Amino acids are a kind of compounds with special significance. Because many of them are the basic units of protein, which are closely related to life activities and are essential substances for human body, and some of them are directly used as medicine.
α -amino acid is the basic unit of protein. Protein can be gradually hydrolyzed into relatively simple molecules under the action of acid, alkali or enzyme, and the final products are various α -amino acids. The hydrolysis process can be expressed as follows:
Protein → moonlight → peptone → polypeptide → dipeptide → α-amino acid.
There are more than 20 kinds of α -amino acids * * * obtained by hydrolysis of protein, and the kinds and quantities of amino acids contained in various protein are different. Some amino acids cannot be synthesized in the human body and can only be supplied by food. These amino acids are called essential amino acids.
An organic acid containing amino groups; the basic unit of protein. Colorless crystal, high melting point (above 200℃), easily soluble in water, with amphoteric ionization characteristics, and sensitive to the color reaction with ninhydrin reagent. Glycine with the simplest structure was found in the protein hydrolysate of 1820. By 1940, there are about 20 kinds of amino acids in nature. They are necessary for human or animal to synthesize protein, and most of them are L-type α-amino acids. According to the number of amino groups and carboxyl groups contained in amino acid molecules, amino acids are divided into neutral amino acids (glycine, alanine, leucine, isoleucine, valine, cystine, cysteine, methionine, threonine, serine, phenylalanine, tyrosine, tryptophan, proline and hydroxyproline, etc. ), which contains only one amino group and one carboxyl group. Acidic amino acids (glutamic acid, aspartic acid), which contain one amino group and two carboxyl groups in the molecule; Basic amino acids (lysine and arginine) contain diaminocarboxyl groups in their molecules; Histidine has a nitrogen ring, which is weakly alkaline and also belongs to basic amino acids. Amino acids can be prepared from protein by hydrolysis or chemical synthesis. Since 1960s, microbial fermentation has been widely used in industry. For example, monosodium glutamate plants have generally turned to fermentation to produce glutamic acid. In recent years, petroleum hydrocarbons and other chemical products have been used as raw materials for amino acid fermentation.
The amino acids that make up protein have certain nutritional value. The amino acid mixture prepared in a proper proportion can be directly injected into human blood to supplement nutrition and partially replace plasma, which can enhance the disease resistance and promote the rehabilitation of patients with trauma, burns and surgery. Histidine, arginine, aspartic acid, glutamic acid and sulfur-containing amino acids have certain curative effects on liver diseases (such as infiltrative hepatitis). Cysteine can also resist radiation and treat heart failure. All kinds of essential amino acids have health care and nutritional functions to maintain the normal development of human beings and animals. If lysine is added to food, its nutritional value can be improved. Some people abroad use amino acids to make artificial fibers, artificial leather and plastics. Glycine is used to prevent rubber from aging. Tryptophan and histidine are used as antioxidants in oils and fats. Using amino acids as supplementary feed for poultry and livestock can improve their wool and meat quality.
Amino acids and human health
Amino acids are the most basic substances that constitute the protein of organisms, and are related to life activities. They are the basic units of protein molecules in organisms and are closely related to the life activities of organisms. It has a special physiological function in antibodies and is one of the indispensable nutrients in organisms.
First, the basic substance that constitutes the human body is the material basis of life.
1. constitutes one of the most basic substances in the human body.
Protein, lipids, carbohydrates, inorganic salts, vitamins, water and dietary fiber are the most basic substances that constitute the human body.
As the basic unit of protein molecule, amino acid is undoubtedly one of the most basic substances in human body.
