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Vitamins in the diet and healthy eating.

The biological effect of vitamins in the human body is the active participation of these substances in metabolic processes.

In the metabolism of proteins, fats and carbohydrates, the vitamins take part either directly or as part of complex enzyme systems. Vitamins are involved in oxidative processesSakha, which resulted from the carbohydrates and fats formed numerous substances used by the body as an energy and plastic material.

An important role is played by vitamins in maintaining the immunobiological reactions of the body, ensuring its resistance to adverse environmental factors, which is essential in the prevention of infectious diseases and when exposed to adverse environmental factors. Vitamins soften or eliminate the adverse effect on the human body of many drugs.

Some vitamins are not synthesized in the human body and must come from food. A person's need for vitamins is very small (expressed in milligrams and even micrograms per day). However, with the prolonged absence of one or another vitamin in food, serious diseases develop (scurvy, pellagra, etc.), called avitaminosis. In our country, as a result of improving the well-being of people and improving nutrition, vitamin deficiencies are not found.

If an insufficient amount of any vitamin enters the body, hypovitaminosis develops; with a deficiency of several vitamins - polyhypovitaminosis. Vitamin deficiencies in the body can be primary - as a result of insufficient intake from food, and secondary - due to impaired digestion in diseases of the digestive system, increasing the need for vitamins in certain physiological conditions, such as pregnancy, infectious diseases and other diseases.

Lack of vitamins in the body can also occur due to the irrational ratio of individual components of the diet, in particular, with an excess of carbohydrates, a limited amount of fat or protein deficiency, with improper culinary processing of food and long-term storage of ready-made food.

Secondary vitamin deficiency can develop when exposed to various environmental factors. Thus, at low ambient temperatures, the body’s need for vitamins rises dramatically. It also increases during a stay in high temperature conditions, since vitamins are excreted in sweat. Especially increases the need for vitamins with a combination of high ambient temperatures with significant ultraviolet radiation, which, as a rule, have a rest in the south. Exercise and physical stress lead to increased consumption of vitamins.

Hypovitaminosis is manifested primarily by deterioration of efficiency, general weakness, reduced body resistance to infectious and catarrhal diseases, decreased visual acuity in the dark, etc. At the first signs of hypovitaminosis, you should consult a doctor, as you can treat yourself with vitamins, especially retinol (vitamin A), and ergoCalciferol (vitamin E), can lead to the opposite state - hypervitaminosis.

Currently, several dozens of vitamins and vitamin-like compounds have been discovered, of which 20 has been well studied. Previously, vitamins were designated by the letters of the Latin alphabet. However, with the refinement of the chemical structure of each of them and the biochemical function in the body, terminology was adopted, reflecting these features of vitamins.

Depending on the ability to dissolve vitamins are divided into two groups: water soluble and lipid soluble. The following is the modern classification of vitamins.

Classification of vitamins

Water-soluble vitamins

Thiamine (vitamin B) regulates protein, fat, carbohydrate and mineral exchanges, the activity of the circulatory and digestive organs, and the function of the nervous system. The daily requirement of adult healthy people for thiamine is 1,3 — 2,6 mg.

Thiamine-rich bread and bakery products from wholemeal flour (0,21 mg / 100 g), buckwheat (0,53 mg / 100 g), oatmeal (0,49 mg / 100 g) and millet (0,62 mg / 100 g) cereals, soybeans (0,94) mg / 100 g), peas (0,81 mg / 100 g), beans (0,5 mg / 100 g), lean pork (0,52 mg / 100 g), beef liver (0,3 mg / 100 g). A large amount of thiamin is found in yeast.

Thiamine deficiency in the body can occur when bread is consumed mainly from fine flour. Excess carbohydrates in the diet, alcohol consumption also contribute to the development of thiamine deficiency. However, the most common cause of hypovitaminosis B] are diseases of the digestive system (enteritis, colitis), which is associated withsheniem vitamin intake. If hypovitaminosis In! especially marked headache, irritability, memory loss, loss of appetite. Later, there is a pain in the heart, palpitations, nausea, abdominal pain, constipation, sometimes diarrhea.

