Amino acid L-lysine from a scientific point of view
Amino Acids and Proteins
L-lysine is a protein-forming amino acid. Proteins are an essential structural element of all tissues of the human body (and not just the muscles with which they are often associated).
They play an important role in the construction of many biologically active compounds, such as enzymes and hormones, which are of great importance for the normal functioning of the human body. Proteins are compounds with a very complex structure, the basis of which is formed by amino acids.
Amino Acids are divided into exogenous (or indispensable — which should always be in the human diet), conditionally exogenous (conditionally replaceable — necessary during the period of growth and development of children; in adults, not necessarily present in the diet) and endogenous (replaceable — which the human body itself is able to produce ).
The quality of the protein – its nutritional value – is determined by the content of exogenous and endogenous amino acids, their relative proportions and digestibility of the product. The best quality is possessed by a complete protein – one that contains all exogenous amino acids in such ratios that best meet the needs of the human body.
TO high-grade squirrels first of all, they include chicken egg protein and breast milk protein (they are reference), other milk proteins (for example, cow’s milk) and partially meat proteins. Partially incomplete proteins contain all the essential amino acids, but some of them are in insufficient quantities. An example of such a protein are cereal proteins (they are deficient in lysine).
The last group – defective proteins – does not contain any essential amino acids. For example, Zein (maize protein) is inferior.
As you can see, the basis for the separation of proteins into those that provide life and development (complete), only the maintenance of life (partially incomplete) and insufficient even to support life (inferior) are based on the content of essential amino acids in them that are not produced in humans and therefore must come from food. These amino acids (they are from 8 to 10 – depending on the person’s age) include L-lysine.
L-lysine as a limiting amino acid
L-lysine is a compound that is quite common in nature; however, due to its low content in cereal products, it is considered the most important limiting amino acid in this food group. A limiting amino acid is such an exogenous (i.e., irreplaceable) amino acid, which this protein contains least of all. Its amount is a factor limiting the use of other amino acids from this protein, which reduces its nutritional value.
In other words, this protein can be used by the body to the extent that the limiting amino acid allows – that is, the one that has the lowest content in the protein. To make full use of food proteins, products with a low content of this amino acid are combined with products that contain it in large quantities.
Therefore, grain products (for example, oats) are traditionally combined with dairy products, which are a good source of L-lysine, which as a result increases the protein value of the dish as a whole.
The amount of L-lysine in various grain products varies not only depending on the product itself (not much in oats, a lot in amaranth), but also on the growing season, and on the composition of fertilizers. Studies have shown that in winter barley, as well as with increased nitrogen content in the soil, the biomass contains much less than many amino acids, including L-lysine.
The amount of L-lysine in food products also depends on heat treatment. Its main sources in the diet: meat, fish, eggs, dairy products – are often exposed to high temperatures. Unfortunately, when frying or baking food products containing lysine (in particular, meat), most of it is destroyed, and as a result the prepared dish contains a small amount of lysine.
This is due to the fact that as a result of exposure to high temperature, L-lysine enters into so-called Maillard reactions – which are responsible for the formation of the smell, taste and color of the product (crisp bread crust, crispy fried eggs, the delicious smell of fried meat) – and becomes indigestible organism. As a result, it cannot be used to synthesize proteins in the human body.
The role of L-lysine in the body
L-lysine in the human body performs a number of important functions. It is necessary for the growth and development of cartilage tissue, the synthesis of nucleotides forming DNA, as well as for lactation. It is involved in tissue repair, the production of enzymes, hormones and antibodies, and also affects fat metabolism.
In other words, L-lysine ensures proper bone structure and the corresponding milk composition during breastfeeding. It also has a positive effect on immunity and makes fat burning possible. Its influence on all these processes is not, however, direct – it performs most of its functions as part of biologically active compounds.
Due to the fact that L-lysine is involved in many processes in the human body, its deficiency can manifest itself nonspecific – for example, in the form of anemia, hair loss, or irritability and difficulties with concentration. A delay in growth, muscle atrophy, impaired protein synthesis and softening of bones can also be a consequence of a lack of L-lysine in the diet.
L-lysine and collagen
L-lysine is mainly associated with the production of collagen, and collagen – with the strength of the skin. But collagen is not only skin and anti-wrinkle. Collagen is a protein that forms the extracellular matrix, that is, a structure that binds cells together and ensures the integrity of organs.
Collagen is not a homogeneous protein. Currently, there are 29 types of collagen, encoded by different genes, which differ in structure, function, content in tissues and in the body as a whole. Collagens form, in particular, the structure of the skin, cartilage, tendons, bone matrix, are responsible for the elasticity of the arteries.
