Minerals in the human body are divided into macro- and microelements. The former include calcium, phosphorus, magnesium, sodium, chlorine and sulfur. The main microelements needed by the body are manganese, zinc, cobalt, iodine, fluorine, chromium, and selenium. The role of minerals in the body is difficult to overestimate - they perform many important functions, including participating in the metabolic process.
Benefits and deficiencies of minerals in the body
Minerals in the body are individual low-molecular biologically significant elements, salts and salt ions that support normal functioning body. A lack of minerals in the body can lead to various diseases, A complete absence leads to death.
The benefits of minerals are undeniable - they are involved in all biochemical processes, occurring in the body, determine the state of the blood coagulation system and muscle contractions, and are a necessary component of all organs and tissues. These elements enter the body only with food and therefore are essential components of nutrition. The metabolism of minerals in the body is precisely balanced by the amount of salts excreted from the body mainly through urine and sweat. Compound mineral salts in the cells of the body is maintained with exceptional constancy, and even small deviations can be the cause feeling unwell. The content of macro- and microelements in the human body must be balanced.
Macroelement sodium in the human body
Daily requirement macroelements (sodium, potassium, magnesium, phosphorus) more than 100 mg.
The main function of the mineral sodium is transmission nervous excitement, in muscle contraction, in regulating fluid balance in the body. It is found in regular table salt and is the reason for much controversy. This macroelement in the body is necessary for normal life, and nature has developed mechanisms that preserve sodium in conditions of its deficiency. Bad habit Adding salt to food has been developed for many years, and food without salt seems tasteless. So is it worth giving up salt? The body has enough sodium contained in natural food.
The official safe level of salt intake is 1 teaspoon per day. In fact, most people eat 2-3 times more sodium. From the salt shaker we use no more than 0.5 teaspoon of salt, the remaining 3/4 of sodium comes from finished products: bread, cheese, pickles, smoked meats, sausages, canned food, sauces, etc.
Nature has not developed mechanisms that completely protect the body from excess salt. When we eat salty foods, the ionic balance is disrupted, and water is needed to reduce the sodium concentration. With a lack of potassium, sodium is retained, retaining the water you drink. U healthy person with normally functioning kidneys and by consuming plenty of fluids and salty foods, the body can successfully cope with excess sodium and. These substances are simply excreted through sweat, tears, urine, and feces without any consequences for the body.
- Vegetables 0.002-0.06
- Fruits 0.010-0.04
- Meat 0.06-0.95
- Fish 0.08-0.12
- Cottage cheese 0.04
- Milk 0.05
- Wheat bread 0.48
- Rye bread 0.6
- Cheese 1
- Boiled sausages 2-2.5
- P/c sausages 3
- Mixed sausage 3.5
In small quantities, the macroelement sodium will not cause harm to the human body, but its excess leads to a “bouquet” chronic disorders. If a person suffers hypertension, then the kidneys are involved very early in pathological process and the ability to excrete sodium is impaired. Sodium and water accumulate in the wall blood vessels and tissues, while vascular tone increases and their tendency to spasm increases, which leads to increased blood pressure and increased load on the heart.
Some people have hereditary predisposition to impaired sodium excretion by the kidneys, which can also cause the development of hypertension. Such patients are called salt-sensitive. They themselves often observe fluid retention in their body: swelling of the face, limbs, increased blood pressure, and sometimes the development hypertensive crisis(often when eating salty foods).
The importance of the macronutrient potassium for the body
The potassium content depends on the concentration of sodium in the blood, and the body monitors the potassium-sodium balance especially sensitively. If sodium predominates in the extracellular fluid, then potassium is present mainly inside the cells. The main manifestations of potassium deficiency in the body are muscle weakness, sometimes very strong, fast fatiguability, cardiopalmus. Lack of potassium leads to disruption of cardiac function and conduction of nerve pathways.
The daily requirement for potassium is 2.5-4 g.
Potassium content (g) per 100 g of products:
- Dried apricots 2.0
- Wheat bran 1.1
- Beans 1.1
- Soy 1.6
- Raisins 0.87
- Spinach 0.77
- Walnuts 0.69
- Potatoes 0.57
- Chocolate 0.54
The cause of such ailments can be not only potassium deficiency, but also excess sodium. The importance of the macroelement potassium for the body is its protective effect against the undesirable effects of excess sodium and the normalization of blood pressure. Potassium helps remove excess fluid from the body and improve the activity of the heart muscle. Excess potassium is excreted in the urine, which also removes unnecessary sodium. If there is little sodium in the body, it is reabsorbed in the kidneys and only potassium is excreted.
Potassium-rich foods can be eaten without fear; they will only be beneficial.
The role of the macronutrient calcium for the body
The main role of the macroelement calcium in the human body is to normalize the functioning of the heart, regulate the excitability of the nervous and muscle cells, participation in blood clotting processes. Calcium is part of bones and teeth, but it is one of the most difficult to digest elements. It is poorly absorbed without unsaturated fats; when boiled, it turns into indigestible forms and forms insoluble compounds with phosphates and oxalic acid.
The daily calcium requirement for an adult is 0.8-1 g, for children - 1-1.2 g, for pregnant and nursing mothers - up to 2 g.
Calcium content (g) per 100 g of products:
- Powdered milk 0.9
- Tahini halva 0.8
- Cheese 0.7- 1.0
- Sunflower seeds 0.4
- Soy 0.3
- Wheat bran 0.2
- Dates 0.2
- Cottage cheese 0.15-0.18
When the body's cells don't get enough calcium from food, they begin to take it away from the bones. With age, bones become fragile, especially for postmenopausal women.
The best absorption of calcium depends on its ratio with other salts, especially phosphates and magnesium. if you accept vitamin complexes with calcium, make sure you get enough vitamin D; without it, the body cannot absorb calcium.