There are more than 20 kinds of amino acids that make up the human body. They are tryptophan, methionine, threonine, valine, lysine, histidine, leucine, isoleucine, alanine, phenylalanine, cystine, cysteine, arginine, glycine, serine and tyrosine. Diiodotyrosine, glutamic acid, aspartic acid, proline, hydroxyproline, arginine, citrulline and Ukraine. These amino acids exist in nature and can be synthesized in plants, but the human body cannot synthesize them all. Eight of them are not synthesized by human body and must be provided by food, which are called "essential amino acids". These eight essential amino acids are tryptophan, threonine, methionine, valine, lysine, leucine, isoleucine and phenylalanine. Others are "nonessential amino acids". Histidine can be synthesized in human body, but its synthesis speed can not meet the needs of the body, and some people list it as "essential amino acid". Cystine, tyrosine, arginine, serine and glycine are classified as "semi-essential amino acids" because they can be synthesized in vivo, but their synthetic raw materials are all essential amino acids. Cystine can replace 80% ~ 90% of methionine, and tyrosine can replace 70% ~ 75% of phenylalanine to play the role of essential amino acids. For example, according to its metabolic pathway in the body, it can be divided into "ketogenic amino acids" and "glycogenic amino acids"; According to its chemical properties, it can be divided into neutral amino acids, acidic amino acids and basic amino acids, most of which are neutral.
2. Material basis of life metabolism
The emergence, existence and extinction of life are all related to protein, as Engels said: "protein is the material basis of life, and life is a form of existence in protein." If the human body lacks protein, its physique will be reduced, its development will be delayed, its resistance will be weakened, anemia will be weak, and edema will be formed in severe cases, even life-threatening. Once protein is lost, life will cease to exist, so some people call protein "the carrier of life". Can be said to be the first element of life.
The basic unit of protein is amino acid. If the human body lacks any essential amino acids, it will lead to abnormal physiological function, affect the normal metabolism of antibodies and eventually lead to diseases. Similarly, if the human body lacks some non-essential amino acids, there will also be disorder of antibody metabolism. Arginine and citrulline are very important for the formation of urea. Insufficient intake of cystine will cause insulin decrease and blood sugar increase. For example, the demand for cystine and arginine has greatly increased after trauma. Without it, even if the heat energy is sufficient, protein can't be successfully synthesized. In a word, amino acids can play the following roles in human body through metabolism: ① synthesis of tissue protein; (2) into acid, hormone, antibody, creatine and other ammonia-containing substances; (3) into carbohydrates and fats; ④ Oxidation into carbon dioxide, water and urea to generate energy. Therefore, the existence of amino acids in human body not only provides important raw materials for the synthesis of protein, but also provides a material basis for promoting growth, normal metabolism and maintaining life. If the human body lacks or reduces one of them, the normal life metabolism of the human body will be hindered, and even various diseases or life activities will be terminated. This shows how many amino acids are needed for human life activities.
Second, the position and role of amino acids in food nutrition
In order to survive, human beings must eat food to maintain the normal physiological, biochemical and immune functions of antibodies, as well as life activities such as growth, development and metabolism. The comprehensive process of food being digested, absorbed and metabolized in the body, promoting antibody growth and development, improving intelligence and physique, resisting aging, preventing diseases and prolonging life is called nutrition. The effective ingredients in food are called nutrients.
Protein, lipids, carbohydrates, inorganic salts (that is, minerals, which contain a large number of elements and trace elements), vitamins, water and dietary fiber, which constitute the most basic substances of the human body and are also nutrients needed by the human body. They have their own unique nutritional functions in the body, but they are closely related in the process of metabolism, participating, promoting and regulating life activities together. The body communicates with the outside world through food, keeping the internal environment relatively constant, and completing the unity and balance of the internal and external environment.
What role do amino acids play in these nutrients?
