Vitamins are substances, very small quantities of which are necessary for the normal development and functioning of the body. They play a primary role in metabolism, regulation of the processes of absorption and use of basic nutrients - proteins, fats and carbohydrates. Vitamins play a huge role in maintaining the normal physiological state of the nervous, cardiovascular, digestive, endocrine systems and hematopoietic organs. Consuming sufficient amounts of vitamins helps strengthen the body, increase its performance and resistance to various harmful environmental influences and diseases. A lack of vitamins, on the contrary, leads to a weakening of the body and the development of characteristic diseases - hypo- and avitaminosis, in which metabolism and most body functions are disrupted.
Some vitamins are synthesized in the body, but most come from food. It is especially important to monitor vitamin balance for older people. In old age, for example, circulatory disorders are often observed, as a result of which the transfer of vitamins from the blood to the tissues and organs worsens. Often during this period, disturbances in the functioning of the gastrointestinal tract and liver are observed, which leads to a deterioration in the absorption of vitamins. Therefore, older people need to consume more vitamin-rich foods, in such a way that the body receives increased amounts of vitamins.
The required levels of many vitamins increase significantly during intense physical work, pregnancy, and in cold and very hot climates.
Products of plant origin contain most of the vitamins necessary for humans. For many people, plant foods serve as the body's main source of essential vitamins. Moreover, some plants are so rich in certain vitamins that they can serve not only as a means of preventing and treating HPP deficiency, but also be used to treat other diseases for which the use of large quantities of certain vitamin substances is indicated.
Vitamin A (axerophthol, retinol)
This vitamin is widely distributed in nature. Oya is found in products of animal origin (fish oil, liver, dairy products, etc.). However, only about half of the daily requirement for vitamin A is met from these foods. The rest is compensated by plant products that contain the pigment carotene, which is converted in the body under the influence of the enzyme carotypase into vitamin A. But carotene (provitamin A) is three times weaker than the latter and, therefore, it must be consumed three times more. So, if the body’s daily need for vitamin A is 1.5 mg, then approximately 4.5 mg of carotene is required. The fruits and edible parts of the plant, colored orange-red or green, are richest in carotene. There is a lot of carotene in carrots, red peppers, tomatoes, parsley, crabgrass, sorrel, spinach, lettuce, green onions, peaches, apricots, rowan, sea buckthorn, and rose hips.
Since carotropin and vitamin A are deposited in the body and accumulated excess amounts can persist for more than a year, it is advisable to consume more foods containing this vitamin in the summer-autumn period. For example, in well-fed people, vitamin A reserves in tissues can be used up within 2-3 years. The absence or deficiency of vitamin A in food leads to disruption of metabolic processes and, as a consequence, to growth inhibition, exhaustion, dysfunction of the nervous system, decreased function of various glands, horny skin, and decreased resistance to infections. One of the serious manifestations of vitamin A deficiency is hemerolopia (“night blindness”), which is expressed in the loss of visual acuity, especially in twilight and darkness.
Therefore, people whose work is associated with eye strain (pilots, machinists, drivers, typesetters, proofreaders, etc.) need increased amounts of vitamin A. Vitamin A is used as a remedy for diseases of the skin, eyes, liver, infectious diseases, goiter , atherosclerosis and hypertension.
Vitamin B 1 (thiamine, aneurin)
Thiamine is found in small quantities in many plants, but the richest in it are wheat germ, rice bran, oatmeal and buckwheat, peanuts, and green peas. There is a lot of it in pork. The daily requirement of an adult for this vitamin is 2-3 mg. Since vitamin B1 is not stored in the body, it must be regularly supplied with daily food. It should be noted that with intense physical work, during extreme heat and consumption of large amounts of carbohydrate foods, the need for vitamin B1 increases.
This vitamin promotes the growth of the body, has a normalizing effect on gastric motility and the acidity of gastric juice, affects fat metabolism, the cardiovascular and nervous systems, and the endocrine glands. Lack of vitamin B1 in food leads to incomplete combustion of carbohydrates and the accumulation in the body of products of their intermediate metabolism, which have a particularly harmful effect on the peripheral and central nervous systems.
With a long-term lack of vitamin B1, a serious disease called “beriberi” can develop. In patients, appetite sharply worsens and digestion is upset, weakness, palpitations, dizziness and other painful phenomena appear. Then polyneuritis occurs, accompanied by severe pain and loss of skin sensitivity, especially the arms and legs.
In clinical practice, vitamin B1 is widely used in the treatment of diseases of the nervous, cardiovascular and endocrine systems, digestive organs, gout, skin and eye diseases, in surgery and obstetrics.
Vitamin B 2 (riboflavin)
Riboflavin is found in mushrooms, vegetables, grains, peanuts and many other plants. Among plant foods, the richest in vitamin B2 are green peas, buckwheat, and wheat bread; among animal products, they are meat, liver, kidneys, cow's milk, and eggs. The daily requirement for an adult is 2.5-3.5 mg. It is necessary for the synthesis of protein and fat, normal function of the liver and stomach, participates in the process of hematopoiesis, affects the growth and development of the fetus, normalizes vision and protects the eyes from the harmful effects of ultraviolet rays.
With a lack of vitamin B2, a person’s lips, mucous membrane of the mouth and tongue become inflamed, which becomes purple-red and swollen, cracks and ulcers appear in the corners of the mouth. Dermatitis of the face and chest occurs, inflammation of the mucous membrane of the eyelids and cornea with lacrimation, burning and photophobia. There is loss of appetite, headaches, and a sharp decrease in performance.
As a remedy, vitamin B2 is used for certain diseases of the digestive system, heart, endocrine system, skin, eye and infectious diseases and in obstetric practice.
Vitamin B 3 (pantothenic acid)
Pantothenic acid is necessary for normal metabolism, affects oxidation processes, and promotes the growth of epidermal tissue. It is found in animal and plant products. It is rich in nuts, legumes, potatoes and grain products. The approximate daily human need for pantothenic acid is 10 mg.
Signs characterizing insufficient intake of this vitamin from food have not been precisely identified. Pantothenic acid deficiency during pregnancy is dangerous, which can lead to premature birth, developmental defects and death of newborn children.
Vitamin B 6 (pyridoxine)
It is found in significant quantities in many animal products. Vitamin B6 is found in small quantities in plants (legumes, grains, vegetables, fruits, etc.). Its sources are brewer's yeast, wheat, barley, millet, corn, peas, and beans. There is especially a lot of it in bananas.
An adult needs to receive 2 mg of vitamin B6 per day. This vitamin is involved in the metabolism, primarily of proteins and fats, stimulates hematopoiesis, the development of natural immunity to certain diseases, as well as bile secretion and the acid-forming function of the stomach.
Deficiency of pyridoxine causes seizures and hypochromic anemia in infants. In adults, loss of appetite, nausea, drowsiness, increased irritability and psychotic reactions, dry dermatitis of the face, head, neck, chest, inflammation of the lips, tongue, and conjunctivitis are observed. However, since vitamin B6 is widely found in animal and plant foods, illnesses caused by its deficiency are extremely rare. This vitamin is successfully used in the treatment of atherosclerosis, liver, kidney and stomach diseases, tuberculosis, anemia, diseases of the nervous system and some intoxications.
Folic acid
This vitamin is found in animal and plant foods in very small quantities. Moreover, it acquires a biologically active form only during the digestion process. Among plant foods, lettuce, parsley, spinach, beets, potatoes, tomatoes, beans, beans, wheat, rye, baker's and brewer's yeast can serve as a satisfactory source of folic acid. It is through these products that most of the body's daily need for folic acid is covered, determined at approximately 2-3 mg. The missing amount of vitamin is synthesized in the human intestine by intestinal flora. The need for this vitamin increases significantly during pregnancy, childbirth and the development of young children. Folic acid along with vitamin B12 is of primary importance in the process of hematopoiesis of red and white blood. In addition, it is involved in protein and fat metabolism. With poor nutrition
(lack or limitation of animal proteins, green vegetables) a deficiency in folic acid may occur, which entails a disease manifested, in particular, by severe inflammation of the tongue and oral mucosa, a sharp decrease in the acidity of gastric juice, diarrhea and a special form of anemia.
Folic acid is used in the treatment of anemia (usually together with vitamin B12), atherosclerosis and some other diseases.
Para-aminobenzoic acid
It is found in some animal products and plants. Among plant products, most of it is found in mushrooms, rice bran, wheat germ, plant seeds, spinach, and peanuts. As a component, it is part of folic acid. It is the participation in the synthesis of folic acid that determines its importance for the body. The body's quantitative need for para-aminobenzoic acid has not been established. As a remedy, it alleviates the course of typhus, protects against intoxication with certain arsenic and antimony preparations, and its 15% ointment is used to protect the skin from sunburn.
Vitamin B 12
This vitamin is found in animal products. It is practically absent in plants. Vitamin B12 is involved in protein and fat metabolism, improves blood composition.
Vitamin B 15 (pangamic acid)
Vitamin B15 is found in the germinal part of the seeds of many plants and sprouts, in almonds and other kernels of stone fruits. The daily requirement for it does not exceed 2 mg. Pangamic acid activates the exchange of oxygen in tissue cells, stimulates the function of the adrenal glands, promotes the restoration of liver tissue, etc. In recent years, vitamin B15 has been successfully used in a complex of treatments for certain heart diseases, atherosclerosis, rheumatism and liver diseases, especially those that arise due to chronic alcoholism.
Vitamin H (biotin)
Found in peas, soybeans, cauliflower, onions, mushrooms, wheat flour and many other foods. There is a lot of it in the yolk of a chicken egg, beef liver, swine kidneys, and heart.
The body's need for this vitamin has not been precisely established. In any case, with an average diet, a person receives quite a sufficient amount of it.
Biotin is involved in metabolism and apparently plays a special role in the metabolic processes of human skin. Biotin deficiency in adults was observed only in a clinical experiment. In young children with biotin deficiency, skin inflammation develops with peeling and gray pigmentation on the neck, arms and legs, exacerbation of skin sensitivity, inflammation of the tongue, nausea, depression, anemia and cholesterolemia.
Kholin
This is a B vitamin. Significant quantities of it are found in the yolk of chicken eggs, beef, liver, kidneys, herring, salmon, crayfish, and from plant products - in wheat and in the germ of wheat grains, oats, barley, soy flour.
The daily requirement for an adult varies from 250 to 600 mg. Choline participates in fat and cholesterol metabolism, regulating the deposition of these substances in body tissues. In addition, in the form of acetylcholine (a compound of the ester of acetic acid and choline), it is an intermediary in the transmission of nerve impulses in the peripheral nervous system.
