poorly soluble in water, but highly soluble in alkaline media and acids.

Is the most important among three existing branched chain amino acids (there is also isoleucine and valine). They are also called hydrophobic. What makes it especially popular is its ability to build muscle.

Leucine Processing produced by the liver, but mostly by adipose and muscle tissue. This essential amino acid stimulates protein synthesis, and its intake can slow down muscle degradation, is a catalyst for muscle growth and a kind of insurance against muscle damage.

In addition, leucine provides more energy to the body than glucose and promotes its absorption by the liver. Among all amino acids, it most strongly activates rapamycin kinase, which regulates cell growth in animals.

Did you know? The first to obtain it was the French chemist and pharmacist Henri Braconneau from animal muscles and hair in 1820. Now quality product synthesized from plant materials (soy) or milk proteins. Until 2010, L-leucine was food additive E 641 to enhance the taste and smell of products.

The bioavailability of leucine is more than 96%. The pancreas, liver, spleen, and kidneys participate in its absorption and processing. It is the kidneys that remove its excess.

Main functions and benefits

Leucine does important functions in organism:

  • promotes insulin production;
  • participates in metabolic processes proteins and carbohydrates;
  • important for growth and normal development muscles;
  • protects muscle tissue from decay and injury, heals wounds;
  • energetically effective for body cells;
  • maintains serotonin levels;
  • takes part in the synthesis of protein and hemoglobin.

Its benefits for the human body:

  • normalizes blood sugar;
  • strengthens the immune system;
  • promotes proper development muscles;
  • normalizes liver function;
  • reduces the risk of obesity;
  • reduces fatigue and increases performance;
  • has a positive effect on the condition of the skin, reduces the appearance of cellulite and is used in anti-aging programs.

Leucine is used in medicine. It improves clinical condition patients with fasting, oncology, liver diseases, after surgery, injuries, sepsis.

It is prescribed to cancer patients before and after operations, chemotherapy and other specific treatment to correct amino acid imbalance.
Used in the treatment of anemia, muscle dystrophy, diabetes, Menkes syndrome, polio, renal failure, liver cirrhosis and other liver diseases.

Products - sources of leucine

A large number of Leucine is found in animal products, but vegetarians can also get it from.

Did you know? Alcohol interferes with the absorption of leucine.
  • concentrate soy protein- 4.917 g;
  • egg powder - 3.77 g;
  • Parmesan cheese - 3.45 g;
  • red caviar - 3.06 g;
  • soybeans - 2.75 g;
  • milk powder - 2.445 g;
  • cheese “Poshekhonsky” - 1.96 g;
  • - 1.92 g;
  • Cheddar cheese, skim cheese- 1.85 g;
  • Swiss cheese - 1.84 g;
  • peanuts - 1.763 g;
  • beans - 1.74 g;
  • pink salmon - 1.71 g;
  • peas - 1.65 g;
  • sea ​​bass, herring, mackerel - 1.6 g;
  • turkey meat - 1.59 g;
  • pistachios - 1.542 g;
  • millet - 1.53 g;
  • mackerel - 1.54 g;
  • Roquefort cheese - 1.52 g;
  • beef - 1.48 g;
  • - 1.47 g;
  • chicken - 1.41 g;
  • pike perch, pike - 1.4 g;
  • sunflower seeds - 1.343 g;
  • - 1.338 g;
  • cod, pollock - 1.3 g;
  • almonds - 1.28 g;
  • - 1.17 g;
  • lamb - 1.12 g;
  • corn grits - 1.1 g;
  • chicken egg - 1.08 g;
  • lean pork - 1.07 g;
  • hazelnuts - 1.05 g.

 So those who want to build muscle or children (for growth) need to include cheeses, nuts (especially peanuts), legumes, seafood and meat in their diet.

In vegetables and fruits, mushrooms, the proportion of leucine is very small.

Daily requirement and norm

For a healthy adult, the daily requirement of leucine will be 4-6 grams. To cover this need, a person only needs to eat 3 eggs, 200 grams of beef, 100 grams of cottage cheese, and drink a glass of milk or kefir every day.

Important! At high cholesterol It is not recommended to consume dairy products with a fat content higher than 5%, fatty and fried meat (especially red). Cholesterol content in yolks chicken eggs also quite high. It is better to pay attention to nuts (peanuts), seeds, legumes and some types of cereals (millet and corn), and seafood.


 For bodybuilders and athletes, this norm is twice as much.

For a manual worker and with frequent power loads, it will also be higher.

The daily requirement for the growing body of children is calculated from the norm of this amino acid 0.15 grams per kilogram of the child’s weight.

This is important to consider when planning his diet.

About excess and deficiency

Leucine promotes weight loss and the formation of a beautiful body, but you shouldn’t get too carried away with it.

Even such an important and indispensable amino acid for a living organism is good and healthy when the norms are followed when consuming it.

Excess

Excessive consumption of leucine leads to the following consequences:

  • nervous disorders (depression, severe drowsiness, headache);
  • liver dysfunction;
  • amyotrophy;
  • hypoglycemia ( low level blood glucose);
  • allergic reactions.

Important! People taking medications with leucine or engaging in physical activity should be aware of the signs of hypoglycemia: muscle tremors, high pressure and arrhythmia, excited nervous reactions, inappropriate behavior, migraine and dizziness, drowsiness, impaired coordination and disorientation, weakness and others.

a lack of

Leucine deficiency especially dangerous for the growing child’s body, since it slows down its growth and physical development. That is why it is so important for children to organize proper nutrition. Its deficiency in adults can lead to obesity and various mental illnesses.

In addition, this can lead to dysfunction of the liver, kidneys, and thyroid gland.

A lack of this amino acid can also lead to hypoglycemia and associated negative effects.

Interaction with other substances

Leucine has not had any negative interactions with other substances. Interacting with glucose, it reduces its level in the blood and affects the activity of the pancreas.
Together with resveratrol, it leads to a reduction in body fat and weight. There is a hypothesis about its synergy with citrulline, which helps build muscle mass.

Role in sports

Since the need for leucine during physical activity greatly increases, this amino acid is often used in dietary supplements for athletes and is actively used in bodybuilding and arm wrestling.

Manufacturers of dietary supplements for athletes initially produced them with the following proportions of leucine, isoleucine, valine - 2:1:1.

But now there is evidence that it is much more rational to use only leucine, since it most strongly affects rapamycin kinase and has the highest anabolic effect.
This amino acid has a positive effect on the quality of muscle tissue and promotes healing when sports injuries, and its deficiency causes high fatigue. In addition, it promotes fat burning.

A person who is engaged in active exercise and has set himself the goal of building more muscle does not always manage to take this amino acid in sufficient quantity from food.

Did you know? It is best to take leucine before training.

About contraindications and precautions

Leucine is contraindicated in hereditary diseases associated with disruption of its metabolism:

  • leucinosis (a urine disease that smells like maple syrup);
  • isovaleratacidemia (disease with the smell of sweaty feet).

 With these rare genetic disorders, foods containing hydrophobic amino acids are completely excluded from the diet. Typically, such diseases are detected in the first weeks of life.

For patients in need of therapy with this substance, medications and doses are prescribed by a doctor.

An experienced trainer recommends preparations and doses with this amino acid to athletes. But it is advisable for them to consult a doctor and monitor their condition.
Normal human existence is impossible without leucine. Its deficiency can cause delayed physical development in children.

There is enough of it in food, but during high physical activity the norm of leucine can double, and athletes often take preparations with this essential amino acid.

An excess of this substance is harmful, so you should consult a doctor when taking it.