Potassium, calcium and magnesium play important role in myocardial nutrition, maintenance vascular tone and regulation of biochemical processes in the body.
Macroelement phosphorus and its significance
The importance of phosphorus salts is not limited to their participation in bone formation. They are energy accumulators, which are used during muscle contraction, in biochemical processes occurring in the brain, liver and other organs.
The daily requirement for phosphorus is 1 - 1.5 g. The rate of phosphorus consumption for people engaged in heavy physical labor and athletes can increase to 1.5-2 g.
For proper nutrition Not only the absolute amount of phosphorus is important, but also its ratio with calcium (2:3). With an excess of phosphorus, calcium can be removed from the bones, and with an excess of calcium, urolithiasis can develop.
The required amount of phosphorus is easily obtained from almost any food, and phosphorus deficiency is rare. The distribution of phosphorus is regulated by vitamin D.
Function of the macronutrient magnesium in the human body
Magnesium has a vasodilator and diuretic effect. The exchange of phosphorus and magnesium salts is closely related. A lack of magnesium salts in food disrupts the normal excitability and conductivity of the nervous system and muscle contraction.
The average daily requirement of an adult for magnesium is 400 mg/day. With normal nutrition, the body's need for magnesium is usually fully met.
Magnesium content (g) per 100 g of products:
- Wheat bran 0.6
- Pumpkin seed 0.5
- Soy 0.2
- Watermelon 0.23
- Peanuts 0.18
- Oatmeal 0.16
- Buckwheat 0.11
- Dried apricots 0.1
The “magnesium diet” is prescribed for diseases of the liver, gallbladder, arterial hypertension, coronary disease hearts.
With a lack of magnesium, appetite decreases, more severe cases convulsions may even occur.
Iron is a trace element necessary for the human body.
The daily requirement of microelements in the human body (iron, copper, iodine, fluorine, selenium) is less than 100 mg.
Iron compounds are essential integral part most tissues of the body. They are necessary for the formation of new red blood cells (red blood cells that carry oxygen). An imbalance of this microelement is detrimental to the body; it leads to the development iron deficiency anemia and other diseases.
The daily requirement for the microelement iron in the body is 12 mg.
- Sunflower seeds 0.061
- Tahini halva 0.050
- Dried apricots 0.024
- Apples 0.015
- Prunes 0.013
- Pork liver 0.012
Iron is absorbed from fruits and vegetables by 80%, and from animal products and bread by 25-40%.
The role and deficiency of the microelement copper in the body
Deficiency of the microelement copper in the body negatively affects hematopoiesis, iron absorption, and disrupts menstrual function, increases the predisposition to bronchial asthma, allergic dermatoses. Increased content copper is observed in acute and chronic inflammatory diseases, kidney and liver diseases. The main role of the microelement copper in the human body is participation in the synthesis of erythrocytes and leukocytes.
The effect of the microelement iodine on the body
The beneficial effect of the microelement iodine on the body affects the metabolism of patients with atherosclerosis. Lack of iodine leads to disease thyroid gland. A large number of iodine is found in seafood products. The foods richest in iodine are: seaweed, fish, shellfish, crabs.
Content of the microelement fluorine in the body
Fluoride salts are part of dental tissue, especially tooth enamel. A lack of fluoride leads to an increase in the incidence of caries. Typically, 1 liter of drinking water contains from 1 to 1.5 mg of fluoride. The maximum permissible concentration of fluorine salts is 1.5 mg/l. The fluorine content in the human body is about 2.6 g.
Lack of the trace element selenium in the body
If there is a lack of the microelement selenium in the body, the following changes may occur: decreased immunity, increased tendency to inflammatory processes, decreased liver function, skin and hair diseases, reproductive failure.
Selenium deficiency accelerates the development of atherosclerosis.
Selenium is able to protect the body from harmful effects heavy metals: mercury, arsenic and cadmium, to a lesser extent - from lead and thallium.
How to neutralize free radicals in the body
Free radicals in the body are by-products and are unstable molecules that require an electron to stabilize. This conditions them excessive activity: the free radical looks for this electron everywhere, causing chemical reactions, and many of them can harm our body, causing the oxidation of some important substances. Oxidation in chemistry is a reaction in which a substance loses electrons. And in our case, these electrons go to the free radical. It provokes this reaction by taking electrons from important molecules - proteins, fats and DNA, damaging them. Normally, these processes are very minor, since the production of free radicals is usually low. Under the influence of chemical factors (for example, components tobacco smoke), with a lack of vegetables and fruits in the menu, stress, physical inactivity, the number of free radicals increases sharply.
What can neutralize excess free radicals, which are formed in our body? Special compounds - antioxidants are like “scavengers” that neutralize free radicals. The most well-known antioxidants are vitamin A and carotenes. They are called ACE vitamins. Antioxidants are involved in a large number of biochemical reactions, many of which protect our blood vessels and heart.
One more important substance, or rather, a metal with antioxidant activity is selenium. It is involved in oxidative processes, prevents hardening of arteries, and plays an important role in male reproduction and maintaining normal function thyroid gland.
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Minerals (in nutrition) are essential components of food necessary for the life of humans and animals. The complete exclusion of minerals from feed in an experiment leads to the death of animals, and partial restriction causes a number of serious violations and disorders.
Minerals are found in the protoplasm of cells and intercellular fluid, creating the necessary osmotic pressure (see) and the required concentration hydrogen ions; are an integral part of complex organic compounds, vital for the body (for example, iron is part of hemoglobin, iodine is found in the secretion of the pancreas and gonads). Minerals play an important role in metabolism (see. Mineral metabolism). They participate in the synthesis of digestive processes and ensure the normal course of processes. Minerals are involved in plastic processes, especially in the construction of bone substance, where they are the main structural components. In the formation of the substance of teeth, it plays an important role, which gives them special strength. The role of minerals in maintaining acid-base balance in organism. The predominance of acidic or alkaline mineral substances in the diet can affect changes in the acid-base balance. Sources of acidic minerals are those containing significant amounts of phosphorus,. Such products are meat, eggs, cereals. Sources of alkaline minerals are milk, vegetables, fruits rich in calcium, magnesium, sodium, potassium. Depending on the quantities in which minerals are contained in the body, they are divided into macroelements and microelements. Macroelements are calcium, phosphorus, magnesium, sodium, chlorine, iron, etc. Microelements contained in tissues in amounts less than 0.01% include copper, zinc, cobalt, manganese, iodine, fluorine, etc.