1. The digestion and absorption of protein in the body is completed by amino acids.
Protein, as the first nutrient element in the body, plays an obvious role in food nutrition, but it can't be directly used in the human body, but can be used by becoming small molecules of amino acids. That is, it is not directly absorbed by the human body in the gastrointestinal tract, but is decomposed into low molecular weight peptides or amino acids by various digestive enzymes in the gastrointestinal tract, and then absorbed in the small intestine and enters the liver along the hepatic portal vein. Some amino acids are decomposed or synthesized into protein in the liver; Another part of amino acids continue to distribute to various tissues and organs with blood, and can freely choose to synthesize various specific tissue proteins. Under normal circumstances, the speed of amino acids entering the blood is almost equal to its output speed, so the content of amino acids in normal people's blood is quite constant. If calculated by amino nitrogen, the content is 4-6 mg per 100 ml of plasma and 6.5-9.6 mg per 100 ml of blood cells. After a full meal in protein, a large number of amino acids were absorbed, and the level of amino acids in blood temporarily increased, and the content returned to normal after 6-7 hours. It shows that amino acid metabolism in the body is in a dynamic balance, with blood amino acids as its balance hub, and liver is an important regulator of blood amino acids. Therefore, food protein is digested and decomposed into amino acids and then absorbed by human body, and antibodies use these amino acids to synthesize their own protein. What the human body needs for protein is actually the need for amino acids.
2. Play the role of nitrogen balance
When the quality and quantity of protein in daily diet are appropriate, the nitrogen intake is equal to the nitrogen discharged from feces, urine and skin, which is called the total balance of nitrogen. In fact, it is the balance of continuous synthesis and decomposition between protein and amino acids. Normal people's daily intake of protein should be kept within a certain range. When the intake suddenly increases or decreases, the body can still regulate the metabolism of protein and maintain the nitrogen balance. Excessive intake of protein, beyond the body's regulatory capacity, will destroy the balance mechanism. If you don't eat protein at all, the tissue proteins in your body will still decompose and negative nitrogen balance will continue to appear. If measures are not taken to correct it in time, the antibody will eventually die.
Step 3 turn into sugar or fat
α -keto acids produced by amino acid catabolism are metabolized along different sugar or fat metabolic pathways. α-keto acids can be synthesized into new amino acids, or converted into sugar or fat, or decomposed into CO2 and H2O through cyclic oxidation of tricarboxylic acid, releasing energy.
4. Participate in the formation of enzymes, hormones and some vitamins.
The chemical essence of enzymes is protein (amino acid molecular composition), such as amylase, pepsin, cholinesterase, carbonic anhydrase, transaminase, etc. The nitrogen-containing hormone is protein or its derivatives, such as growth hormone, thyroid stimulating hormone, adrenaline, insulin, intestinal juice stimulating hormone, etc. Some vitamins are converted from amino acids or exist in combination with protein. Enzymes, hormones and vitamins play a very important role in regulating physiological functions and catalyzing metabolism.
5. The demand for essential amino acids in human body
Adults' demand for essential amino acids is about 20%-37% of that of protein.
Third, the application in medical treatment.
Amino acids are mainly used to prepare compound amino acid infusion in medicine, and also used as therapeutic drugs and synthetic peptides. At present, there are more than 100 kinds of amino acids used as drugs, including 20 kinds of amino acids that constitute protein and more than 100 kinds of amino acids that constitute non-protein.
Compound preparation composed of various amino acids plays a very important role in modern intravenous nutrition infusion and "element diet" therapy. It plays an active role in maintaining the nutrition of critically ill patients and saving their lives, and has become one of the indispensable medical varieties in modern medicine.
Amino acids such as glutamic acid, arginine, aspartic acid, cystine and levodopa can be used alone to treat some diseases, mainly for treating liver diseases, digestive tract diseases, encephalopathy, cardiovascular diseases and respiratory diseases, as well as improving muscle vitality, pediatric nutrition and detoxification. In addition, amino acid derivatives are also promising in cancer treatment.
Fourth, the relationship with aging.
If the elderly lack protein, they will decompose more and synthesize more slowly. Therefore, generally speaking, the elderly need more protein than young adults, and the demand for methionine and lysine is also higher than young adults. People over the age of 60 should consume about 70g of protein every day, and it is required that protein contains all kinds of essential amino acids in proper proportion, so as to achieve high-quality protein and prolong life.