 

I. The water-soluble vitamins

II. Fat-soluble vitamins

Ascorbic Acid (Vitamin C)

Calciferol (vitamin D)

Retinol (vitamin A)

Biotin (vitamin H)

Tokoferolы (vitamin E)

Bioflavonoidы (vitamin P)

Phylloquinone (vitamin K)

Nykotynovaya acid, niacin (Vitamin PP)

III. vitamin-like compound

Pantothenic Acid (Vitamin B3)

Vitamin and Inositol

Carnitine

Pyridoxine (vitamin B6)

lipoic acid

Riboflavin (vitamin B2)

orotic acid

Thiamine (vitamin C1)

Pangamic acid (vitamin b15)

P-aminobenzoic acid

Folic acid (folacin)

Cyanocobalamin (Vitamin B12)

Mixed

 

Riboflavin (vitamin B2) is involved in the metabolism of proteins, fats and carbohydrates. It improves visual acuity, positively affects the functions of the digestive organs, blood formation, regulates the activity of the central nervous system. The need for adults in riboflavin is 1,5 — 3 mg per day.

The main sources of this vitamin are beef liver (2,19 mg / 100 g), milk (0,13 mg / 100 g), eggs (0,44 mg / 100 g), meat (0,14 — 0,23 mg / 100 g), fish (0,11 — 0,2 mg / 100 g), buckwheat (0,2 mg / 100 g) and oat (0,11 mg / 100 g) cereals, peas (0,15 mg / 100 g), beans (0,18 mg / 100 g), wholemeal bread (0,11— 0,12 mg / 100 g). A lot of riboflavin in yeast.

Hypovitaminosis В2 most often develops with intestinal diseases (enteritis, colitis), as well as in the absence of foods rich in riboflavin in the diet. The earliest sign of riboflavin deficiency is lip damage. At first they turn pale, reddening and cracks appear in the places of their closure. At the same time, bubbles, cracks and crusts appear in the corners of the mouth (on the lips). There is pain and a burning sensation of the tongue, which at first becomes grainy, and then smooth, purple. On the skin of the face may be peeling, especially in the nasolabial folds, eyelids, auricles. In the eyes, you may feel pain, burning, tearing, fear of light, reduced visual acuity in the dark. There are headache, apathy, tingling in the legs.

Pyridoxine (vitamin Wb) is involved in the metabolism of proteins, amino acids and fats, the formation of nicotinic acid (vitamin PP) from the amino acid tryptophan, the conversion of linoleic fatty acid into arachidonic acid in the body. Pyridoxine has a beneficial effect on blood formation and fat metabolism in atherosclerosis. The daily need of an adult person in it is 1,5 — 3 mg.

Pyridoxine is widely distributed in foods. It is found in liver (0,7 mg / 100 g), meat (0,33 — 0,39 mg / 100 g), fish (0,1 — 0,5 mg / 100 g), beans (0,9 mg / 100 g), soy (0,85 m, g / 100 g), wallpaper flour (0,55 mg / 100 g), buckwheat (0,4 mg / 100 g), millet (0,52 mg / 100 g), and also in potatoes (0,3 mg / 100 g). During heat treatment of products, about 20 — 35% pyridoxine is lost, and during storage of products in a frozen form, vitamin losses are insignificant.

Pyridoxine deficiency in humans is rare, as it can be synthesized by the intestinal bacterial flora. However, with prolonged use of sulfa drugs and antibiotics that inhibit the growth of intestinal microbes, as well as in chronic food diseasesIn the vascular system may develop hypovitaminosis Wb. It is manifested by increased irritability, drowsiness, decreased appetite, nausea, inflammation of the skin of the face (at the nasolabial fold, above the eyebrows, around the eyes), sometimes - inflammation of the lips, tongue, cracking in the corners of the mouth.

Cyanocobalamin (vitamin B12) regulates blood formation, has a beneficial effect on the central nervous system, has a pronounced lipotropic effect (prevents fatty rebirth). The daily requirement of an adult healthy person in cyanocobalamin is 3 mcg.