The body's need for minerals is satisfied by food and partly by water.
Calcium makes up mineral base bone tissue and teeth. The calcium content in bones reaches 99% of the total amount in the body. The absorption of calcium depends on the content of other salts in food, especially magnesium, as well as vitamins of group D. In the diet, the most favorable ratio of calcium to phosphorus is 1: 1.5-2 and calcium to magnesium is 1: 0.75. Consumption of large amounts of fat in food reduces the absorption of calcium. Inositol phosphoric acid, contained in significant quantities in bread and cereals, and contained in sorrel and spinach, form insoluble compounds with calcium, and therefore the calcium of these products is not absorbed. A good source of easily digestible calcium is milk, containing 120 mg of calcium per 100 g of product (120 mg%), and dairy products: cottage cheese - 140 mg%, cheese - 700-1000 mg%. 3 glasses of milk or 100 g of cheese satisfy the daily calcium requirement of an adult. Vegetables and potatoes are good sources of calcium. In particular, cabbage contains 48 mg% calcium, potatoes - 10 mg% calcium. The daily requirement for calcium is 800-1000 mg. An increased need for calcium (up to 1.5-2 g per day) exists in children and adolescents, pregnant and lactating women.
Minerals in food - series chemical elements, entering the body with food in the form of mineral salts. Minerals are mandatory part diet are among the main nutrients and have biological activity. A number of minerals (iron, copper, cobalt, nickel, manganese) play an important role in hematopoiesis, in the processes of tissue respiration and intracellular metabolism. The plastic properties of mineral substances and their participation in the formation and regeneration of body tissues, especially skeletal bones, where phosphorus and calcium are the main structural components, have been studied. One of the most important functions of minerals is maintaining acid-base balance (see).
Satisfaction of the body's need for minerals is carried out mainly from consumed food products(table).
Potassium(see) is capable of increasing the excretion of fluid and sodium salts from the body. Sources of potassium include cereals, vegetables, potatoes, fruits, meat and fish products. There is especially a lot of potassium in dried fruits (apricots, raisins, prunes, etc.). The body's daily need for potassium is 2-3 g.
Calcium(see) is a constant component of blood, cellular and tissue juices of bones. Calcium is found in significant quantities in many foods, but it is difficult to digest. The absorption of calcium depends on its ratio with accompanying food components - magnesium, phosphorus, etc. The ratios favorable for the absorption of calcium are: with phosphorus 1: 1.5 and with magnesium 1: 0.75. Optimal conditions in all respects for complete absorption of calcium are found in milk and dairy products. Calcium cereal products They are poorly absorbed due to the presence of inositol phosphoric acid, which forms indigestible compounds with calcium. Vitamin D plays a regulatory role in the absorption of calcium (see). The body's daily need for calcium is 800-1000 mg.
Magnesium(see) has an antispastic and vasodilating effect, and is also capable of stimulating intestinal motility and increasing the secretion of bile. There is evidence of a decrease in blood cholesterol levels with a magnesium diet. The main sources of magnesium in human nutrition are cereals (rye, wheat) and legumes (peas, beans). The body's daily need for magnesium is 500-600 mg.
Phosphorus(see) participates in all types of metabolism. Many of its compounds are with protein, fatty acids etc. form complex compounds of high biological activity- casein, lecithin, etc. The absorption of phosphorus depends on its ratio, primarily with calcium. The main sources of phosphorus are dairy products (especially cheese), eggs, caviar, liver, meat, fish, etc. The daily requirement for phosphorus is 1600 mg.
Iron(see) is a true hematopoietic element. Liver, beans, peas are high in iron, oat groats. The body's daily requirement for iron is 15 mg.
The high content and predominance of calcium, magnesium, sodium or potassium in food products determines their alkaline orientation, and such products can be considered as sources of alkaline elements ( herbal products- legumes, vegetables, fruits, berries, and animal products - milk and dairy products). Acidic minerals enter the body with foods containing sulfur, phosphorus and chlorine (meat and fish products, eggs, bread, cereals).
A special group of mineral substances are microelements (see), which are contained in food products in small quantities (units or fractions of mg%). Microelements according to their own biological properties are true bioelements. See also Mineral metabolism.