Yu Chuanlong (China Medical Science and Technology Press)
Amino acids and health of the elderly
The American space shuttle Discovery sent Glenn (77), the world's oldest astronaut, into space. For the elderly, this day is called the greatest day and the most eye-catching day. Glenn will explore space again in his later years. He wants to help medical science experiments. Protein decomposition of the elderly and the biological experiment of human amino acids are important research. Amino acids and the health of the elderly should be studied not only on earth, but also in space. Because amino acids are related to the life span and aging of the elderly, this is too important. Why is it important? You will know in the following paragraphs. 1. Physiological changes and amino acids in the elderly
It is generally believed that people are old after 60. The physiological and nutritional status of the elderly changes with the progress of the elderly. The changes of protein in the elderly can be summarized in two ways: one is to synthesize tissue protein and various active substances; The second is decomposition, which organizes protein decomposition to produce energy and waste. For growing infants and adolescents, synthesis is greater than decomposition, so the body grows gradually; For the average adult, synthesis equals decomposition, so the weight is relatively stable. For the elderly, in the process of human aging, protein metabolism is dominated by decomposition, while synthetic metabolism is gradually slow, and protein in the body is gradually consumed, often showing a negative nitrogen balance. For example, hemoglobin synthesis is reduced, so anemia is a common senile disease; Due to the function of enzymes and the decrease of small intestine function, protein is not fully decomposed during absorption, and peptides in the body increase and free amino acids decrease. Low renal function in the elderly affects the reabsorption of amino acids, and the decline of liver function also reduces the utilization rate of peptides. In recent years, it has been reported that the elderly are given the same nutritional conditions as young adults, but the plasma amino acids (Valeriana officinalis, leucine, lime, eggs, silk and alanine) of the elderly are reduced, especially the branched-chain amino acids (Valeriana officinalis, leucine and isoleucine) are insufficient. Some people think that high concentration of branched-chain amino acids can provide synthesis. When supplying branched-chain amino acids, it can provide energy by producing adenosine triphosphate (ATP), reduce protein decomposition and enhance the synthesis of protein by promoting insulin secretion. Branched-chain amino acids have been used to maintain nitrogen balance and promote protein synthesis abroad. There are amino acids for liver disease, kidney disease and children in China.
Due to the absorption or utilization of amino acids. Aging affects immune function, and changes in immune activity also affect the functions of other organs. Such as infection, cancer, immune complex disease, autoimmune disease, amyloidosis and other diseases increase in the elderly, which easily leads to aging and death.
Amino acids and longevity
In order to promote the health of the elderly, such as anti-aging, improving the body's resistance and promoting the function of immune mechanism, food needs to be rich in trace elements or sugars. However, the material basis of immunity is protein, and there is no immune substance in human body that is not made of protein. Such as immunoglobulin, antibody, antigen, complement, etc. Even the content of protein in white blood cells, lymphocytes and phagocytes is above 90%. Therefore, if the human body is not short of protein or amino acids, the above trace elements and polysaccharides will play a role. If it is missing, no amount of use is useless. With the development of nutrition and biochemistry, new research shows that although the human body can synthesize some non-essential amino acids, it is easy to lack them in severe stress (including mental stress, anxiety and ideological burden) or some diseases. If it is lacking, it will have a bad influence on the human body. These amino acids are called conditionally essential amino acid. Such as taurine, arginine and glutamine.