To build normal collagen fibers, two exogenous components are needed (which the body cannot produce on its own): L-lysine and vitamin C. In order for lysine to form collagen fibers, it must undergo a series of transformations with the participation of the appropriate enzymes. Vitamin C provides these enzymes. Both of these substances are thus necessary for the production of collagen, and if either of them is lacking, the formation of collagen can be impaired.
Since collagen forms the structure of the skin, bones, cartilage and arteries, L-lysine, which is one of the main components of collagen, affects both the bone and joint system, the quality and elasticity of the skin, and the cardiovascular system. Collagen fibers (and, respectively, L-lysine) are also involved in wound healing and tissue regeneration.
In addition, studies show that the content of lysine has an inhibitory effect on certain parameters of angiogenesis – the formation of new blood vessels. In general, this process is positive, however, excessive angiogenesis is observed in tumors and in atherosclerosis.
L-lysine affects the bone and articular structures, not only through the construction of collagens. This amino acid helps the body to absorb calcium, thereby ensuring the mineralization of the skeleton, which is especially important during the growth period, as well as in pre- and postmenopause.
L-lysine and L-carnitine
The effect of L-lysine on the human body can manifest itself not only on the osteo-articular system, the structure of the skin and arteries. L-lysine makes it possible to burn adipose tissue, which is important for losing weight. This is because L-lysine is the raw material for production in the human body L-carnitine – compounds responsible for the process of burning fat.
Burning adipose tissue occurs due to the so-called beta-oxidation process, which occurs in cellular mitochondria. In order for this process to go on continuously, a transport is needed that would deliver free fatty acids to the “stove”. This transporter is L-carnitine. So without L-carnitine there is no fat burning, and without L-lysine there is no L-carnitine.
But L-carnitine is not only a fat burner. This compound has a universal effect: it is an antioxidant, helps remove excess iron, lead and cadmium, stabilizes cell membranes. In addition, recent studies have shown that L-carnitine and its natural derivative propionyl-L-carnitine have the ability to modulate the metabolism of cardiac muscle cells and can be used for the prevention and treatment of cardiovascular diseases.
But these are not all the positive effects of this compound in the body. L-carnitine also has an effect on the nervous system – it increases concentration and learning ability, improves reflexes, is an anti-depressant. In addition, L-carnitine also affects the reproductive system of men – increases sperm motility. The typical symptoms of its deficiency, especially with a vegetarian diet, are muscle weakness and symptoms of coronary insufficiency.
L-lysine and free radicals
L-lysine has antioxidant properties – not only indirectly, as a result of L-carnitine production, but also directly. Analysis of the composition of legume vegetable proteins showed that they have a high antioxidant potential. Studies have shown that this is due to the presence, among other substances, of lysine.
L-lysine and viral infections
In addition to all the listed properties of L-lysine, its effect on the immune system should be noted. Lysine not only prevents colds and eases the flu. First of all, it is important that a diet rich in lysine helps counteract a number of viral infections, in particular, herpes (Herpes simplex).
There is, however, one condition: a diet rich in L-lysine must also have a low content of another amino acid, arginine. While lysine inhibits the growth of the herpes virus, arginine, on the contrary, supports it.
L-lysine and galanine
A very interesting and important fact for the body is that L-lysine produces a compound called galanin.
Galanin is a substance that affects almost all processes in the body. In the hormonal system of the body, it is responsible for the secretion of certain pituitary hormones. In the nervous system is involved in the processes of memorization, as well as pain. In the digestive system affects the motility of the gastrointestinal tract and insulin secretion.
The fact that L-lysine is necessary for the production of galanin, perhaps, most clearly shows how important and indispensable this substance is for our health.
L-lysine and somatotropin
The effect of L-lysine on muscles and adipose tissue is also manifested by the fact that lysine can induce the pituitary gland to produce more growth hormone, somatotropin. A high level of this hormone increases muscle mass gain, leads to a decrease in reserves of subcutaneous fat and increases energy production. It also accelerates the regeneration of the entire body, especially after intense workouts.
L-lysine and colostrum protein
L-lysine is present in the human diet from the first moments of life – already in the womb from the food it takes and as a component of primary milk (colostrum). Colostrum is produced by mammalian mammary glands in the last days of pregnancy and in the first days after the baby is born. Food for them forms, first of all, the resistance of the newborn.
L-lysine is a component of casein and whey proteins, the main components of colostrum, and whey proteins have a higher biological activity than casein, and contain more L-lysine compared to them. The presence of L-lysine in colostrum – the very first food – indicates the importance of this amino acid for the development of a young organism.
This article is for informational purposes only; it does not replace a visit to a doctor or a specialist consultation.