Table. Content of essential minerals in some food products (in mg%, gross)
| Product name | K | Ca | Mg | P | Fe |
| Rye bread | 249,0 | 29,0 | 73,0 | 200,0 | 2,0 |
| Wheat bread and loaves made from grade II flour | 138,0 | 28,0 | 47,0 | 164,0 | 2,0 |
| Buckwheat | - | 55,0 | 113,0 | 291,0 | 1,8 |
| Oatmeal | 350,0 | 74,0 | 133,0 | 322,0 | 4,2 |
| Semolina | 166,0 | 41,0 | 68,0 | 101,0 | 1,6 |
| Millet groats | 286,0 | 30,0 | 87,0 | 186,0 | 0,7 |
| Rice | 63,0 | 29,0 | 37,0 | 102,0 | 1,3 |
| Pasta | 138,0 | 34,0 | 33,0 | 97,0 | 1,5 |
| White cabbage | 148,0 | 38,0 | 12,0 | 25,0 | 0,9 |
| Potato | 426,0 | 8,0 | 17,0 | 38,0 | 0,9 |
| Bulb onions | 153,0 | 32,0 | 12,0 | 49,0 | 0,7 |
| Carrot | 129,0 | 34,0 | 17,0 | 31,0 | 0,6 |
| cucumbers | 141,0 | 22,0 | 13,0 | 26,0 | 0,9 |
| Radish | 180,0 | 28,0 | 9,0 | 20,0 | 0,7 |
| Beet | 155,0 | 22,0 | 22,0 | 34,0 | 1,1 |
| Tomatoes | 150,0 | 10,0 | 9,0 | 22,0 | 1,2 |
| Oranges | 148,0 | 25,0 | 10,0 | 17,0 | 0,3 |
| Grape | 225,0 | 15,0 | 6,0 | 20,0 | 0,5 |
| Black currant | 365,0 | 35,0 | 17,0 | 42,0 | 0,9 |
| Apples | 86,0 | 16,0 | 9,0 | 11,0 | 2,2 |
| Milk | 127,0 | 120,0 | 14,0 | 95,0 | 0,1 |
| Cottage cheese (low fat) | - | 164,0 | - | 151,0 | - |
| Cheese (Dutch) | - | 699,0 | - | 390,0 | - |
| Lamb I category (chilled) | 214,0 | 7,0 | 15,0 | 136,0 | 1,9 |
| Beef category I (chilled) | 241,0 | 8,0 | 16,0 | 153,0 | 2,1 |
| Pork meat (chilled) | 240,0 | 8,0 | 16,0 | 153,0 | 2,1 |
| Beef liver | 307,0 | 5,0 | 17,0 | 316,0 | 8,4 |
| Sausages (amateur, separate) | 213,0 | 7,0 | 15,0 | 137,0 | 1,9 |
| Chicken eggs | 116,0 | 43,0 | 10,0 | 184,0 | 2,1 |
| Far Eastern flounder | 151,0 | 49,0 | 14,0 | 154,0 | 0,2 |
| Sea bass (gutted, without head) | 245,0 | 38,0 | 18,0 | 162,0 | 0,5 |
| Cod | 281,0 | 44,0 | 19,0 | 173,0 | 0,5 |
| Atlantic herring | 209,0 | 84,0 | 28,0 | 127,0 | 2,2 |
| Peas | 906,0 | 63,0 | 107,0 | 369,0 | 4,7 |
| Beans | 1061,0 | 157,0 | 167,0 | 504,0 | 6,7 |
MINERALS, THEIR ROLE AND IMPORTANCE IN HUMAN NUTRITION.
BIOMICRLEMENTS, ENDEMIC DISEASES
Minerals are essential nutrients that enter the body with food. The importance of minerals in human nutrition is very diverse: they are included in the complex of substances that make up the living protoplasm of cells, in which the main substance is protein, in the composition of all intercellular and interstitial fluids, providing them with the necessary osmotic properties, in the composition of supporting tissues, skeletal bones and in the composition of tissues such as teeth, in which hardness and special strength are required. In addition, minerals are present in some endocrine glands (iodine - in the thyroid gland, zinc - in the pancreas and gonads), are present in some complex organic compounds (iron - in Hb, phosphorus - in phosphatides and etc.), and also in the form of ions participate in the transmission of nerve impulses and ensure blood clotting.
The importance of minerals for a growing organism is great. The increased need for them in children is explained by the fact that the processes of growth and development are accompanied by an increase in cell mass and mineralization of the skeleton, and this requires the systematic intake of a certain amount of mineral salts into the child’s body.
Minerals enter the body mainly through food. Elements, i.e. Minerals found in foods can be divided into three groups: macroelements, microelements and ultramicroelements.
Macronutrients are present in products in significant quantities - tens and hundreds of mg%. These include: phosphorus (P), calcium (Ca), potassium (K), sodium (Na), magnesium (Mg).
Microelements present in food products in quantities of no more than a few mg%: fluorine (F), cobalt (Co), iron (Fe), manganese (Mn), copper (Cu), zinc (Zn), etc.
Ultramicroelements- their content in products, usually in μg%: selenium (Se), gold (Au), lead (Pb), mercury (Hg), radium (Ra), etc.
Macronutrients
One of the most important minerals is calcium(Sa). Calcium is a constant component of blood, it is involved in blood clotting, is part of cellular and tissue fluids, and is part of cell nucleus and plays an important role in the processes of cell growth and activity, as well as in the regulation of the permeability of cell membranes, participates in the processes of transmission of nerve impulses, muscle contraction, and controls the activity of a number of enzymes. The main importance of calcium is its participation in the formation of skeletal bones, where it is the main structural element (calcium content in bones reaches 99% of the total amount in the body).
The need for calcium is especially increased in children, in whose bodies bone formation processes occur. The need for calcium also increases during pregnancy and, especially, in nursing mothers.
A long-term lack of calcium in food leads to impaired bone formation: rickets in children, osteoporosis and osteomalacia in adults.
Calcium metabolism is characterized by a feature that lies in the fact that if there is a lack of it in food, it continues to be excreted from the body in significant quantities due to the body’s reserves (bones), which causes calcium deficiency (in China, in the Shangi province, where there was a vicious custom of feeding mothers in within a month after the birth of the child only rice porridge, a huge number of women turned into cripples due to osteomalacia).
Calcium is one of the hard-to-digest elements. Moreover, its digestibility depends on the relationship with other food components and, first of all, with phosphorus, magnesium, as well as protein and fat.