Under normal circumstances, the lack of essential amino acids will reduce the immune response of body fluids. For example, in tryptophan-deficient rats, IgG and IgM receptors are inhibited, but normal antibody production can be maintained when tryptophan is supplemented again; The lack of phenylalanine and tyrosine can inhibit the reaction of rat immune cells to tumor cells; The deficiency of methionine and cystine can also lead to the obstacle of antibody synthesis. It has been proved that the balance of amino acids also has this adverse effect. Therefore, essential amino acids play an important role in immunity. To prolong the life span of the elderly, we must improve immunity and pay attention to the supply of essential amino acids. At present, the essential amino acids closely related to life span are:
Taurine: The source of taurine in human body is self-synthesis and intake from diet. The biosynthesis of taurine is that methionine is converted into cystine by vulcanization and then synthesized by cystine. After a series of enzymatic reactions, many higher animals, including humans, have lost the ability to synthesize enough taurine to maintain the overall level of taurine in their bodies, so they need to take taurine from their diet to meet their needs. It is reported that taurine plays a role in the aging of the central nervous system; The degeneration of nervous system in old age is one of the most complicated and profound processes in all systems of the whole body. The aging of central nervous system has obvious changes in morphology or biochemistry, and the mechanism of synthesis, release, reabsorption and transport of monoamine and amino acid neurotransmitters has increased year by year. Lipofuscin is a characteristic substance in the aging process, and the increase of lipofuscin in the brain is one of the signs of nerve aging. When a large amount of lipofuscin accumulates in the cytoplasm of neurons, the nucleus and cytoplasm are compressed and deformed, which affects the normal metabolic function of neurons. The content of lipofuscin in tissues increases obviously during aging, but taurine can decrease it, increase the activity of superoxide dismutase (SOD), and inhibit the modification of low density lipoprotein (LDL) by malondialdehyde (MDA), a product of lipid peroxidation. At the same time, the reaction product of taurine and glucose shows strong antioxidant effect, which can prevent egg yolk lecithin from being oxidized into lipid peroxide, so it has obvious anti-aging effect.
Arginine: Although arginine is not an essential amino acid, it cannot maintain nitrogen balance and normal physiological function under severe stress (such as disease or injury) or arginine deficiency, so it is a conditionally essential amino acid. According to the latest theory, arginine is an essential substance in the enzymatic metabolic pathway of nitric oxide (NO) reacting with citrulline. The main biochemical function of NO or relaxation factor derived from endothelial cells is to stimulate the body to increase the level of cyclic guanylate in phagocytes and stimulate the production of interleukin to regulate the phagocytic function of macrophages. Arginine-related NO enzyme system has also been found in vascular endothelial cells, Cooper's cells in brain tissue and liver, which can lead to hormone secretion in these organs and tissues, thus playing an immune role. Amino acid injection can also be used to improve the immunity of the elderly.
Glutamine: Under normal circumstances, it is a non-essential amino acid. However, under stress conditions such as strenuous exercise, injury and infection. The demand for glutamine greatly exceeds the ability of the body to synthesize glutamine, which reduces the content of glutamine in the body, and this decrease will reduce the synthesis of protein, atrophy of intestinal mucosa and low immune function, so it is also called conditionally essential amino acid.
Recently, it is found that the intestine is the largest immune organ and the third barrier of the human body. The first two barriers are blood-brain barrier and placental barrier. If there is no nutrition supply in the intestine, the intestine will be malnourished, which will weaken the immune function of the intestine and lead to bacterial translocation. Animal experiments have proved that if animals are supplemented with total intravenous infusion or essential diet without glutamine, the villi of small intestine will shrink, the intestinal wall will become thinner and the intestinal immune function will be reduced. Intravenous infusion of 2% glutamylase (about 25% of total amino acids) has a significant effect on restoring intestinal villi atrophy and immune function. Glutamine plays an important role in maintaining the function of intestinal mucosa and improving the immunity, especially for the elderly.