With a lack of choline, fatty infiltration of the liver, necrosis of the liver tissue occurs, followed by cirrhosis and even malignant degeneration. Sufficient amounts of choline not only prevent, but can also eliminate fatty liver disease that has already occurred. Therefore, choline is used in the prevention and treatment of its diseases. Along with this, choline inhibits the development of atherosclerotic plaques in the walls of the aorta and heart vessels, which is of great importance in the prevention and treatment of atherosclerosis.
Inositol (mesoinositol)
This substance also belongs to the B vitamins. In plant products it is found in the form of phytic acid and its calcium salt - phytin. Most of it is found in green peas and dry peas, green beans, melon, oranges, cabbage, onions, pears, tomatoes, carrots. Inositol is also found in products of animal origin.
Inositol is involved in fat transfer, although its antihypertensive effect is much weaker than that of choline. It also lowers cholesterol levels in the blood and thereby reduces the possibility of developing atherosclerosis. The daily dose of inositol required by an adult is supposed to be 1 - 1.5 g. Signs of deficiency of this vitamin in humans have not been described.
Vitamin D
This vitamin has antirachitic properties. Currently, several substances are known that exhibit similar properties (pcs are designated vitamins D2, D3, etc.). Vitamin D is found in animal products and only small amounts are found in mushrooms and some higher plants.
Lack of vitamin D in children leads to rickets. They have disturbances in the development of teeth and nails, muscle sagging and abdominal enlargement associated with it. Sick children lag behind in physical and mental development, are more likely to suffer from infectious diseases, etc. Vitamin D is used as a therapeutic agent for certain skin diseases and convulsive conditions (for dysfunction of the parathyroid glands). At the same time, excessive consumption of vitamin D can cause intoxication of the body.
Vitamin E (tocopherol)
Vitamin E is involved in the metabolism of carbohydrates, proteins and fats, and has very high antioxidant activity. It improves the absorption and assimilation of vitamin A, has a stimulating effect on muscle tissue, improves nutrition and blood supply to the uterine muscle, which is especially important during pregnancy. Animal experiments have shown that vitamin E plays an important role in the formation of germ cells and intrauterine development of the fetus.
The best plant sources of tocopherol are green beans, green peas, lettuce, oats, wheat, and corn. There is a lot of it in vegetable oils: sea buckthorn, soybean, corn, cottonseed, sunflower. The daily requirement for a healthy adult is approximately 20-30 mg. The main depot of vitamin E in the body is adipose tissue, which contains nine-tenths of the total amount.
With vitamin E deficiency, metabolic disorders and associated severe damage to various organs and systems may occur. As a remedy, vitamin E is used together with other drugs in some cases of weakened sexual function, diseases of the neuromuscular system, peripheral circulatory disorders, thrombophlebitis and trophic ulcers, diseases of the liver, skin, eyes, as well as atherosclerosis, hypertension, etc.
Vitamin K (phyllohypops)
Several substances are known, designated as vitamin K. One of them (vitamin K1) is formed in the green parts of plants in chloroplasts in connection with chlorophyllin, the other (vitamin K2) - in bacteria that live in the human large intestine. In 1942, the substance vikasol was synthesized, which was 2-3 times more biologically active than vitamins K1 and K2.
Plant foods such as spinach, tomatoes, peas, carrots, parsley, as well as legumes, berries, and berries are rich in vitamin K.
Vitamin K is essential for the normal blood clotting process. In particular, it is involved in the formation of prothrombin in the liver. A deficiency in this vitamin can lead to multiple small subcutaneous and intramuscular hemorrhages, and in case of injury - to life-threatening bleeding. In addition, vitamin K affects the contractile properties of myosin, enhances contraction and peristalsis of the stomach and intestines, and takes part in the respiration of all cells and intracellular metabolism.
Diseases associated with a lack of vitamin K in food practically do not occur, since it is produced by “beneficial” bacteria in the intestines. However, vitamin K deficiency can still occur in severe diseases of the gallbladder and other diseases, when bile does not enter the intestines and, as a result, the absorption of fats and vitamin K dissolved in them is impaired. Vitamin K deficiency can sometimes also be associated with intestinal disease, in which it is produced and absorbed.
Newborns who do not yet have vitamin K-producing bacteria in their intestines receive it through breast milk. The daily requirement of a newborn for vitamin K is 10-15 mg.
As a therapeutic agent, vitamin K is successfully used for pulmonary and gastrointestinal bleeding, hemorrhagic diathesis in newborns, in surgical and dental practice, as well as for some diseases of the intestines, liver, and lungs.
Vitamin P (rutin, tea catechins)
This is found in vegetables, berries, citrus fruits, and tea. The quantitative need for it has not been precisely established. This vitamin reduces the increased permeability of the walls of blood vessels caused by various reasons. It is prescribed for hemorrhagic diathesis, rheumatism, hypertension, peptic ulcer of the stomach and duodenum, some diseases of the liver and gallbladder, eyes, skin, poisoning and in obstetric practice. Vitamin P is often used in combination with vitamin C.
Vitamin PP (nicotinic acid)
Certain amounts of this vitamin are found in many grains, legumes, vegetables, and fruits. Animal products are richer in it. Nicotinic acid is partially synthesized in the human body itself from tryptophan, a component of the dietary protein.
The daily human need for nicotinic acid is 15-20 mg. It is very necessary for the body, since it is part of enzymes that take part in oxidative processes. With a lack of this vitamin, a disease may develop in which appetite worsens, pain in the stomach, nausea, diarrhea, severe weakness, and worsening memory appear. Longer-term deficiency of vitamin PP leads to pellagra (this is a word of Italian origin, it is translated as “rough skin”). This disease causes severe damage to the gastrointestinal tract, skin and central nervous system, even leading to serious mental disorders. The lack of other vitamins also plays a role in the origin of pellagra: B1, B2, B6. Nicotinic acid is used in the treatment of atherosclerosis and some other diseases of the cardiovascular system, respiratory and digestive organs, nervous system, skin, eyes and diabetes.
Vitamin C (ascorbic acid)
A person provides himself with this vitamin, which is very important for the functioning of the body, mainly through plant foods. Rich in vitamin C are black currants, rosehips, rowanberries, sea buckthorn, gooseberries, strawberries, oranges, lemons and many other berries and fruits, and vegetables include green and red peppers, green onions, horseradish, parsley, dill, spp., tomatoes and some others. plants. Ascorbic acid is involved in the metabolism of nucleic acids, the exchange and synthesis of steroid hormones of the adrenal cortex and thyroid gland, takes part in the oxidation of a number of amino acids and the synthesis of many substances necessary for the construction of connective and bone tissue. Vitamin C ensures normal capillary permeability, increases the elasticity and strength of blood vessels. It plays a major role in maintaining the body's natural and acquired resistance to infectious diseases.
Chronic deficiency of vitamin C can lead to scurvy. With this disease, weakness, lethargy, depressed mood, and muscle pain initially appear. Then the gums begin to loosen and bleed, teeth become loose and fall out, and multiple hemorrhages occur in the skin, muscles, joints, and internal organs. Anemia develops, the activity of the cardiovascular and other body systems is disrupted.
Scurvy is now rare. Much more often, doctors have to deal with less pronounced, so to speak, hidden forms of vitamin C deficiency. In such cases, performance decreases, apathy and fatigue appear, resistance to toxic substances and to the effects of high and low temperatures decreases, a person becomes more predisposed to colds, flu and other infectious diseases; wounds and bone fractures do not heal well. A lack of vitamin C leads to changes in the vascular wall and thereby creates favorable conditions for the development of atherosclerosis (especially in people with excess nutrition and a sedentary lifestyle)
To avoid vitamin C deficiency, it is necessary to consume a sufficient amount of plant products - natural sources of ascorbic acid, and in the winter-spring period, when the vitamin C content in them is significantly reduced, you can take additional tablets with synthetic ascorbic acid. On average, an adult needs about 70 mg of vitamin C per day; children under 7 years old need 50 mg. For heavy physical work, pregnancy and for lactating women, the dose increases to 100-120 mg. For people living in the Far North or in areas with a hot climate, the need for ascorbic acid increases by 30-50%, and sometimes by 100%. As a remedy, vitamin C is widely used in the treatment of atherosclerosis, various diseases of the cardiovascular system, respiratory organs, kidneys, liver, endocrine nervous systems, blood diseases, joints, tuberculosis, poisoning with chemical poisons, in obstetrics and surgery.
Vitamin F
Vitamin F is an unsaturated fatty acid - linoleic, lpnolenic and arachidonic, which is found in vegetable edible oils (sunflower, corn, nut, soybean, cottonseed, olive, flaxseed, etc.) and animal fats. The daily dose of vitamin F for an adult is determined to be approximately 1-2 g. It is usually recommended to consume 20-30 g of vegetable oil containing this vitamin daily.
Unsaturated fatty acids promote the absorption of fats, participate in the fat metabolism of the skin, and affect the processes of lactation and reproduction. Vitamin F converts cholesterol into soluble compounds and thereby facilitates its removal from the body. Due to this, unsaturated fatty acids are used for the prevention and treatment of atherosclerosis. In addition, they are used in the treatment of certain skin diseases (eczema, ulcerative lesions, etc.).
Vitamin U
In 1949, it was discovered that fresh juices of certain vegetables, including cabbage, have the property of inhibiting the development of experimental stomach ulcers in experimental laboratory animals. Since the antiulcer factor contained in the juice of cabbage and other plants belongs to nutrients, it has been classified as a vitamin. From the Latin word ulcus, which means “ulcer,” it received the name vitamin U. The work that appeared after the discovery of this vitamin established the significant effectiveness of cabbage juice and some other vegetables in the treatment of peptic ulcers of the stomach and duodenum. In many patients, the painful phenomena quickly passed and scarring of the ulcers occurred. It has been suggested that the antiulcer effect of cabbage juice is due to the presence in cabbage of significant amounts of methylmethioinsulfonium, which is also found in many other vegetables, fruits, cereals, fresh milk, raw egg yolks, and some animal and vegetable fats.
However, many biological studies and clinical observations of patients have shown that the use of pure megplmotnonine sulfonium is less effective than the effect of cabbage juice. Apparently, the antiulcer effect of juice is determined not only by this substance. It was found that the content of vitamin U in plants depends on the conditions and place of their cultivation, the time of harvest, and the method of canning and storage. For example, in the southern regions, where there are many sunny days, vegetables contain much more vitamin U. This vitamin is easily oxidized and destroyed under the influence of high temperature, but at the same time it tolerates drying and cooling well.