The absorption of calcium is primarily influenced by its ratio with phosphorus. The most favorable ratio of calcium and phosphorus is 1:1.5, when easily soluble and well-absorbed calcium phosphate salts are formed. If there is a significant excess of phosphorus in food compared to calcium, then tribasic calcium phosphate is formed, which is poorly absorbed (Table 1).
|
Products |
Ca:P ratio |
||
|
Rye bread | |||
|
Wheat bread | |||
|
Buckwheat | |||
|
Oatmeal | |||
|
Potato | |||
|
Fresh milk | |||
|
Condensed milk | |||
|
Beef | |||
|
Chicken eggs | |||
|
Canned fish | |||
|
Canned cod in oil | |||
|
Canned sprat in oil |
Excess fat in food has a negative effect on calcium absorption, since this produces a large amount of calcium soaps, i.e. calcium compounds with fatty acids. In such cases, the usual amount of bile acids is not enough to convert calcium soaps into complex soluble compounds, and these calcium soaps are excreted in indigestible form in the feces. Favorable ratio of calcium to fat: per 1 g of fat there should be at least 10 mg of calcium.
Excess magnesium in the diet has a negative effect on calcium absorption. This is explained by the fact that for the breakdown of magnesium soaps, as well as calcium soaps, it is required bile acids. The optimal ratio of Ca: Mg is 1:0.5.
Oxalic and inositol phosphoric acids, which form insoluble salts, have an adverse effect on the absorption of calcium. Oxalic acid is found in significant quantities in sorrel, spinach, rhubarb, and cocoa. A lot of inositol phosphoric acid is found in cereals.
A sufficient content of complete proteins and lactose in food has a beneficial effect on the absorption of calcium.
One of the decisive factors for good calcium absorption, especially in young children, is vitamin D.
Calcium is best absorbed from milk and dairy products. However, even if up to 80% of the body's need for calcium is satisfied through these products, its absorption in the intestine usually does not exceed 50%. At the same time, in a mixed diet, it is dairy products that make it possible to provide a sufficient amount of calcium and its optimal ratio, ensuring good absorption of this macronutrient.
Green onions, parsley, and beans also contain calcium. Significantly less in eggs, meat, fish, vegetables, fruits, berries.
The source of calcium can be bone flour, which has good digestibility (up to 90%) and can be added in small quantities to various dishes and culinary products (porridge, flour products).
A particularly high need for calcium is observed in patients with bone injuries and in tuberculosis patients. In patients with tuberculosis, along with the breakdown of protein, the body loses a large amount of calcium and therefore a tuberculosis patient needs a large supply of calcium into the body.
Phosphorus(P) is involved in the metabolism of carbohydrates, fats and proteins. It is an element included in the structure of the most important organic compounds, is part of nucleic acids and a number of enzymes, and is also necessary for the formation of ATP. In the human body, up to 80% of all phosphorus is found in bone tissue, and about 10% is found in muscle tissue.
The body's daily requirement for phosphorus is 1200 mg. The body's need for phosphorus increases with insufficient protein intake from food and especially with increased physical activity. In athletes, the need for phosphorus increases by 2.5 mg, and sometimes by 3 - 4.5 mg per day.
Above are data on the phosphorus content in some food products and its ratio with calcium (see Table 1). In food products of plant origin, phosphorus is found in the form of salts and various derivatives of orthophosphoric acid and, mainly, in the form of organic compounds of phosphoric acid - in the form of phytin, which is not broken down in the human intestine (there is no enzyme). Its minor breakdown occurs in the lower sections due to bacteria. Phosphorus is found in the form of phytin in cereal products (up to 50%). The breakdown of phytin is facilitated by the production of bread with yeast and an increase in the rising time of the dough. In cereals, the amount of phytin is reduced when they are pre-soaked overnight in hot water.
If necessary, the phosphorus content in diets can be increased through various products. Here is the data on the phosphorus content in some food products, mg%:
Meat and fish products 140 - 230
Hard cheeses 60 - 400
Eggs 210-215
Bread 108-222
Groats (buckwheat, oatmeal, millet) 220-330
Legumes 370-500
Magnesium (Mg), along with potassium, is the main intracellular element. It activates enzymes that regulate carbohydrate metabolism, stimulates the formation of proteins, regulates the storage and release of energy in ATP, reduces excitation in nerve cells, relaxes the heart muscle, increases intestinal motor activity, and promotes the removal of toxins and cholesterol from the body.
The absorption of magnesium is hindered by the presence of phytin and excess fat and calcium in food.
The daily requirement for magnesium is 400 mg per day. In pregnant and lactating women, the need increases by 50 mg per day. With a lack of magnesium in the diet, food absorption is impaired, growth is delayed, and calcium is found in the walls of blood vessels.
Here is the data on the magnesium content in some food products, mg%:
Wheat bread 25- 51
Bread with bran 60-90
Unpeeled rice, beans, peas 120-150
Buckwheat 78
Sea fish and other seafood 20-75
Beef meat 12-33
Milk 9-13
Hard cheeses 30-56
Parsley, dill, salad 150-170
Apricots, apricots, raisins 50-70
Bananas 25- 35
Thus, mainly plant foods are rich in magnesium. Wheat bran, cereals (oatmeal, etc.), legumes, apricots, dried apricots, apricots, and raisins contain large quantities. There is little magnesium in dairy products, meat, and fish.
Micro- and ultramicroelements
Iron(Fe) is necessary for the biosynthesis of compounds that ensure respiration and hematopoiesis, participates in immunobiological and redox reactions, and is part of the cytoplasm, cell nuclei and a number of enzymes.
Prevents iron assimilation oxalic acid and phytin. For absorption, B12 and ascorbic acid are required.
Requirement: men 10 - 20 mg per day, women 20 - 30 mg per day.
With iron deficiency, anemia develops, gas exchange and cellular respiration are disrupted. Excess iron can have a toxic effect on the liver, spleen, brain, and increase inflammatory processes in the human body. With chronic alcohol intoxication, iron can accumulate in the body, leading to copper and zinc deficiency.
Here is the data on the iron content in some food products, mg%:
Wheat and rye bread 3 - 4
Soybeans, lentils 6-9
Beef meat 9-10
Poultry 2-8
Pork liver 15 - 20
Beef and pork kidneys 9-10
Lungs, heart 4 - 5
Spinach 3 - 4
Corn, carrots 2 - 2.5
Eggs 2 - 2.5
Sea fish 2 - 3
However, iron is found in easily digestible form only in meat products, liver, and egg yolk.