How to scientifically supplement amino acids for the elderly
With the increase of age, the amount of amino acids required by the elderly decreases. The protein quality of a healthy elderly protein is 60% ~ 70% of that of young adults. This may be related to the decrease of skeletal muscle, but it can't be concluded that protein needs to decrease in the elderly. The elderly are mainly catabolic, with decreased secretion of gastric juice and pepsin, decreased acidity of gastric juice and decreased digestion and absorption of protein. In addition, the intake of heat energy is low, and the retention of dietary nitrogen is reduced, so the elderly need less protein than adults. Generally speaking, in a normal diet, the intake of protein is 0.7 ~ 1.0g/kg body weight to maintain the nitrogen balance, and 1.0 ~ 1.2g/kg body weight to achieve the balance. Accordingly, the daily supply of protein is about 60 ~ 75g, of which 1/3 is animal protein. If the heating ratio in protein is considered, 12% ~ 14% is more suitable. The study of amino acid metabolism shows that the requirements of threonine, tryptophan and methionine are different from those of young people, so the suitable pattern of essential amino acids can change with age. Therefore, the quality of protein supply for the elderly is more important. Generally speaking, drinks and food are rich in essential amino acids, which is beneficial to the synthesis of protein.
It is suggested that the reasonable structure of the daily diet of the elderly is:
1. An egg; 2. A bowl of milk (not necessarily with sugar); 3.500g of fruits and vegetables (variety); 4. 100g clean meat, including livestock, poultry and fish; 5.50g of bean products (including tofu, yuba, thousand pieces, bean cakes and various beans themselves).
Products, such as douchi, douchi, boiled whole beans); 6.500 grams of grain (including rice, flour, miscellaneous grains, potatoes and sugar); 7. Drink soup every day, one bowl for each meal; 8. If you are weak and sick, take 50 ml of amino acid oral liquid every morning and evening and replenish it quickly.
Nutrition.
These eight items are based on the value of "one". The purpose is generalization and vagueness, and all projects have great freedom. For example, vegetable varieties can be selected and changed; Meat can be one or more kinds, put in meals and soup, etc. Of course, it can also be made into more forms; Meat and beans can be transformed into each other and complement each other. For example, milk can be replaced by dairy products, yogurt and milk powder. Xiyangyang Feng Ba amino acid oral liquid is made of crystalline L- amino acid, which is prepared according to human milk and FAO/ WHO model. It can be directly absorbed by human body and is a good nutritional supplement.
Can meet the requirements of protein and amino acids, and ensure anti-aging.
New concept of amino acid nutrition and health care
How to choose nutrition and health products correctly? This is a common problem in the process of gradually improving the quality of life today. Some are aimed at the needs of their own condition at that time: for example, taking nutritional preparations to increase white blood cells after radiotherapy and buying nutritional products to supplement calcium after fracture; For example, postpartum women are used to adding blood-enriching drinks, and athletes often have to buy health care products that increase "energy". The latter is determined according to the needs of a certain period and a certain state.
In fact, the concept of modern nutrition has entered a new era: people (not necessarily patients) should seek a universal, basic and necessary nutrient, which is suitable for disease state and health state, especially for sub-health state that is gradually recognized by people and exists objectively. This nutrient should play a non-specific role in strengthening physique, strengthening antibody defense mechanism, improving quality of life and delaying aging, which is amino acid nutrition.
Amino acid is the basic unit of protein. People's life activities depend on countless kinds of protein, and these countless kinds of protein are made up of more than 20 kinds of amino acids in the body through different arrangements and combinations. Although these twenty amino acids are derived from human food, not all of them are directly provided by food. Some need to be synthesized in vivo. Eight amino acids can't be synthesized or the speed of synthesis can't meet the requirements of antibody, so they must be supplied directly from the outside. The ways to supplement amino acids directly from the outside are: some special foods, amino acid infusion and amino acid oral liquid.
A variety of protein composed of amino acids constitute different organs, tissues, muscles and so on. It is easy to understand that they need synthesis, decay, repair and renewal, and amino acids need to be continuously ingested, utilized and synthesized. However, some bioactive substances such as enzymes, antibodies, neurotransmitters, etc., which are indispensable to human life activities, are constantly being utilized and decomposed, and amino acids need to be constantly supplemented for synthesis, which is the necessity of eight essential amino acids for human body. It is not as tangible as the former, and it is not easy for people to know.