Introduction
1 Vitamins
1.1 History of the discovery of vitamins
1.2 Concept and main features of vitamins
1.3 Providing the body with vitamins
2 Classification and nomenclature of vitamins
2.1 Fat-soluble vitamins
2.2 Water-soluble vitamins
2.3 Group of vitamin-like substances
Conclusion
Bibliography
Introduction
It is difficult to imagine that such a well-known word as “vitamin” entered our vocabulary only at the beginning of the 20th century. It is now known that vitamins are involved in vital metabolic processes in the human body. Vitamins are vital organic compounds that are necessary for humans and animals in minute quantities, but are of great importance for normal growth, development and life itself.
Vitamins usually come from plant foods or animal products, since they are not synthesized in the body of humans and animals. Most vitamins are precursors of coenzymes, and some compounds perform signaling functions.
The daily need for vitamins depends on the type of substance, as well as on age, gender and the physiological state of the body. Recently, ideas about the role of vitamins in the body have been enriched with new data. It is believed that vitamins can improve the internal environment, increase the functionality of basic systems, and the body’s resistance to adverse factors.
Consequently, vitamins are considered by modern science as an important means of general primary prevention of diseases, increasing efficiency, and slowing down the aging process.
The purpose of this work is a comprehensive study and characterization of vitamins.
The work consists of an introduction, two chapters, a conclusion and a list of references. The total volume of work is 21 pages.
1 Vitamins
1.1 History of the discovery of vitamins
If you look at books published at the end of the last century, you can see that at that time the science of rational nutrition included the inclusion of proteins, fats, carbohydrates, mineral salts and water in the diet. It was believed that food containing these substances fully satisfies all the body's needs, and thus the question of rational nutrition seemed resolved. However, the science of the 19th century was in conflict with centuries-old practice. The life experience of the population of various countries has shown that there are a number of diet-related diseases that often occur among people whose food does not contain a lack of proteins, fats, carbohydrates and mineral salts.
Practitioners have long assumed that there is a direct connection between the occurrence of certain diseases (for example, scurvy, rickets, beriberi, pellagra) and the nature of nutrition. What led to the discovery of vitamins - these substances that have miraculous properties to prevent and cure severe diseases of high-quality nutritional deficiency?
The study of vitamins began with the Russian doctor N.I. Lunin, who back in 1888 established that for the normal growth and development of an animal organism, in addition to proteins, fats, carbohydrates, water and minerals, some other, as yet unknown, substances are needed science of substances, the absence of which leads to the death of the body.
The proof of the existence of vitamins was completed by the work of the Polish scientist Casimir Funk, who in 1912 isolated a substance from rice bran that cured the paralysis of pigeons that ate only polished rice (beriberi - this is how this disease was called among people in the countries of Southeast Asia, where the population eats mainly one rice). Chemical analysis of the substance isolated by K. Funk showed that it contains nitrogen. Funk called the substance he discovered a vitamin (from the words “vita” - life and “amine” - containing nitrogen).
True, it later turned out that not all vitamins contain nitrogen, but the old name for these substances remained. Nowadays, it is customary to designate vitamins by their chemical names: retinol, thiamine, ascorbic acid, nicotinamide - A, B, C, PP, respectively.
1.2 Concept and main features of vitamins
From a chemical point of view, vitamins is a group of low-molecular substances of various chemical natures that have pronounced biological activity and are necessary for the growth, development and reproduction of the body.
Vitamins are formed by biosynthesis in plant cells and tissues. Usually in plants they are not in an active, but highly organized form, which, according to research, is most suitable for the human body, namely in the form of provitamins. Their role is reduced to the complete, economical and correct use of essential nutrients, in which the organic substances of food release the necessary energy.
Only a few vitamins, such as A, D, E, B12, can accumulate in the body. Lack of vitamins causes severe disorders.
Basic signs vitamins:
Either they are not synthesized in the body at all, or they are synthesized in small quantities by the intestinal microflora;
They do not perform plastic functions;
They are not energy sources;
They are cofactors of many enzymatic systems;
They have a biological effect in small concentrations and affect all metabolic processes in the body; the body requires them in very small quantities: from several micrograms to several mg per day.
Various are known degree of insecurity body vitamins:
avitaminosis- complete depletion of vitamin reserves;
hypovitaminosis- a sharp decrease in the supply of one or another vitamin;
hypervitaminosis- excess vitamins in the body.
All extremes are harmful: both deficiency and excess of vitamins, since with excessive consumption of vitamins, poisoning develops (intoxication). The phenomenon of hypervitaminosis concerns only vitamins A and D; excess amounts of most other vitamins are quickly excreted from the body in the urine. But there is also the so-called subnormal supply, which is associated with a deficiency of vitamins and it manifests itself in disruption of metabolic processes in organs and tissues, but without obvious clinical signs (for example, without visible changes in the condition of the skin, hair and other external manifestations). If this situation is regularly repeated for various reasons, then this can lead to hypo- or vitamin deficiency.
1.3 Providing the body with vitamins
With normal nutrition, the body's daily need for vitamins is fully satisfied. Insufficient, poor nutrition or disruption of the processes of absorption and use of vitamins can cause various forms of vitamin deficiency.
Causes of vitamin depletion in organism:
1) Quality of products and their preparation:
Failure to comply with storage conditions in terms of time and temperature;
Irrational culinary processing (for example, prolonged cooking of finely chopped vegetables);
The presence of antivitamin factors in food (cabbage, pumpkin, parsley, green onions, apples contain a number of enzymes that destroy vitamin C, especially when cut small)
Destruction of vitamins under the influence of ultraviolet rays, air oxygen (for example, vitamin A).
2) An important role in providing the body with a number of vitamins belongs to the microflora of the digestive tract:
In many common chronic diseases, the absorption or assimilation of vitamins is impaired;
Severe intestinal disorders, improper use of antibiotics and sulfa drugs lead to the creation of a certain deficiency of vitamins that can be synthesized by beneficial intestinal microflora (vitamins B12, B6, H (biotin)).
Daily requirement for vitamins and their main functions
| Vitamin |
Daily allowance need |
Functions | main sources |
| Ascorbic acid (C) | 50-100 mg | Participates in redox processes, increases the body's resistance to extreme influences | Vegetables, fruits, berries. In cabbage - 50 mg. In rose hips - 30-2000 mg. |
| Thiamine, aneurin (B1) | 1.4-2.4 mg | Necessary for normal functioning of the central and peripheral nervous system | Wheat and rye bread, cereals - oatmeal, peas, pork, yeast, intestinal microflora. |
| Riboflavin (B2) | 1.5-3.0 mg | Participates in redox reactions | Milk, cottage cheese, cheese, eggs, bread, liver, vegetables, fruits, yeast. |
| Pyridoxine (B6) | 2.0-2.2 mg | Participates in the synthesis and metabolism of amino acids, fatty acids and unsaturated lipids | Fish, beans, millet, potatoes |
| Nicotinic acid (PP) | 15.0-25.0 mg | Participates in redox reactions in cells. Deficiency causes pellagra | Liver, kidneys, beef, pork, lamb, fish, bread, cereals, yeast, intestinal microflora |
| Folic acid, folicin (Vs) | 0.2-0.5 mg | Hematopoietic factor, participates in the synthesis of amino acids and nucleic acids | Parsley, lettuce, spinach, cottage cheese, bread, liver |
| Cyanocobalamin (B12) | 2-5 mg | Participates in the biosynthesis of nucleic acids, hematopoietic factor | Liver, kidneys, fish, beef, milk, cheese |
| Biotin (N) | 0.1-0.3 mg | Participates in metabolic reactions of amino acids, lipids, carbohydrates, nucleic acids | Oatmeal, peas, egg, milk, meat, liver |
| Pantothenic acid (B3) | 5-10 mg | Participates in metabolic reactions of proteins, lipids, carbohydrates | Liver, kidneys, buckwheat, rice, oats, eggs, yeast, peas, milk, intestinal microflora |
| Retinol (A) | 0.5-2.5 mg | Participates in the activity of cell membranes. Necessary for human growth and development, for the functioning of mucous membranes. Participates in the process of photoreception - the perception of light | Fish oil, cod liver, milk, eggs, butter |
| Calciferol (D) | 2.5-10 mcg | Regulation of calcium and phosphorus levels in the blood, mineralization of bones and teeth | Fish oil, liver, milk, eggs |
Currently, about 13 vitamins are known, which, together with proteins, fats and carbohydrates, must be present in the diet of people and animals to ensure the normal functioning of vitamins. In addition, there is a group vitamin-like substances, which have all the properties of vitamins, but are not strictly necessary components of food.
Compounds that are not vitamins, but can serve as precursors for their formation in the body, are called provitamins. These include, for example, carotenes, which are broken down in the body to form vitamin A, and some sterols (ergosterol, 7-dehydrocholesterol, etc.), which are converted into vitamin D.
A number of vitamins are represented not by one, but by several compounds that have similar biological activity (vitamers), for example, vitamin B6 includes pyridoxine, pyridoxal and pyridoxamine. To designate such groups of related compounds, the word “vitamin” is used with letter designations (vitamin A, vitamin E, etc.).
Individual compounds with vitamin activity are given rational names that reflect their chemical nature, such as retinal (the aldehyde form of vitamin A), ergocalciferol, and cholecaldiferol (forms of vitamin D).
Thus, along with fats, proteins, carbohydrates and mineral salts, the necessary complex for maintaining human life includes a fifth component of equal importance - vitamins. Vitamins take a direct and active part in all metabolic processes of the body, and are also part of many enzymes, acting as catalysts.
2 Classification and nomenclature of vitamins
Since vitamins include a group of substances of different chemical natures, their classification by chemical structure is difficult. Therefore, classification is carried out according to solubility in water or organic solvents. In accordance with this, vitamins are divided into water-soluble and fat-soluble.
1 TO water-soluble vitamins include:
B1 (thiamine) antineuritis;
B2 (riboflavin) antidermatitis;
B3 (pantothenic acid) antidermatitis;
B6 (pyridoxine, pyridoxal, pyridoxamine) antidermatitis;
B9 (folic acid; folacin) antianemic;
B12 (cyanocobalamin) antianemic;
PP (nicotinic acid; niacin) antipellagritic;
H (biotin) antidermatitis;
C (ascorbic acid) antiscorbutic – participate in the structure and functioning of enzymes.
2) K fat-soluble vitamins include:
A (retinol) antixerophthalmic;
D (calciferols) antirachitic;
E (tocopherols) antisterile;
K (naphthoquinols) antihemorrhagic;
Fat-soluble vitamins are included in the structure of membrane systems, ensuring their optimal functional state.