Zinc(Zn). Insufficient intake of this microelement into the body leads to decreased appetite, anemia, lack of body weight, decreased visual acuity, hair loss, and contributes to the occurrence of allergic diseases and dermatitis. T-cell immunity is specifically reduced, which leads to frequent and prolonged colds and infectious diseases. Due to zinc deficiency, boys experience delayed sexual development.
Excessive intake of zinc can reduce the overall content of such an important element as copper in the body.
The body's daily need for zinc ranges from 12 to 50 mg, depending on gender, age and other factors. Here is the data on the zinc content in some food products, mg%:
Wheat and rye bread 2 - 4.5
Animal meat 2 - 5
Internal organs of animals 15 - 23
Fish 0.7-1.2
Crabs 2 - 3
Oysters 100-400
Dry cream, hard cheeses 3.5 - 4.5
Soybeans, lentils, green pea 3 - 5
Oats and cereals 4,5 - 7,6
Corn 2 - 3
Blueberry 10
Selenium (Se). IN last years This ultramicroelement is given a lot of attention in human nutrition. This is due, first of all, to its influence on a wide variety of processes in the body. With a deficiency of selenium in the diet, immunity and liver function decrease, and there is an increased tendency to inflammatory diseases, cardiopathy, atherosclerosis, diseases of the skin, hair and nails, and the development of cataracts. Growth slows down and reproductive function is impaired. A relationship has been identified between selenium deficiency in diets and the incidence of stomach, prostate, colon and breast cancer.
Selenium is an antagonist of mercury and arsenic, due to which it is able to protect the body from these elements and cadmium when they enter the body in excess.
The daily requirement for selenium ranges from 20 to 100 mcg, which, in normal conditions, is ensured through a variety of food products. At the same time, the limited range of products that is characteristic of our days due to economic reasons can lead to a deficiency of this element in the population’s diet. Here is the data on the selenium content in some food products, mg%:
Wheat bread 60
Beef meat 10 - 350
Chicken meat 14 - 22
Beef heart 45
Liver 40 - 60
Pork lard 200 - 400
Sea fish 20 - 200
Soybeans, lentils, sunflower seeds 60 - 70
Garlic 200-400
Pistachios 450
As can be seen from the above, the selenium content in food products can vary within fairly wide limits. This is most often associated with the natural biogeochemical characteristics of individual territories. Thus, in our country, selenium-deficient provinces include the North-Western region (Republic of Karelia, Leningrad region), Upper Volga region (Yaroslavl, Kostroma and Ivanovo regions), Udmurt Republic and Transbaikalia. By the way, it was precisely with selenium deficiency in the North-Western region of our country, as well as in other countries adjacent to it (Finland, Sweden, Norway), that efforts were made at the beginning of the 20th century. explain the cause of alimentary-paroxysmal-toxic myoglobinuria (Haffian and Yuksovsky disease) - food poisoning of unknown etiology recorded in this region. However, this point of view was not confirmed, especially since in subsequent years this disease was repeatedly described in the Novosibirsk region (Sartlan disease), where there is no natural deficiency of selenium.
Copper(Cu). Refers to microelements that have natural biogeochemical provinces with a deficiency of content and artificial biogeochemical provinces with a content that significantly exceeds the norm. Swampy and soddy-podzolic soils are especially poor in copper, on which the products grown also contain little copper.
Copper deficiency negatively affects hematopoiesis, iron absorption, the condition of connective tissue, myelination processes in nervous tissue, increases predisposition to bronchial asthma, allergic dermatoses, cardiopathy, vitiligo and many other diseases, and disrupts menstrual function in women.
Increased copper content in the body is often observed in acute and chronic inflammatory diseases, bronchial asthma, liver and kidney diseases, myocardial infarction and some malignant neoplasms. The mechanism of this increase is not entirely clear and, obviously, is not a consequence of excess intake, but the result of changes in the metabolic processes of the body.
Chronic copper intoxication, when supplied in excess in technogenic regions with high concentrations, leads to functional disorders of the nervous system, kidney liver, ulceration and perforation of the nasal septum, and allergic dermatoses.
The body's daily requirement for copper is 1 - 2 mg. Here is the data on the copper content in some food products, mg%:
Cucumbers 8 - 9
Pork liver 3.6 - 7.6
Nuts 2.8-3.7
Cocoa beans 3 - 4
Chocolate 1.1 - 2.7
Rose hips 1.5 - 2
Hard cheeses 1 - 1.2
Poultry meat 0.1 - 0.5
Eggs 0.05-0.25
Mushrooms 0.2-1
Fish 0.1-0.6
Walnut 0.9
Parsley, dill, cilantro 0.85
Beef and pork liver 3 - 3.8
Various meats 0.1-0.2
Thus, the required amount of copper in regular diets can only be achieved by combining a variety of foods, including rich sources of this trace element. When using products obtained in technogenic biogeochemical provinces and containing excess amounts of copper, the opposite problem may arise - reducing the total copper content in the diet through the use of products exported from other regions with low copper content.
Cobalt (So). This ultramicroelement is known to be a component of the vitamin B 12 (cyanocobalamin) molecule, synthesized under normal conditions in the human body. This vitamin is necessary to ensure rapid cell division, primarily in the hematopoietic tissues of the bone marrow and nerve tissues. The role of cobalt in stimulating erythropoiesis is great.
With insufficient intake of cobalt from food, anemia develops. With a strict vegetarian diet, women experience menstrual irregularities, degenerative changes in the spinal cord, and skin hyperpigmentation. It must be remembered that often anemia and other manifestations of deficiency of cobalt and its organically bound form - vitamin B 12 are caused not by a deficiency of intake, but by a decrease in their absorption, due to the presence of mucoprotein synthesized in the gastric mucosa.