The main source of cyanocobalamin are products of animal origin. Most of it is found in beef liver (50 — 130 μg / 100 g), kidney (20 — 30 μg / 100 g), heart (25 μg / 100 g). Smaller it is in meat (2 — 8 μg / 100 g), cheeses (1,4 — 3,6 μg / 100 g), cottage cheese (1,0 μg / 100 g), sour cream (0,36 μg / 100 g), cream (0,45 μg / 100 μg / 0,4 g), cream (100 μg / XNUMX μg / XNUMX g), cream (XNUMX μg / XNUMX μg / XNUMX g), cream (XNUMX μg / XNUMX g), cream (XNUMX μg / XNUMX g) ), kefir (XNUMX μg / XNUMX g). Herbal products practically do not contain it.

By entering the human body with food, cyanocobalamin is connected in the stomach with the protein substance gastromucoprotein. As part of such a complex, the vitamin is not destroyed by the intestinal microflora and is absorbed. In the liver it is deposited, from where it is used by the bone marrow for blood formation on demand.

Cyanocobalamin deficiency can develop in people who do not consume animal products (vegetarians) for a long time. Its secondary insufficiency occurs in cases when the gastromucoprotein is not produced enough in the stomach and the cyanocobalamin ingested with food is not absorbed, but is destroyed by the intestinal microflora. When hypovitaminosis B12 develops malignant anemia, manifested by dizziness, general weakness, noises in the head, palpitations, shortness of breath during exercise, etc. This disease is currently successfully treated by intramuscular injection of cyanocobalamin.

Folic acid (folacin) participates (together with cyanocobalamin) in blood formation, stimulates protein synthesis, growth and development processes. It also has a lipotropic effect. An adult’s need for this vitamin is 200 µg per day.

Folic acid is widely distributed in food products, but it is contained in small quantities, and during heat treatment of 80 products — 90% it is destroyed. Beef liver contains 240 μg / 100 g of vitamin, beef — 10 μg / 100 g, fish — 4,5 — 19 μg / 100 g, curd — 35 μg / 100 g, soy — 200 μg / 100 g; 90 g, white cabbage - 100 µg / 10 g, cauliflower - 100 µg / 23 g, green onions - 100 µg / 18 g. Yeast is particularly rich in folic acid. Folic acid is synthesized by certain types of gut bacteria.

Folic acid enters the human body in a bound form. Its deficiency can develop with the inability of the body to break down the bound form of this vitamin and due to a violation of its absorption in the intestines. When folic acid deficiency affects the hematopoietic system, there are inflammatory processes in the oral cavity.

Niacin (vitamin PP) includes nicotinic acid and nicotinamide. Niacin is involved in cellular respiration, activates carbohydrate metabolism, normalizes blood cholesterol levels, water-salt metabolism. It dilates the peripheral vessels, accelerates blood flow, normalizes the reduced secretory function of the stomach. The daily requirement for niacin for an adult healthy person is 14 — 28 mg.

The source of niacin in the human body are both animal and plant products. They are rich in meat (2,4 — 3 mg / 100 g), beef liver (6,8 mg / 100 g), kidney and heart (4 mg / 100 g), soy (2,2 mg / 100 g), peas (2,2 mg / 100 g ) beans (2,1 mg / 100 g). They are the richest in yeast (30 mg / 100 g). Fish is much poorer in vitamin PP (1 — 2,8 mg / 100 g). In fruits and vegetables, nicotinic acid is contained in a small amount (0,1 — 1,5 mg / 100 g). Preservation, freezing and drying of products have little effect on the content of niacin in them. Heat treatment reduces it by 15 — 20%.

PP hypovitaminosis can develop with long-term use in the diet of corn, with treatment with anti-tuberculosis drugs that are antagonists of pyridoxine involved in the synthesis of niacin. However, most often niacin deficiency in the body is the result of defeat of the intestines with impaired absorption processes. In case of hypovitaminosis of PP, the skin on the open parts of the body and in the places of friction of its folds first turns red, then becomes dark, wrinkled, and rough. The tongue becomes bright red, transverse and longitudinal cracks, ulcerations appear on it. With hypovitaminosis PP, the secretory function of the stomach is inhibited, diarrhea occurs.