Chemically, fat-soluble vitamins A, D, E and K are isoprenoids.
3) the following group: vitamin-like substances. These usually include vitamins: B13 (orotic acid), B15 (pangamic acid), B4 (choline), B8 (inositol), B (carnitine), H1 (paraminbenzoic acid), F (polyunsaturated fatty acids), U (S= methylmethionine sulfate chloride).
Nomenclature(name) is based on the use of capital letters of the Latin alphabet with a lower numerical index. In addition, the name uses names that reflect the chemical nature and function of the vitamin.
Vitamins did not immediately become known to mankind, and over the course of many years scientists managed to discover new types of vitamins, as well as new properties of these substances beneficial to the human body. Since the language of medicine throughout the world is Latin, vitamins were designated in Latin letters, and later also in numbers.
The assignment of not only letters, but also numbers to vitamins is explained by the fact that vitamins acquired new properties, which seemed to be the simplest and most convenient to designate using numbers in the name of the vitamin. For example, consider the popular vitamin B. So, today, this vitamin can be represented in a variety of areas, and to avoid confusion it is called from “vitamin B1” to “vitamin B14”. The vitamins included in this group are also named similarly, for example, “B vitamins.”
When the chemical structure of vitamins was finally determined, it became possible to name vitamins in accordance with the terminology accepted in modern chemistry. Thus, names such as pyridoxal, riboflavin, and pteroylglutamic acid came into use. Some more time passed, and it became absolutely clear that many organic substances, known to science for a long time, also have the properties of vitamins. Moreover, there were quite a lot of such substances. Among the most common, we can mention nicotinamide, pseudoinositol, xanthopterin, catechin, hesperetin, quercetin, rutin, as well as a number of acids, in particular nicotinic, arachidonic, linolenic, linoleic, and some other acids.
2.1 Fat-soluble vitamins
Vitamin A (retinol) is the predecessor of the group " retinoids"to which they belong retinal And retinoic acid. Retinol is formed during the oxidative breakdown of provitamin β-carotene. Retinoids are found in animal products, and β-carotene is found in fresh fruits and vegetables (especially carrots). Retinal causes the color of the visual pigment rhodopsin. Retinoic acid functions as a growth factor.
With a lack of vitamin A, night blindness, xerophthalmia (dry cornea of the eyes) develop, and growth disturbances occur.
Vitamin D (calciferol) when hydroxylated in the liver and kidneys, it forms a hormone calcitriol(1α,25-dihydroxycholecalciferol). Together with two other hormones (parathyroid hormone, or parathyrin, and calcitonin), calcitriol takes part in the regulation of calcium metabolism. Calciferol is formed from the precursor 7-dehydrocholesterol, present in the skin of humans and animals, upon irradiation with ultraviolet light.
If UV irradiation of the skin is insufficient or vitamin D is not available in food products, vitamin deficiency develops and, as a consequence, rickets in children, osteomalacia(softening of bones) in adults. In both cases, the process of mineralization (incorporation of calcium) of bone tissue is disrupted.
Vitamin E includes tocopherol and a group of related compounds with a chromane ring. Such compounds are found only in plants, especially in wheat sprouts. For unsaturated lipids, these substances are effective antioxidants.
Vitamin K general name for a group of substances including phylloquinone and related compounds with a modified side chain. Vitamin K deficiency is quite rare, since these substances are produced by intestinal microflora. Vitamin K takes part in the carboxylation of glutamic acid residues in blood plasma proteins, which is important for normalizing or accelerating the blood clotting process. The process is inhibited by vitamin K antagonists (for example, coumarin derivatives), which is used as one of the treatment methods thrombosis.
2.2 Water-soluble vitamins
Vitamin B1 (thiamine) built from two cyclic systems - pyrimidine(six-membered aromatic ring with two nitrogen atoms) and thiazole (five-membered aromatic ring including nitrogen and sulfur atoms) connected by a methylene group. The active form of vitamin B1 is thiamine diphosphate(TPP), which functions as a coenzyme in the transfer of hydroxyalkyl groups (“activated aldehydes”), for example, in the oxidative decarboxylation reaction of α-keto acids, as well as in the transketolase reactions of the hexose monophosphate pathway. With a lack of vitamin B1, disease develops take it, the signs of which are disorders of the nervous system (polyneuritis), cardiovascular diseases and muscle atrophy.
Vitamin B2 a complex of vitamins, including riboflavin, folic, nicotinic and pantothenic acids. Riboflavin serves as a structural element of the prosthetic groups of flavin mononucleotide [FMN (FMN)] and flavin adenine dinucleotide [FAD (FAD)]. FMN And FAD are prosthetic groups of numerous oxidoreductases (dehydrogenases), where they function as hydrogen carriers (in the form of hydride ions).
Molecule folic acid(vitamin B9, vitamin Bc, folacin, folate) includes three structural fragments: pteridine derivative, 4-aminobenzoate and one or more residues glutamic acid. The product of folic acid reduction - tetrahydrofolic (folinic) acid [THF] - is part of the enzymes that transfer one-carbon fragments (C1 metabolism).
Figure 2 Fat-soluble vitamins
Folic acid deficiency is quite common. The first sign of deficiency is impaired erythropoiesis (megaloblastic anemia). At the same time, the synthesis of nucleoproteins and cell maturation are inhibited, and abnormal erythrocyte precursors - megalocytes - appear. With acute deficiency of folic acid, generalized tissue damage develops associated with impaired lipid synthesis and amino acid metabolism.
Unlike humans and animals, microorganisms are able to synthesize folic acid de novo. Therefore, the growth of microorganisms is suppressed sulfa drugs, which, as competitive inhibitors, block the inclusion of 4-aminobenzoic acid in the biosynthesis of folic acid. Sulfonamide drugs cannot affect the metabolism of animal organisms because they are not able to synthesize folic acid.
A nicotinic acid(niacin) and nicotinamide(niacinamide) (both known as vitamin B5, vitamin PP) are necessary for the biosynthesis of two coenzymes - nicotinamide adenine dinucleotide [ NAD+(NAD+)] and nicotinamide adenine dinucleotide phosphate [ NADP+(NADP+)]. The main function of these compounds, which is to transport hydride ions (reducing equivalents), is discussed in the section on metabolic processes. In animal organisms, nicotinic acid can be synthesized from tryptophan, however, biosynthesis occurs with low yield. Therefore, vitamin deficiency occurs only if all three substances are simultaneously absent from the diet: nicotinic acid, nicotinamide and tryptophan. Diseases. associated with niacin deficiency, proD are skin lesions ( pellagra), stomach upset and depression.
Pantothenic acid(vitamin B3) is the amide of α,γ-dihydroxy-β,β-dimethylbutyric acid (pantoic acid) and β-alanine. Compound required for biosynthesis coenzyme A[CoA (CoA)] involved in the metabolism of many carboxylic acids. Pantothenic acid is also part of the prosthetic group acyl-transport protein(APB). Since pantothenic acid is found in many foods, vitamin deficiency due to vitamin B3 deficiency is rare.
Vitamin B6- group name of three pyridine derivatives: pyridoxal, pyridoxine And pyridoxamine. The diagram shows the formula of iridoxal, where the aldehyde group (-CHO) is in the position at C-4; in pyridoxine this place is occupied by an alcohol group (-CH2OH); and in pyridoxamine there is a methylamino group (-CH2NH2). The active form of vitamin B6 is pyridoxal 5-phosphate(PLP), an essential coenzyme in amino acid metabolism. Pyridoxal phosphate is also included in glycogen phosphorylase, taking part in the breakdown of glycogen. Vitamin B6 deficiency is rare.
Figure 2 Fat-soluble vitamins
Vitamin B12 (cobalamins; dosage form - cyanocobalamin) - a complex compound based on a cycle Corrina and containing a coordinated cobalt ion. This vitamin is synthesized only in microorganisms. Among food products, it is found in liver, meat, eggs, milk and is completely absent in plant foods (note to vegetarians!). The vitamin is absorbed by the gastric mucosa only in the presence of a secreted (endogenous) glycoprotein, the so-called internal factor. The purpose of this mucoprotein is to bind cyanocobalamin and thereby protect against degradation. In the blood, cyanocobalamin is also bound by a special protein, transcobalamin. In the body, vitamin B12 is stored in the liver.
Figure 2 Fat-soluble vitamins
Cyanocobalamin derivatives are coenzymes involved, for example, in the conversion of methylmalonyl-CoA to succinyl-CoA and the biosynthesis of methionine from homocysteine. Cyanocobalamin derivatives take part in the reduction of ribonucleotides by bacteria to deoxyribonucleotides.
Vitamin deficiency or malabsorption of vitamin B12 is associated mainly with the cessation of secretion of intrinsic factor. The consequence of vitamin deficiency is pernicious anemia.
Vitamin C (L-ascorbic acid) is a 2,3-dehydrogulonic acid γ-lactone. Both hydroxyl groups are acidic in nature, and therefore, upon loss of a proton, the compound can exist in the form ascorbate anion. A daily supply of ascorbic acid is necessary for humans, primates and guinea pigs as these species lack the enzyme gulonolactone oxidase(EC 1.1.3.8), catalyzing the last stage of the conversion of glucose to ascorbate.
Sources of vitamin C are fresh fruits and vegetables. Ascorbic acid is added to many drinks and foods as an antioxidant and flavoring agent. Vitamin C breaks down slowly in water. Ascorbic acid, as a strong reducing agent, takes part in many reactions (mainly in hydroxylation reactions).
Of the biochemical processes involving ascorbic acid, mention should be made collagen synthesis, tyrosine degradation, syntheses catecholamine And bile acids. The daily requirement for ascorbic acid is 60 mg, a value not typical for vitamins. Today, vitamin C deficiency is rare. Deficiency manifests itself several months later in the form of scurvy (scorbutus). The consequences of the disease are atrophy of connective tissues, disorders of the hematopoietic system, and tooth loss.
Vitamin H (biotin) found in liver, egg yolk and other foods; in addition, it is synthesized by intestinal microflora. In the body, biotin (via the ε-amino group of the lysine residue) is associated with enzymes, e.g. pyruvate carboxylase(EC 6.4.1.1), catalyzing the carboxylation reaction. When transferring a carboxyl group, two N-atoms of the biotin molecule in an ATP-dependent reaction bind a CO2 molecule and transfer it to the acceptor. Biotin binds with high affinity (Kd = 10 - 15 M) and specificity avidin chicken egg white. Since avidin is denatured when boiled, vitamin H deficiency can only occur when eating raw eggs.