A deficiency in cobalt intake may be associated with living in biogeochemical provinces, as well as with exposure to certain occupational hazards (for example, carbon disulfide) that disrupt its metabolism in the human body. The daily requirement of the human body for cobalt is 14-78 mcg. Here is the data on the cobalt content in some food products, mg%:
Beef and pork liver 19 - 20
Beef and pork meat 7 - 8
Rabbit meat 15.5-16.2
Beef and pork kidneys 8 - 9
Beans and peas 8
River fish 0 - 35
Sea fish 12 - 40
Squid 95
Shrimp 120
Beetroot, lettuce, parsley 3 - 4
Black currant 4
Red pepper 3 - 3.5
Buckwheat and millet 3
Manganese(Mn). Plays an important role in cell metabolism. It is part of the active center of many enzymes and plays a certain role in protecting the body from the harmful effects of peroxide radicals.
Lack of manganese leads to impaired carbohydrate metabolism such as non-insulin-dependent diabetes, hypocholesterolemia, delayed hair and nail growth, increased convulsive readiness, allergies, dermatitis, impaired cartilage formation and osteoporosis. With the development of osteoporosis, calcium intake will aggravate manganese deficiency, as it complicates its absorption in the body. The absorption of manganese in the body is also hampered by phosphates, iron, and foods containing large amounts of tannin and oxalates (tea, spinach, etc.). An excess of manganese in the diet increases the deficiency of magnesium and copper.
The body's daily requirement for manganese is 2 - 9 mg. Here is the data on the manganese content in some food products, mg%:
Wheat and rye bread 1.2 - 2.3
Sliced loaf of bread 0.8
Millet and buckwheat groats 1.1-1.5
Beans and peas 1.3-1.4
Beetroot, dill, parsley 0.7 - 0.8
Raspberries, black currants 0.6 - 0.9
Beef kidneys and liver 0.16 - 0.3
Iodine (I). The main role of iodine in the body is to participate in the formation of thyroid hormones. In addition, it takes part in the oxidation of fats, controls and organizes the protective mechanisms of the human body. Indirectly, through thyroid hormones, iodine affects nervous system, determines normal energy metabolism, the quality of reproductive health, affects the mental and physical development of the child’s body.
Iodine enters the body mainly through the digestive tract, a small amount through the lungs with inhaled air, and very little through the skin.
Inorganic iodine entering the body enters the thyroid gland through the bloodstream and is captured by active proteins, turning into component hormone - thyroxine. During the day, 100 - 300 mcg of hormonal iodide enters the blood from the thyroid gland. Iodine consumption is replenished by its intake from food.
The problem of iodine deficiency is extremely relevant for our country, since more than 50% of its territory has a lack of iodine in water and soil, and hence in food products of local origin.
Research conducted in different countries of the world, have shown that in regions of severe iodine deficiency, cretinism occurs in 1 - 10% of the population, neurological disorders and mental retardation occur in 5 - 30%, and decreased mental abilities occur in 30 - 70%. The result of chronic iodine deficiency is the development endemic goiter.
Iodine deficiency conditions are not rare. According to WHO, more than 1.5 billion people on our planet are at risk of developing such disorders. Iodine deficiency is observed throughout almost the entire territory of our country. The most widely known in this regard are the foothill and mountainous regions of the North Caucasus, the Urals, Altai, the Siberian Plateau, and the Far East. Iodine-deficient territories include the regions of the Upper and Middle Volga region, Verny and Central regions of the European part of the country. About 100 million Russians live in their territories. Conducted studies show that even in the Tambov and Voronezh regions The frequency of goiter in schoolchildren reaches 15 - 40%. The percentage of goiter detection is also high among schoolchildren in Moscow and the Moscow region - 14 and 29%, respectively (M.V. Veldanova, A.V. Skalny, 2001).
Prevention of iodine deficiency should be carried out in several directions, of which the main one should be to ensure the supply of sufficient amounts of iodine with food through natural foods with a high iodine content.
Here is the data on the iodine content in some food products, mg%:
Sea kale Up to 3000
Cod 135
Shrimp 110
Chicken egg 20
Animal meat 6.8 - 7.2
Beef liver 6.3
Beetroot Up to 7
Poultry 4 - 5.6
Potatoes 5
Cow's milk 16
Cream 20% 9.3
Beans and soybeans 8.2-12.1
Salad, grapes 8
Various breads 3 - 5.6
Various cereals 3.3 - 5.1
Walnuts 3.1
The richest dietary sources of iodine are seafood, as well as milk and chicken eggs. As for products of plant origin, the data provided are average. In natural biogeochemical provinces deficient in iodine, its content may be significantly lower. In this case important purchases the import of products from other iodine-free territories.
But often this way does not solve the problem of providing iodine. In these In some cases, they resort to using special food products fortified with iodine in the diet of the population - iodized salt, iodized oil, bread, milk and other products fortified with iodine.
Minerals play an extremely important role in the life of living organisms. Along with organic substances, minerals are part of organs and tissues, and also participate in the metabolic process.
All mineral substances, based on their quantitative content in the human body, are usually divided into several subgroups: macroelements, microelements and ultraelements.
Macronutrients are a group of inorganic chemicals present in the body in significant quantities (from several tens of grams to several kilograms). The group of macroelements includes sodium, potassium, calcium, phosphorus, etc.
Microelements found in the body in much smaller quantities (from several grams to tenths of a gram or less). These substances include: iron, manganese, copper, zinc, cobalt, molybdenum, silicon, fluorine, iodine, etc.
Ultramicroelements, are contained in the body in extremely small quantities (gold, uranium, mercury, etc.).