Biotin (vitamin H) is involved in the metabolism of carbohydrates, amino acids, polyunsaturated fatty acids. The need of an adult healthy person for biotin is 0,15 — 0,3 mg per day.

The source of biotin in human nutrition is liver, meat, egg yolks, and cereals. Biotin deficiency develops by consuming a large amount of raw egg whites, which contain the avidin substance that binds this vitamin. Hypovitaminosis H is manifested by flaking of the skin, muscle pain, lethargy, depression, nausea, and development of anemia.

Ascorbic acid (vitamin C) normalizes the metabolism of proteins, fats, carbohydrates, stimulates the synthesis of collagen - the main intercellular substance gluing capillary walls. Thanks to this he supports normal permeability of the capillary walls and prevents bleeding, helps to preserve the integrity of the supporting tissues (cartilage and bones). Ascorbic acid increases the body's resistance to adverse external influences and infections, improves the antitoxic function of the liver. It stimulates the formation of adrenal hormones, hemoglobin synthesis by improving the use of proteins, iron and folic acid in this process. Ascorbic acid regulates the exchange of cholesterol and many amino acids. The daily need of an adult healthy person for it is 55 — 108 mg.

The source of ascorbic acid are vegetables, fruits and berries. Dried rosehips (up to 1500 mg / 100 g), black currant (200 mg / 100 g) are especially rich in ascorbic acid. Quite a lot of this vitamin in oranges (60 mg / 100 g). However, the main source of ascorbic acid in the diet of most people in our country are green onions (30 mg / 100 g), tomatoes (26 mg / 100 g), potatoes and cabbage (20 — 40 mg / 100 g). Sauerkraut contains up to 20 mg / 100 g of ascorbic acid. Beets, carrots, cucumbers, grapes, plums, pears, peaches, bananas contain a small amount of this vitamin.

Ascorbic acid must be ingested with food daily, as it is not synthesized in it, but consumed continuously for life processes. It should be noted that ascorbic acid is unstable to the effects of high temperature and light, it collapses with long-term storage of fruits and vegetables, while cooking them in open containers. The lack of food in the diet of fresh vegetables and fruits, or their consumption after prolonged improper storage, irrational cooking, is the cause of the hypovitaminosis C, which is common in the winter-spring period.

C-vitamin deficiency is characterized by malaise, weakness, decreased performance, pain in the calf muscles, dry skin and bleeding gums, pinpoint hemorrhages in the legs.

Prevention of hypovitaminosis C is the constant consumption of fresh or canned fruits and vegetables, decoction or rosehip infusion. In our country, mandatory artificial C-fortification of food with ascorbic acid is performed in medical and childcare facilities.

Bioflavonoids (vitamin P) are contained in the same foods as ascorbic acid, in combination with which it strengthens the walls of blood vessels. Bioflavonoids contribute to the accumulation of ascorbic acid in the human body, increases its biological activity. The daily need for an adult healthy person is 25 mg.

A lack of vitamin P leads to an increase in the permeability of the capillary walls and the appearance of pinpoint hemorrhages on the skin, especially in the hair sacs. For prophylaxis P-hypovitaminosis recommended the same measures as for the prevention of the C-hypovitaminosis.

Being biologically active substances, vitamins should be ingested in sufficient quantities in the composition of food products. Often, for various diseases, preparations of individual vitamins and their combinations in the form of multivitamins are prescribed. It is not recommended to take these drugs without the advice of a doctor, as this can cause various undesirable health effects.

Fat-soluble vitamins

The group of fat-soluble vitamins include retinol (vitamin A), calciferol (vitamin D), tocopherols (vitamin E), phylloquinone (vitamin K). They are a source of food containing animal and vegetable fats.