2.3 Group of vitamin-like substances
In addition to the above two main groups of vitamins, there is a group of various chemical substances, some of which are synthesized in the body, but have vitamin properties. The body needs them in relatively small quantities, but the effect on body functions is quite strong. These include:
Essential nutrients with plastic function: choline, inositol.
Biologically active substances synthesized in the human body: lipoic acid, orotic acid, carnitine.
Pharmacologically active food substances: bioflavonoids, vitamin U - methylmethionine sulfonium, vitamin B15 - pangamic acid, microbial growth factors, para-aminobenzoic acid.
Recently, another factor was discovered, called pyrroloquinolinoquinone. Its coenzyme and cofactor properties are known, but its vitamin properties have not yet been discovered.
The main difference between vitamin-like substances is that with their deficiency or excess, various pathological changes characteristic of vitamin deficiencies do not occur in the body. The content of vitamin-like substances in food is quite sufficient for the functioning of a healthy body.
For a modern person, it is necessary to know about the precursors of vitamins. The source of vitamins, as is known, are products of plant and animal origin. For example, vitamin A is found in finished form only in products of animal origin (fish oil, whole milk, etc.), and in plant products only in the form of carotenoids - their predecessors. Therefore, by eating carrots we only receive a precursor of vitamin A, from which vitamin A itself is produced in the liver. Provitamins include: carotenoids (the main one is carotene) - a precursor of vitamin A; sterols (ergosterol, 7-dehydrocholesterol, etc.) - precursors of vitamin D;
Conclusion
So, from the history of vitamins, we know that the term “vitamin” was first used to refer to a specific food component that prevented Beriberi disease, which was common in countries where they ate a lot of polished rice. Since this component had the properties of an amine, the Polish biochemist K. Funk, who first isolated this substance, called it vitamin- an amine essential for life.
Currently vitamins can be characterized as low-molecular organic compounds, which, being a necessary component of food, are present in it in extremely small quantities compared to its main components. Vitamins- these are substances that ensure the normal course of biochemical and physiological processes in the body. Vitamins- a necessary element of food for humans and a number of living organisms, because are not synthesized or some of them are synthesized in insufficient quantities by this organism.
Primary source Vitamins are plants, where they are mainly formed, as well as provitamins - substances from which vitamins can be formed in the body. A person receives vitamins either directly from plants, or indirectly through animal products in which vitamins were accumulated from plant foods during the life of the animal.
Vitamins are divided into two large groups: fat-soluble vitamins and water-soluble vitamins. In the classification of vitamins, in addition to the letter designation, the main biological effect is indicated in brackets, sometimes with the prefix “anti,” indicating the ability of a given vitamin to prevent or eliminate the development of the corresponding disease.
To fat-soluble vitamins include: Vitamin A (antixerophthalic), Vitamin D (antirachitic), Vitamin E (reproduction vitamin), Vitamin K (antihemorrhagic)\
For water-soluble vitamins include: Vitamin B1 (antineuritis), Vitamin B2 (riboflavin), Vitamin PP (antipellagritic), Vitamin B6 (antidermatitis), Pantothene (antidermatitis factor), Biotite (vitamin H, growth factor for fungi, yeast and bacteria, antiseborrheic), Inositol . Para-aminobenzoic acid (bacterial growth factor and pigmentation factor), Folic acid (anti-anemic vitamin, growth vitamin for chickens and bacteria), Vitamin B12 (anti-anemic vitamin), Vitamin B15 (pangamic acid), Vitamin C (anti-scorbutic), Vitamin P (permeability vitamin ).
Main feature fat-soluble vitamins is their ability to accumulate in the body, so to speak, “in reserve.” They can be stored in the body for a year and used as needed. However, too much supply fat-soluble vitamins It is dangerous for the body and can lead to undesirable consequences. Water-soluble vitamins do not accumulate in the body and, in case of excess, are easily excreted in the urine.
Along with vitamins, there are substances whose deficiency, unlike vitamins, does not lead to obvious disorders. These substances belong to the so-called vitamin-like substances:
Today there are 13 known low-molecular organic compounds that are classified as vitamins. Compounds that are not vitamins, but can serve as precursors for their formation in the body, are called provitamins. The most important provitamin is the precursor of vitamin A - beta-carotene.
The importance of vitamins very large for the human body. These nutrients support the functioning of absolutely all organs and the entire body as a whole. A lack of vitamins leads to a general deterioration in a person’s health, rather than in individual organs.
Diseases that arise due to the lack of certain vitamins in food are called avitaminosis. If a disease occurs due to the lack of several vitamins, it is called multivitaminosis. More often you have to deal with a relative lack of a vitamin; this disease is called hypovitaminosis. If the diagnosis is made in a timely manner, then vitamin deficiencies and especially hypovitaminosis can be easily cured by introducing the appropriate vitamins into the body. Excessive introduction of certain vitamins into the body can cause hypervitaminosis.
List of sources used
1. Berezov, T.T. Biological chemistry: Textbook / T.T.Berezov, B.F.Korovkin. - M.: Medicine, 2000. - 704 p.
2. Gabrielyan, O.S. Chemistry. Grade 10: Textbook (basic level) / O.S. Gabrielyan, F.N. Maskaev, S.Yu. Ponomarev, etc. - M.: Bustard. - 304 p.
3. Manuilov A.V. Basics of chemistry. Electronic textbook / A.V. Manuylov, V.I. Rodionov. [Electronic resource]. Access mode: http://www.hemi.nsu.ru/
4. Chemical encyclopedia [Electronic resource]. Access mode: http://www.xumuk.ru/encyklopedia/776.html
Vitamins play a very important role in the absorption of nutrients and in many biochemical reactions of the body. Most vitamins come from food, some of them are synthesized by the microbial flora of the intestine and absorbed into the blood, so even in the absence of such vitamins in food, the body does not need them. A lack of any vitamin in the diet (not synthesized in the intestines) causes a painful condition called hypovitaminosis. If the absorption of vitamins in the intestines is impaired due to a particular disease, hypovitaminosis can occur even with a sufficient amount of vitamins in the food.
The intake of vitamins into the body may be insufficient as a result of improper culinary processing of food: heating, canning, smoking, drying, freezing - or due to irrational one-sided nutrition. Thus, a predominantly carbohydrate diet leads to a deficiency of B vitamins; In diets containing very little protein, a deficiency of riboflavin (vitamin B2) may occur.
Many vitamins are quickly destroyed and do not accumulate in the body in the required quantities, so a person needs a constant supply of them with food. This especially applies to vitamins A, D, B1 and B2, PP and C. Here is a brief summary of the main vitamins.
Vitamin A (retinol) is of great importance for the normal functioning of the human body, as it takes part in a number of redox processes, in ensuring the function of vision, promotes the growth of children, and increases the body’s resistance to infectious diseases.
A lack of vitamin A in the body causes hypovitaminosis, the first sign of which is the so-called night blindness - visual impairment in low light (at dusk). This is due to insufficient formation of rhodopsin pigment in the retina, the synthesis of which requires vitamin A. Further development of hypovitaminosis A is manifested by dryness of the cornea and frequent infection. In addition, with a lack of retinol, degeneration of the epithelial cells of the mucous membranes of the respiratory, digestive, and urinary tracts is observed. This contributes to the development of inflammatory diseases of internal organs.
One of the characteristic signs of vitamin A deficiency is also dry skin and hair, pallor and flaking of the skin, a tendency to form acne, boils, brittle and striated nails, decreased appetite, and increased fatigue.
Not only a deficiency, but also an excess of vitamin A is harmful. Large doses of vitamin A are toxic. When more than 50 mg of retinol per day is introduced into the body for a long time, symptoms of hypervitaminosis may develop - skin itching, hair loss, general irritability, lethargy, drowsiness, headaches, as well as exacerbation of cholelithiasis and chronic pancreatitis.
Retinol is used for the prevention and treatment of infectious and colds (measles, dysentery, pneumonia, bronchitis), diseases of the digestive system (chronic gastritis, colitis, hepatitis), and some eye diseases.
Vitamin A enters the human body in finished form only with products of animal origin. The liver oil of fish (cod, sea bass, flounder, halibut) and beef liver is richest in it. It is found in smaller quantities in milk, sour cream, cream, butter, and egg yolk. Plant products contain provitamin A - carotene, which is converted into vitamin A in the wall of the small intestine and in the liver. Vegetables and herbs are the source of carotene; carrots, pumpkin, parsley, red pepper, dill, tomatoes, sorrel, spinach, green onions, as well as fruits and berries - apricots, tangerines, oranges, lemons, peaches, rowan, rose hips, apricots, raspberries, black currants. For better absorption of carotene, the corresponding food products should be consumed in combination with vegetable oil or sour cream.
The daily physiological requirement for vitamin A for a healthy person is 1.5 mg, for carotene - 3 mg.
Vitamin B1 (thiamine) plays an important role in the regulation of carbohydrate, fat, mineral and water metabolism. It has a beneficial effect on cellular respiration, nervous and cardiovascular systems, and digestive organs. In the human body, thiamine is formed in the intestines, but in insufficient quantities, so it is necessary to additionally introduce it with food.
If there is a lack of vitamin B1 in food, the oxidation of carbohydrates does not reach completion, and intermediate products - pyruvic and lactic acids - accumulate in the tissues, as a result of which the processes of transmission of nerve impulses are disrupted.
Mild hypovitaminosis B1 leads to dysfunction of the central nervous system in the form of mental depression, general malaise, increased fatigue, headache, insomnia, and decreased attention.
A significant deficiency of vitamin B1 in the body leads to the development of a serious disease called beriberi. It is accompanied by polyneuritis, sensitivity disorders of the limbs, cardiac disturbances (palpitations, cardiac weakness), and a decrease in the body's resistance to infections.
The daily requirement for vitamin B1 is 2 mg. The need for thiamine increases with a high content of carbohydrates in food, as well as during febrile conditions, intestinal diseases, increased function of the thyroid gland (thyrotoxicosis), neuritis and radiculitis.
Vitamin B1 is found in rye bread, buckwheat and oatmeal, liver and kidneys of cattle and pigs, and ham. The best sources of thiamine are whole grains of various cereals, legumes and nuts (peanuts, hazelnuts, walnuts). To prevent thiamine deficiency, it is recommended to consume yeast drinks and bread kvass, as well as pre-soaked wheat and rye grains.
Vitamin B2 (riboflavin) has a significant effect on visual function - increases the sharpness of color discrimination and improves night vision. This vitamin is part of a number of enzymes involved in the metabolism of carbohydrates, the synthesis of proteins and fats.