Judging from the aging process of people. With age, brain tissues and brain cells as the central nervous system are prone to lack of lysine, tryptophan, arginine, glutamic acid and 5- hydroxytryptamine, leading to Alzheimer's disease and Parkinson's disease. On the cardiovascular side, it is often easy to lack high-density lipoprotein cholesterol, and the elastic layer in blood vessels decreases, leading to atherosclerosis; Lack of methionine in the liver is easy to form fatty liver, and the utilization rate of peptides is reduced; In the kidney, due to the lack of leucine, isoleucine and valine and low renal function, the absorption of amino acids is reduced; In the gastrointestinal system, due to the lack of histidine, the digestion and absorption function of gastrointestinal wall is impaired; In the exercise system, because the protein decomposition process exceeds the synthesis process, muscle fibers decline and shrink, energy supply decreases, and limbs are prone to weakness; In addition, as the immune mechanism of human defense system, the formation and activity of antibody, complement and phagocyte all need the supplement of amino acid-protein. Once it is insufficient, the resistance of the elderly will drop and various diseases will easily occur. Arginine has a direct impact on the level of sexual activity, while aspartic acid has a direct impact on intelligence and memory.
From the mechanism of human fatigue. In the normal activities and sports of human body, the consumption of energy will produce a large number of acidic substances and produce too many free radicals; When the supply of amino acids is insufficient, that is, the raw materials for synthesizing antioxidant enzymes and antioxidants are insufficient, the accumulation of free radicals and acidic substances will accelerate cell division and tissue aging; Too many free radicals, the small one is the mechanism of fatigue, and the big one is the mechanism of aging. Specific experiments have proved that antioxidant enzymes and antioxidants that can scavenge free radicals include lysine and methionine. Once supplemented, the ability of antibody to oxidize and utilize fatty acids will be enhanced, and its effect on fatigue prevention and rapid recovery after fatigue is extremely obvious.
From the analysis of the two physiological processes of delaying aging and resisting fatigue, and on the basis of understanding the importance of amino acid nutrition and its advantages over other single nutrition, the daily demand data of human amino acids (the ratio of essential and non-essential amino acids according to WHO standards) are obtained by scientific experiments, that is, the daily demand of an adult (based on 60 kg standard) is about 5 grams. According to this data, it is appropriate for the elderly, the infirm and the sub-health state to be higher than 30%, and because of the lack of natural synthesis of essential amino acids in the body, it should be supplemented from external sources. In addition to a reasonable and balanced diet, amino acid infusion for injection can be carried out at intervals and in moderation; Oral amino acid oral liquid is a physiological, economical, safe, non-antigenic, easy to absorb and non-toxic method.
To sum up, according to the requirements of modern quality of life, the concept of amino acid nutrition has been sublimated into an "amino acid culture", and amino acid nutrition is indispensable and comprehensive support and reinforcement for human body and quality of life. It is related to people's health quality, quality of life, ability to resist diseases, delay the aging process, resist and recover fatigue, and is a real health-care nutrition. Because of this, the governments of developed countries such as the United States have listed amino acids as the first choice of national health care products. With China's reform and opening up, economic development and the improvement of people's awareness of health care and nutrition, the demand for amino acid nutrition will gradually increase.
Knowledge of amino acids-the important role of amino acids in human body
The World Health Organization (WHO) lists protein as one of the main essential nutrients for human body. The nutritional function of protein is actually the nutritional function of amino acids. The main effects of amino acids on human health are mainly reflected in the following aspects:
1, providing nutrition for the body. 2, regulate the body function, some amino acids can effectively regulate the balance of the human endocrine system. 3. Enhance immunity. 4. Maintain cardiovascular function. 5. Improve liver and kidney function. 6. Reduce the harm caused by radiotherapy and chemotherapy. 7. Promote hormone secretion. 8. Promote the synthesis of protein.