Retinol (vitamin A) partially enters the body as a finished product. It is found in animal products: beef liver (3,83 mg / 100 g), butter (up to 0,6 mg / 100 g), cream margarine (0,4 mg / 100), margarine sandwich "Extra" (1,8 mg / 100 g), chicken eggs (0,35 mg / 100 g), sour cream (0,23 mg / 100 g). Many vegetable products contain carotene: carrots, tomatoes, sweet peppers, green onions, spinach, parsley, rose hips and sea buckthorn, apricots, lettuce, pumpkin, from which retinol is synthesized.

An adult’s need for retinol is 1000 µg per day (1 / 3 of the vitamin itself and 2 / 3 of carotene). The lack of retinol in the diet causes dry skin, furunculosis, conjunctivitis, reduced visual acuity in the dark, reduced body resistance to various infectious diseases. When hypovitaminosis A appears a tendency to inflammatory diseases of the respiratory organs, digestive system, urinary tract.

In several developing countries in Africa, Asia and Latin America, inadequate intake of retinol is the most common cause of blindness. In our country, hypovitaminosis A is rare and only in patients with severe

defeat of the intestines, liver and biliary ducts, which is accompanied by a violation of the absorption of this vitamin. In connection with the widespread use of vitamin A for medicinal purposes, there are cases of excessive consumption of it, which adversely affects health. Hypervitaminosis A, is characterized by skin itching, scaling, insomnia, headache. This condition can occur with long-term consumption of products that are very rich in retinol and carotene (liver of sea animals and fish, carrot juice).

Conventional heat treatment has almost no effect on the content of retinol in products. The absorption of carotene and transformationschenie it into retinol improves if vegetable dishes to cook with fats (eg, carrot stew with sour cream).

Calciferols (vitamin E) are represented in the human body mainly in the form of two substances: ergocalciferol (vitamin B2) and cholecalciferol (vitamin 03). Both of these substances in the human body are transformed into active forms of the vitamin.

The need for calciferol is on average 100 IU per day. A relatively large amount of calciferol is found in chicken eggs, fish eggs. They are especially high in the liver of marine fish and animals and the fat derived from them. Fish oil and marine animal fat do not belong to food and can only be used as a source of calciferol in case of their insufficiency.

The biological role of calciferols is associated with their active participation in calcium metabolism. They stimulate the absorption of calcium with its deposition in the bones. When vitamin O deficiency in children develops rickets, in adults (particularly in pregnant women), staying in the absence of sunlight, the bone tissue loses calcium and bones soften (osteoporosis).

With an overdose of vitamin B during the treatment of rickets in children, hypervitaminosis can develop, manifested by the deposition of calcium in various organs (kidneys, blood vessels, heart muscle).

Tocopherols (vitamin E) affect the metabolism of lipids, proteins and carbohydrates, stimulate muscle activity, and promote the formation of hormones that are important for the body’s vital functions. They inhibit the oxidation of polyunsaturated fatty acids, as a result of which they prevent damage to the cell membranes and the destruction of red blood cells.

The need for adult tocopherols is for men - 15 IU, for women - 12 IU per day. Their main sources are vegetable oils, and their content is much higher in unrefined oils than in refined ones. It should be borne in mind that an increase in the intake of polyunsaturated fatty acids requires the introduction of more tocopherols, which is ensured by the inclusion of unrefined vegetable oils in the diet. Tocopherols are found in eggs, wholemeal bread, cereals, legumes, milk, fish, vegetables, and fruits.

Tocopherols are used in many diseases as a therapeutic drug.

Phylloquinones (vitamin K) accelerate blood clotting and reduce capillary permeability, stimulate the repair of damaged tissues.

The need for an adult in phylloquinones is 0,2 — 0,3 mg per day. They are found in large quantities in foods such as white cabbage and cauliflower, tomatoes, pumpkin, spinach, liver, meat, eggs. Mikroflora-intestines (E. coli) has the ability to synthesize phylloquinones. Hypovitaminosis K develops only in diseases of the liver, small intestine, due to the intake of sulfonyl amide preparations (etazol, norsulfazole, etc.), as well as some antibiotics that suppress the function of the intestinal microflora.

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