Riboflavin obtained from food combines with phosphoric acid in the body (phosphorylated). Together with proteins, this acid is part of the enzymes necessary for cellular respiration. Vitamin B2 has a regulating effect on the functions of the central nervous system and liver, stimulates the formation of red blood cells.
If there is insufficiency of riboflavin in the body, protein synthesis deteriorates, the oxidation of lactic acid is disrupted, glycogen disappears from the liver, the formation of amino acids is inhibited, and cardiac and circulatory disorders develop. Characteristic signs of riboflavin deficiency are cracks in the corners of the mouth. Further development of hypovitaminosis causes loss of appetite, weight loss, weakness, apathy, headaches, burning sensation of the skin, itching or pain in the eyes, impaired twilight vision, conjunctivitis. Cracked breast nipples in nursing women may be a consequence of a lack of vitamin B2, since during lactation the body's need for this vitamin increases significantly.
The average daily human need for riboflavin is 2.5-3 mg.
The most important sources of riboflavin: whole milk, especially curdled milk, acidophilus, kefir, cheese, lean meat, liver, kidneys, heart, egg yolk, mushrooms, baker's and brewer's yeast. Vitamin B2 is stable during cooking.
Vitamin B5 (pantothenic acid) is an integral part of many enzymes involved in protein, carbohydrate and fat metabolism, stimulates the formation of hormones of the adrenal cortex.
The richest foods in pantothenic acid are liver, kidneys, egg yolk, lean meat, milk, fish, peas, wheat bran and yeast. During cooking, up to 25% of vitamin B5 is lost. It is produced in sufficient quantities by microbes living in the colon, so there is usually no shortage of pantothenic acid (the need for it is 10-12 mg per day).
Vitamin B6 (pyridoxine) is part of numerous enzymes involved in the metabolism of amino acids, unsaturated fatty acids, and cholesterol. Pyridoxine improves fat metabolism in atherosclerosis. Vitamin B6 has been found to increase urination and enhance the effect of diuretics.
Severe vitamin B6 deficiency is rare, since it is produced by microbes in the intestines. Sometimes it is observed in young children fed with autoclaved milk. This is expressed in growth retardation, gastrointestinal disorders, increased nervous excitability, and convulsive attacks.
The average daily dose of pyridoxine is 2-2.5 mg. It is found in plants, especially in unrefined cereal grains (wheat, rye), in vegetables, meat, fish, milk, in cattle liver, egg yolk, and relatively high amounts of vitamin B6 in yeast. This vitamin is heat stable but degrades when exposed to light (especially ultraviolet rays).
Vitamin B12 (cyanocobalamin) has a complex structure, its molecules contain a cobalt atom and a cyano group.
In the human body, this vitamin is necessary for the formation of nucleic acids and some amino acids (choline). Vitamin B12 has high biological activity. It stimulates growth, normal hematopoiesis and maturation of red blood cells, normalizes liver function and the state of the nervous system. In addition, it activates the blood coagulation system (increases the activity of prothrombin), has a beneficial effect on the metabolism of carbohydrates and fats - in atherosclerosis, it lowers cholesterol in the blood, increases the amount of lecithin, and has a pronounced ability to reduce fat deposits in internal organs.
Vitamin B12 deficiency occurs most often in connection with diseases of the stomach or intestines, as a result of which the extraction and absorption of vitamin B12 contained in food is impaired, which manifests itself in the form of severe anemia due to disruption of normal hematopoiesis in the bone marrow.
In the human body, vitamin B12 is formed in the intestines in small quantities; in addition, it comes from products of animal origin. Vitamin B12 is found in liver, meat, eggs, fish, yeast, as well as in medicinal preparations obtained from animal liver. An important source of it is milk, especially sour milk, since it is synthesized by some lactic acid bacteria. It is heat resistant but sensitive to light.
Vitamin B9 (folic acid) is an integral part of the B vitamin complex. Together with vitamin B12, folic acid is involved in the regulation of hematopoiesis, the formation of red blood cells, leukocytes and platelets, as well as in the regulation of protein metabolism, stimulates growth, and reduces fat deposition in internal organs.
Folic acid is found in fresh vegetables and herbs - tomatoes, beans, carrots, cauliflower, spinach, green leaves of parsley, celery, as well as in the liver, kidneys, and brains of animals. During culinary processing of food, due to the instability of folic acid to heat, its loss reaches 50-90%. In the human intestine it is synthesized by microflora in sufficient quantities to meet the body's needs.
In this regard, the corresponding vitamin deficiency can occur only as an exception. Hypovitaminosis develops when large doses of sulfonamides or antibiotics are administered, which destroy the intestinal microflora and thereby block the formation of folic acid. Vitamin deficiency can also occur when folic acid absorption is impaired due to diseases of the small intestine. Since vitamin B12 is required for the absorption of folic acid, if it is deficient, the absorption of folic acid is impaired. The estimated daily human need for folic acid is 0.2-0.3 mg.
Vitamin B15 (calcium pangamate) improves fat metabolism, increases the absorption of oxygen by tissues, increases the content of energy-rich substances (creatine phosphate and glycogen) in the heart, skeletal muscles and liver. Vitamin B15 is found in plant seeds (in Greek “pan” - everywhere, “gam” - seed), brewer’s yeast, rice bran, liver. It is widely used in the treatment of heart and liver diseases.
Vitamin B17 (nitriloside) opened relatively recently. It improves metabolic processes and prevents the development of tumors. It is found in large quantities in fruits, especially in cereals (rye, wheat) and seeds - the seeds of apples, pears, and grapes.
Vitamin C (ascorbic acid)- one of the most important vitamins in the human diet. The physiological significance of ascorbic acid in the body is very diverse,
Ascorbic acid activates a number of enzymes, promotes better absorption of iron and thereby enhances! hemoglobin formation and red blood cell maturation. Vitamin C stimulates the formation of a very important protein - collagen. This protein binds individual cells into a single tissue. With its deficiency, wound healing is greatly slowed down. Ascorbic acid affects the synthesis of another protein, the deficiency of which causes a violation of the plasticity and permeability of blood vessels, resulting in numerous hemorrhages and bleeding gums.
Vitamin C has a pronounced antitoxic effect against many toxic substances. Thus, the neutralizing effect of ascorbic acid on diphtheria, tuberculosis, dysentery and other microbial poisons has been established.
Ascorbic acid has another extremely important ability. It increases the body’s natural immunobiological resistance to infectious and colds, and has a pronounced effect on the activity of macrophages, which capture and digest pathogenic microbes that have entered the body.
Currently, vitamin C is widely used in medical practice in the treatment of many diseases.
Improper thermal conditions for food processing and long-term storage of finished food products cause oxidation and loss of large quantities of ascorbic acid. Hypovitaminosis C can occur with diseases of the gastrointestinal tract that impair the absorption of ascorbic acid (for example, this is observed in chronic hypacid gastritis, enterocolitis), as well as with a lack of vitamins B1 and B2 and after long-term use of certain medications, such as salicylates and sulfonamide drugs.
Long-term vitamin C deficiency, depending on its severity, can cause the development of scurvy, which is characterized by damage to blood vessels, especially capillaries. This is expressed in increased permeability and fragility of capillary walls. Bleeding capillaries leads to hemorrhages in the skin, muscles, and joints. At the same time, the gums become inflamed, teeth become loose and fall out, anemia develops, and blood pressure decreases. Lips, nose, ears, nails become bluish. Pain in the bones and joints, general lethargy, fatigue, pale skin appear, body temperature drops, and resistance to various diseases, mainly of the gastrointestinal tract and respiratory system, decreases.
The daily requirement of an adult for vitamin C is 70-100 mg. This standard increases for people working in hot shops, living in hot climates or the Far North, as well as for people engaged in heavy physical labor and sports. Pregnant and breastfeeding women need double the normal amount of vitamin C. An increased amount of ascorbic acid is necessary for older people, as this vitamin has the ability to prevent the development of atherosclerosis.
Vitamin C is not produced in the human body, so a constant supply of it through food is necessary.
The richest sources of ascorbic acid are green parts of plants, most vegetables and fruits. There is especially a lot of vitamin C in rose hips, chokeberries, black currants, lemons and unripe walnuts. Potatoes contain the most vitamin C in the fall; in December, its amount decreases by half, and in March - by 4 times.
In addition to ascorbic acid, rose hips contain vitamins B2, P, K and carotene (provitamin A). Rose hips are distinguished by the fact that they do not contain the enzyme ascorbinase, which destroys ascorbic acid. Therefore, in mature rose hips, the process of destruction of vitamin C is much slower than in plants containing ascorbinase. Dried rose hips can retain their vitamin activity for several years. Ascorbinase is also absent in lemon, orange, and black currant.
The richest fruits in vitamin C are rose hips, which have an orange color and protruding remains of sepals; in low-vitamin rosehip species, the remains of the sepals are tightly pressed to the walls of the fruit. There is a lot of vitamin C in sprouted grains of rye, wheat, and peas.
When cooking food products, about 50-60% of ascorbic acid is lost. To ensure that vitamin C is destroyed as little as possible by exposure to atmospheric oxygen, food should be cooked in a non-oxidizing (enamel) container, covered, not overcooked and not stored for a long time, since when ready-made dishes are reheated, the loss of vitamin C quickly increases. From this point of view, raw vegetables, fruits and berries are of greatest value.
Vitamins of group D participate in the exchange of calcium and phosphorus: activate the absorption of calcium from the digestive tract, as well as the deposition of calcium in bone tissue and dentin; stimulate the exchange of phosphoric acid, which plays an important role in the activity of the central nervous system and the general energy of the body. In addition, vitamin D stimulates growth and affects the functional state of the thyroid, goiter, parathyroid and gonads. A large amount of vitamin D is found in the liver of sea fish (together with vitamin A), slightly less in butter, milk, egg yolk, and fish roe. In plants, vitamin D is in a biologically inactive form. Yeast is especially rich in it. In foods of animal origin, vitamin D is also biologically inactive; conversion to the active form occurs in the skin under the influence of sunlight or artificial irradiation with ultraviolet rays. Therefore, in the autumn-winter period, irradiation with a quartz lamp is recommended. Fortified fish oil is also used as a source of vitamin D. If there is a lack of vitamin D in the child’s body, rickets develops, in which ossification processes are disrupted (bones become soft, the structure of the teeth changes). Similar changes can occur in the body of pregnant and lactating women, whose need for vitamin D is sharply increased.
Excessive consumption of vitamin D has a toxic effect on the human body - it promotes the development of atherosclerosis, leads to calcium deposition in internal organs, and digestive disorders.
The daily requirement of vitamin D for children, pregnant women and nursing mothers is 500 international units (IU). Medical fish oil, sold in pharmacies, contains about 1000 IU per teaspoon.
Vitamin P found in citrus fruits, rose hips, black currant berries, red bell pepper.
The biological effect of vitamin P dough is associated with the presence of ascorbic acid. It promotes the absorption of vitamin C and protects it from oxidation. Therefore, in the presence of vitamin P, the need for ascorbic acid is reduced.
Food plants rich in vitamin C always contain vitamin P. This explains the greater effectiveness of vitamin C contained in plant products compared to synthetic preparations.
With a lack of vitamin P, capillaries become fragile, their fragility increases, and pinpoint hemorrhages appear.
Two preparations of vitamin P are used: from tea tree leaves and from the green mass of buckwheat rutin. The daily requirement of a healthy adult for vitamin P is 35-50 mg.
Vitamin K has the ability to increase blood clotting. With hypovitaminosis K, along with a decrease in blood clotting, the strength of capillaries decreases, which can only be restored by systematically taking vitamin K. The use of vitamin P in these cases does not have an effect, just as the administration of vitamin K does not help with vitamin P deficiency.
Vitamin K accelerates wound healing and has an analgesic effect. Its antibacterial effect has also been noted.
Vitamin K is synthesized by bacteria in the large intestine. Hypovitaminosis K can occur when absorption processes in the colon are disrupted, as well as due to diseases of the liver and biliary tract, since the presence of bile acids is necessary for the absorption of vitamin K.
The daily requirement of an adult for vitamin K is approximately 1-2 mg. Vitamin K is found in green lettuce, spinach, white and cauliflower, as well as carrots, tomatoes, and rowan berries. Natural vitamin K is resistant to high temperatures, insoluble in water, and highly soluble in fats.
Vitamin PP (nicotinic acid) is part of a number of enzyme systems in the body that control tissue respiration. Vitamin PP is involved in the regulation of carbohydrate, protein and water-salt metabolism, and normalizes cholesterol levels in the blood.
Nicotinic acid tends to expand the lumen of capillaries and arterioles, as a result of which vascular spasms may disappear. Vitamin PP increases the acidity of gastric juice, regulates the motor activity of the stomach, promotes better absorption and assimilation of nutrients, and has a positive effect on liver function.
A lack of nicotinic acid in food disrupts the formation of enzymes that carry out redox reactions and cellular respiration. The lack of vitamin PP in food leads to a serious disease - pellagra (from the Italian word “pella agra” - rough skin). Patients with pellagra develop pigmentation, peeling and ulceration of the skin on exposed areas of the body exposed to sunlight, and intestinal function is impaired. In severe cases, mental disorders with visual and auditory hallucinations are observed.
Since vitamin PP is quite widespread in nature, pellagra is extremely rare with a normal mixed diet. In the human body, this vitamin is synthesized from the amino acid tryptophan. This is the most stable vitamin; it is preserved during prolonged boiling and drying, and does not change when exposed to light and oxygen. The best sources of niacin are yeast, liver, lean meat; legumes, buckwheat, potatoes, and nuts are rich in it. The daily requirement of an adult for vitamin PP is 15-20 mg, for pregnant and lactating women - 20-25 mg, for children - 5-15 mg.
Vitamin E necessary for the normal course of pregnancy and feeding of offspring. The most important symptom of vitamin E deficiency in a woman’s body is the loss of the ability to bear a fetus normally: pregnancy is interrupted by spontaneous miscarriage.
With experimental E-vitaminosis in male rats, sperm formation is disrupted: sperm without flagella appear, losing the ability to move and fertilize. Then sperm production stops, the sexual instinct fades, the reverse development of external sexual characteristics occurs, and the males resemble castrated animals. They experience degenerative changes in the skeletal muscles and cardiac muscle, and the activity of the nervous system and liver is disrupted.
Another very important property of vitamin E should be noted: it is an excellent physiological antioxidant (antioxidant). This is of great importance for the prevention of premature aging, since it is assumed that one of the causes of aging is clogging of intercellular spaces with oxidation products. Vitamin E stops this process.
Vitamin E is highly resistant to heat and is not destroyed under normal cooking conditions. It is found in plant products, especially vegetable oils (sunflower, corn, cottonseed, flaxseed), rose hips, egg yolks, peas, beans, lentils, as well as rye and wheat grains. The daily dose of vitamin E is 20-30 mg.
It has a beneficial effect on nervous tissue and is involved in carbohydrate and fat metabolism. Biotin deficiency manifests itself in humans as seborrheic dermatitis.
Biotin is found in egg yolk, liver, kidneys, yeast, cereal grains and legumes, and fresh vegetables. Resistant to high temperatures. The daily requirement for biotin is approximately determined at 0.15-0.2 mg.
Classmates
Joke:
I was riding on the bus, all in tears because of unhappy love.
The little boy looked at me and said:
- You're crying because you're fat, right?
Vitamins(lat. vita- life) is a group of low molecular weight organic compounds necessary for the normal functioning of a heterotrophic organism.
Vitamins do not include microelements and essential amino acids.
History of the discovery of vitamins
Until the 19th century, nothing was known about the existence of vitamins, although people periodically encountered symptoms of vitamin deficiency. Usually the causes of the painful condition were attributed to infection.
Sailors especially suffered from vitamin deficiency. Many vitamins are found in vegetables and fruits, which are perishable foods. Therefore, they were usually not taken on expeditions. As a result, travelers suffered and often died from vitamin deficiencies.
It is known that Scottish physician James Lind was one of the first to suggest using citrus fruits to treat scurvy in sailors in 1747.
Rice. James Lind and his work
James Cook introduced sauerkraut, malt wort and a kind of citrus syrup into the ship's diet. As a result, on the journey Not a single sailor died from scurvy. In 1795, lemons and other citrus fruits became a standard addition to the diet of British sailors.
In 1880, a Soviet pediatricianNikolai Ivanovich Lunin experimentally proved that “...milk, in addition to casein, fat, milk sugar and salts, contains other substances that are essential for nutrition. It is of great interest to study these substances and study their importance for nutrition.”
Lunin conducted experiments on mice. Two groups of mice were taken. Some were fed “artificial milk,” which consisted exclusively of casein (milk protein), fat, milk sugar, mineral salts and water. Mice feeding on this milk soon began to lose weight and died. Mice from another group, which were given natural milk as food, grew healthy and strong.
Rice. N. I. Lunin and his experiment
beriberi research
In the 17th century, the countries of Southeast and South Asia learned to polish rice, which improved its taste. However, it was then that a new disease appeared, called “beriberi.” The symptom of the disease was extreme weakness leading to paralysis and death. At that time, it was decided that the epidemic was caused by contaminated rice. This disease was mainly typical for residents of Japan and Southeast Asia.
Rice. Take-take from a person Fig. Take-take from pigeons (a - disease, b - normal)
Only in 1886, the Dutch doctor and bacteriologist Christian Eijkman, who studied beriberi in a prison hospital on the island of Java, experimentally proved that Rice husks contain a substance that can prevent beriberi (polyneuritis).The scientist isolated this compound from rice husks.
Eijkman used chickens for his experiments. In one experiment, he discovered that chickens fed polished rice developed polyneuritis - very similar to human beriberi. When the experimental animals were switched to brown rice, they recovered.
Research conducted by Christian Eijkman laid the foundation for a method of treating diseases associated with a lack of certain substances in food.
Frederick Hopkins called these essential substances "additional factors" and studied them further. During experiments, Hopkins and his colleagues found that milk protein (casein) contains a substance necessary for the growth and development of the body.
In 1929, Aickman and Hopkins were awarded the Nobel Prize for their contributions to the discovery of vitamins.
Rice. Christian Eijkman Fig. Frederick Hopkins
1912 - Polish chemist Casimir Funk coined the term “vitamin”. Funk determined the chemical composition of a substance isolated from rice bran, and, having discovered an amino group in it, named it “vitamin”: from the Latin words “vita” (life) and “amine” (nitrogen). And although not all vitamins contain nitrogen, this term has been preserved.
1916 - vitamin A: a substance that stimulates growth;
1935 - vitamin K (koagulations vitamin) (Danish chemist Henrik Dam, Nobel Prize in 1943;
1936 -- thiamine (vitamin B1);
1936 - the first vitamin E preparations were obtained by extracting grain sprouts from oils.
1938 - German chemist Richard Kuhn determined the formula and synthesized flavin (vitamin $B_2$), a substance “necessary for nutrition” (cited by Lunin), contained in milk.
The role of vitamins in the human body
Vitamins do not have significant plastic and energy value for the human body.
The body is unable to synthesize most vitamins on its own. These vitamins should be an integral part of the human diet. Sources of vitamins for humans are food products of plant and animal origin. Vitamins come with food in finished form or in the form provitamins, from which vitamins are formed in the body. Some vitamins are synthesized by intestinal microflora.
Vitamins are divided into:
- fat soluble vitamins: A, D, E, K;
- water soluble vitamins: C, P and B vitamins.
Fat-soluble vitamins accumulate in adipose tissue and the liver.
Water-soluble vitamins do not accumulate in the body; if they are in excess, they are excreted with water. Therefore, hypovitaminosis is more common water-soluble vitamins and hypervitaminosis of fat-soluble vitamins.
Most vitamins are coenzymes(structural units of enzymes) or their precursors. Therefore, many vitamin deficiencies can be considered as pathological conditions that arise due to loss of functions of certain coenzymes. However, at present, the mechanism of occurrence of many vitamin deficiencies is still unclear.
Interestingly, pharmaceutical antibiotics (for example, from the sulfonamide group) resemble in their chemical characteristics the vitamins necessary for bacteria. Such substances “disguised as vitamins” are captured by bacteria, while the active centers of the bacterial cell are blocked, its metabolism is disrupted, and the death of the bacteria occurs.
Vitaminology- medical and biological science that studies the structure and mechanisms of action of vitamins, as well as their use for therapeutic and preventive purposes.
Free radical oxidation processes can occur in the cell, when oxygen is directly added to the oxidized substances. It is carried out without the help of enzymes and is destructive in nature. Therefore, the body needs antioxidants- substances that prevent free radical oxidation of substances. Vitamins C, E, P bind free radicals, preventing the formation of toxic compounds.
When there is a deficiency or excess in the body of any vitamin, a pathological condition occurs, characterized by a certain set of symptoms. (syndrome).
Hypovitaminosis- a pathological condition associated with a lack of a certain vitamin in the body.
Avitaminosis- a severe pathological condition associated with the lack of a certain vitamin in the body.
Hypervitaminosis- a pathological condition associated with an excess of a certain vitamin in the body.
The availability of some vitamins depends on their intake from food (essential vitamins). They come in finished form, or in the form of provitamins, which are converted into vitamins during metabolism.
Water-soluble vitamins:
B vitamins- are part of many enzymes; contained in products; some are synthesized by intestinal symbionts;
vitamin C, or ascorbic acid- necessary for the normal formation of connective tissue; comes with food; with its deficiency, scurvy develops;
vitamin K- blood clotting factor; formed by intestinal symbionts;
Fat-soluble vitamins:
vitamin A(retinol) - necessary for the formation of visual pigment - rhodopsin, with its deficiency, visual impairment develops; enters the body with food of animal origin or is synthesized in the body from the provitamin vitamin A - carotene, contained in red-orange fruits and root vegetables;
vitamin D- participates in the mineralization of bone tissue, its active form is formed in the body during ultraviolet irradiation, therefore the disease associated with it - rickets- can develop with a lack of the vitamin itself or with a lack of ultraviolet radiation in winter in the northern regions.
vitamin E(tocopherol) - participates in reproductive function and immune defense; comes with food;
Avitaminosis and hypovitaminosis can occur not only in the absence of vitamins in food, but also when their absorption is impaired due to diseases of the gastrointestinal tract. The state of hypovitaminosis can also occur with the usual intake of vitamins from food, but with increased consumption (during pregnancy, intensive growth), as well as in the case of suppression of intestinal microflora by antibiotics.
| Vitamin |
The importance of vitamin in the human body |
Foods with the highest content of this vitamin |
Vitamin intake rate (mg/day) |
Hypovitaminosis/vitaminosis* |
| A |
growth and development, epithelial restoration, vision; synthesis of sex hormones; immunity (synthesisinterferons, immunoglobulin, lysozyme); antioxidant |
liver, butter, egg yolk, yellow-orange vegetables and fruits; can be synthesized in the body from provitamins - carotenoids |
700 mcg/day. (for women), 900 mcg/day. (for men) | night blindness |
| metabolism of fats and carbohydrates, growth and development; work of the heart, nervous and digestive systems; participates in energy metabolism (NAD supplier) | wheat bread from wholemeal flour, soy, beans, peas, spinach, meat, yeast | 1.1 - 1.2 mg/day. | take it | |
| $B_2$ (riboflavin) | formation of red blood cells, antibodies, regulation of growth and reproductive functions; thyroid function, skin health and its derivatives | liver, kidneys, yeast, eggs, almonds, cabbage, mushrooms, milk | 1.8 - 2.0 mg/day. | cracks in the mucous membrane lips, tongue, dermatitis of eyelids, ears, nose |
|
(a nicotinic acid) |
energy metabolism; synthesis of proteins and fats |
rye bread, pineapple, beets, buckwheat, beans, meat and offal, mushrooms and other protein foods; can be synthesized in the body from tryptophan. Synthesized by bacterial symbionts in the large intestine |
15 - 19 mg/day |
pellagra; night blindness |
| $B_4$ (choline) | acetylcholine synthesis, insulin synthesis, fat metabolism; nervous system function, memory | egg yolk, brain, liver, kidneys, heart; cabbage, spinach, soy, mushrooms | 450 - 550 mg/day. | liver and nervous system diseases |
| $B_5$ (pantothenic acid) | is part of coenzyme A, which is involved in plastic metabolism; regulates the functioning of the adrenal glands, participates in the synthesis of antibodies | yeast, fish roe, nuts, egg yolk, green parts of plants, milk, carrots, cabbage, offal | joint pain, hair loss, limb cramps, paralysis, weakened vision and memory | |
| $B_6$ (pyridoxine) | metabolism stimulator, protein metabolism; participates in the production of hemoglobin; supplying cells with glucose |
grains, legumes, fish, liver, wheat, meat and dairy products, eggs. Synthesized by intestinal microflora. |
increased fatigue; depression; hair loss; cracks in the corners of the mouth; circulatory disorders; numbness of the limbs; arthritis; muscle weakness | |
|
regulates metabolism (including blood sugar levels); is a source of sulfur, which takes part in collagen synthesis |
in liver, kidneys, yeast, legumes (soybeans, peanuts), cauliflower, nuts; healthy intestinal microflora synthesizes biotin in sufficient quantities for the body |
50 mcg/day | skin and hair damage; anemia, depression, weakness, high cholesterol and blood sugar | |
| $B_(12)$ | plastic and energy metabolism (oxidation of proteins and fats) |
liver, kidneys, milk, any products animal origin, including fish and shellfish. It is produced in the large intestine of animals, but is absorbed only in the small intestine and accumulates in the liver and kidneys. |
2.4 mcg/day. | anemia, death of nerve cells |
| C (ascorbic acid) | antioxidant, synthesis of neurotransmitters (serotonin), thyroid hormones, collagen, stimulates interferon synthesis and energy metabolism | rose hips, kiwi, cabbage, raw potatoes, red peppers, currants, cranberries, citrus fruits | scurvy | |
| D | regulation of phosphorus and calcium metabolism |
$D_3$ formed in human skin under the influence of ultraviolet light, $D_2$ comes from food (liver, fish, eggs, butter, cheese, yeast) |
15 mcg/day. | rickets, osteoporosis |
| E | mammalian reproduction, immunomodulator and antioxidant | vegetable oils | muscular dystrophy, infertility, liver and brain destruction | |
| TO | blood clotting, metabolism in bone and connective tissue, kidney function |
green leafy vegetables, cabbage, bran, avocado, kiwi, meat and dairy products. Synthesized by bacterial symbionts in the large intestine. |
90 mcg/day. | internal bleeding, bone deformation |
| R (rutin) | increases blood viscosity, in combination with vitamin C increases the strength of vascular walls | rose hips, citrus fruits, unripe walnuts, currants, rowan, green tea, buckwheat | 60 mg/day. | hemorrhages, fatigue, muscle pain, hair loss, bluish skin tone, acne |
| participates in energy metabolism (NAD supplier) | rye bread, pineapple, beets, buckwheat, beans, meat and offal, mushrooms; can be synthesized in the body from tryptophan. Synthesized bacterial symbionts in the large intestine. | 15 - 20 mg |
pellagra; night blindness |
*Brief comments on the names of diseases.
Take it- weakness, weight loss, muscle atrophy, intellectual impairment, disorders of the digestive and cardiovascular systems, development of paresis and paralysis.
Night blindness- twilight vision disorder.
Scurvy- violation of collagen synthesis - loss of connective tissue strength - bleeding (including bleeding gums, nasal bleeding).
Pellagra- a disease caused by a lack of vitamin PP, accompanied by dermatitis, diarrhea, dementia(dementia).
Rickets- a disease of infants and young children caused by a lack of vitamin D, and, as a consequence, a violation of calcium metabolism, calcium deficiency andoccurring with impaired bone formation and insufficient mineralization.
Rice. Rickets (in a child: large belly, irregular skull, curvature of leg bones)
Osteoporosis- a disease associated with impaired bone formation and increased bone fragility; may be due to vitamin D deficiency.
Translated from Latin, the word vitamins means “life.” Therefore, the importance and necessity of these elements for the human body, and indeed any living creature, for the normal development and functioning of all life support systems is clear.
There is a whole science called vitaminology, together with biochemistry and pharmacology, which studies the properties of individual vitamins and entire complexes, their influence on living organisms, determining methods of their production and rules of administration in individual therapeutic and preventive cases.
Simple food consumed by humans contains very small amounts of vitamins and microelements necessary for the body. And they are in such a state that the enzymes of the digestive system cannot completely absorb and process them. Although they do not contain calories and are not a source of energy for the body, they are nevertheless very important for proper metabolism and the prevention of such serious diseases as scurvy and vitamin deficiency. Currently, scientists have identified 13 substances recognized as essential vitamins for the human body. It is difficult to list the names of all vitamins and their components in one article. The most significant elements for a normal and healthy human life are:
Vitamin B5 and B6. A lack of these vitamins causes joint pain, hair loss and weakened vision and memory.
Vitamin C – ascorbic acid. A lack of this vitamin leads to bleeding gums and even scurvy.
Vitamin D. When this vitamin is reduced, a dangerous disease such as rickets develops.
Vitamin A. Symptoms of a lack of this substance in the body are night blindness, dryness and redness of the eyes.
The body can synthesize some vitamins on its own, for example, vitamin D is formed in the human skin under the influence of solar ultraviolet radiation. The bulk of vitamins should be supplied to the body through food. Therefore, it is extremely important for every person, especially those weakened by illness or after the winter season, to monitor a proper and balanced diet. The role of proper intake of vitamin complexes in the prevention and treatment of body diseases is also great. But independent and uncontrolled use of these substances, without consulting a doctor, can cause irreparable harm to a person.
Option 2
The human body is a well-coordinated mechanism that, in order to work successfully without interruption, needs various nourishments in the form of food, water and microelements, which can also be called vitamins. Vitamins means “life” in Latin. These are organic compounds of microelements that are necessary for any organism. They are able to influence certain processes.
Vitamins can be found in food, the surrounding atmosphere, plants, fruits and the like. It is important to note that food products contain vitamins to a lesser extent. In fact, there is no exact definition of vitamins. There are currently 13 known vitamins. All of them are studied by the special science of vitaminology. She examines the use of vitamins in pharmaceutical preparations for the treatment and prevention of disease.
Vitamins perform a special function as a catalyst within active substances, enzymes. They also regulate the content of hormones in the body or their replacement. Vitamins play an important role in metabolism, since they do not provide direct energy due to the lack of calories and do not represent a structural component of cell tissue. According to research, the content of vitamins does not particularly affect the functioning, structure and external processes of the body, but if they are deficient, serious consequences arise. These may be diseases: scurvy - a lack of vitamin C, which leads to tissue fragility. Avitaminosis is an inadequate content of any vitamins. In addition to deficiency, there may be an excess of vitamins, this disease is called hypovitaminosis.
All vitamins are divided into two groups: those that cannot be synthesized are those that must enter the body only through food. And the smallest group is synthesized, which are independently formed under the skin due to sunlight.
Vitamins can be called only those elements that are organic substances, the absence of which can lead to diseases, the body is not able to produce on its own and which every person needs to consume daily. Vitamins are an invisible but important part of a person’s life, without which he cannot exist.
Gzhel is a type of folk painting of dishes. This type of art originated in the Gzhel region, consisting of many villages. It was in his honor that such a painting was named. The area is not far from the Moscow region.
The widespread birch tree grows up to 30-40 meters. It has a large crown, which is rich green in summer, and with the arrival of autumn changes color to golden.