The role of minerals in the body
Mineral (inorganic) substances included in the structure of the body perform many important functions. Many macro and microelements are cofactors of enzymes and vitamins. This means that without mineral molecules, vitamins and enzymes are inactive and cannot catalyze biochemical reactions (the main role of enzymes and vitamins). Activation of enzymes occurs through the addition of atoms of inorganic (mineral) substances to their molecules, while the attached atom of an inorganic substance becomes the active center of the entire enzymatic complex.
The entire set of macro and microelements ensures the processes of growth and development of the body. Minerals play an important role in regulating immune processes, maintaining the integrity of cell membranes, and ensuring tissue respiration.
Maintaining Consistency internal environment(homeostasis) of the body, primarily involves maintaining the qualitative and quantitative content of minerals in tissues and organs at a physiological level. Even small deviations from the norm can lead to the most severe consequences for the health of the body.
Sources of minerals
The main source of minerals for humans is consumed water and food. Some mineral elements are ubiquitous, while others are found less frequently and in smaller quantities. Nowadays, given the disturbed ecology, best source may be dietary supplements (biologically active additives) and purified mineralized water.
Different foods contain different amounts of minerals. So, for example, in cow's milk and dairy products contain more than 20 different minerals, the most important of which are iron, manganese, fluorine, zinc, and iodine. Meat and meat products contain microelements such as silver, titanium, copper, zinc, and marine products - iodine, fluorine, nickel.
Diseases caused by a lack of minerals most often occur in certain regions of the globe, where, due to geological features, the natural concentration of a particular microelement is lower than in other areas. The so-called endemic zones of iodine deficiency are well known, in which such a disease as Goiter often occurs - a consequence of iodine deficiency.
However, much more often, a deficiency of minerals in the body occurs due to improper (unbalanced) nutrition, as well as during certain periods of life and in certain physiological and pathological conditions, when the need for minerals increases (the period of growth in children, pregnancy, breastfeeding, various acute and chronic diseases, menopause, etc.).
Potassium– is the main ion of the intracellular environment. Its concentration in the blood is many times less than inside cells. This fact is very important for the normal functioning of body cells. Like sodium, potassium is involved in the regulation of electrical activity of organs and tissues.
The main source of potassium for humans is fresh vegetables and fruits.
Calcium. The total mass of calcium in the adult human body is approximately 4 kilograms. Moreover, its main part is concentrated in bone tissue. Salts of calcium and phosphoric acid are the mineral basis of bones. In addition to minerals, bones also contain a certain amount of proteins, which form a kind of network on which mineral salts are deposited. Proteins give bones flexibility and elasticity, and mineral salts give them hardness and rigidity. Several grams of calcium are found in various organs and tissues. Here calcium plays the role of a regulator of intracellular processes. For example, calcium is involved in the mechanisms of nerve impulse transmission from one nerve cell to another, it participates in the mechanism of contraction of muscles and heart, etc.
The main source of calcium for humans is animal products. Dairy products are especially rich in calcium.
Phosphorus (P) - intracellular enzyme. The element phosphorus is necessary for the normal functioning of the central nervous system.
Biological significance of phosphorus
Phosphorus compounds are present in every cell of the body and are involved in almost all physiological chemical reactions. Phosphorus P enters the human body with food. Phosphorus is found in the following foods: fish, meat, poultry, unrefined grains, eggs, nuts, seeds.
A sufficient amount of calcium and vitamin D in the body is important for the proper functioning of phosphorus. The ratio of Ca (calcium) and phosphorus (P) should be two to one. An excess of iron, aluminum and magnesium makes the effect of phosphorus ineffective.
Magnesium (Mg, Magnesium)- an active intracellular element, part of a number of enzymes. Magnesium is also found in red blood cells, muscles, liver and other organs and tissues. The element magnesium is most necessary for the functioning of the heart, nerve and muscle tissue. Many vital processes of the body depend on magnesium content.
Magnesium in foods is found in lemons, grapefruits, figs, nuts, seeds, dark green vegetables, apples. Magnesium from foods may not be absorbed when taking alcohol or diuretics, oral contraceptives and estrogens.
Many elements in the form of mineral salts, ions, complex compounds and organic matter They are part of living matter and are essential nutrients that must be consumed daily in food. The content of minerals in basic food products is given in table. 5.1.
In accordance with the recommendation of the Dietetic Commission of the US National Academy, the daily intake of chemical elements from food should be at a certain level (Table 5.2). The same number of chemical elements must be excreted from the body every day, since their content in it is relatively constant.
The role of minerals in the human body is extremely diverse, despite the fact that they are not an essential component of nutrition. Minerals are contained in protoplasm and biological fluids, play a major role in ensuring the constancy of osmotic pressure, which is a necessary condition for the normal functioning of cells and tissues. They are part of complex organic compounds (for example, hemoglobin, hormones, enzymes) and are a plastic material for building bone and dental tissue. In the form of ions, minerals participate in the transmission of nerve impulses, ensure blood clotting and other physiological processes body.
Depending on the amount of minerals in the human body and food products, they are divided into macro- and microelements. Thus, if the mass fraction of an element in the body exceeds 10–2%, then it should be considered a macroelement. Proportion of microelements in the body
Table 5.1. Mineral composition of basic food products [according to I.M. Skurikhina, M.H. Volgareva " Chemical composition food products", 1987]
Table 5.2. Daily intake of chemical elements into the human body (in mg) [YU. N. Kukushkin. Chemical elements in the human body, 1998]
is 10 –3 –10 –5%. If the content of an element is below 10 5%, it is considered an ultramicroelement. Macroelements include potassium, sodium, calcium, magnesium, phosphorus, chlorine and sulfur. They are contained in quantities measured in hundreds and tens of milligrams per 100 g of tissue or food product. Microelements are part of the body's tissues in concentrations expressed in tenths, hundredths and thousandths of a millifam and are necessary for its normal functioning. Microelements are conventionally divided into two groups: absolutely or vitally necessary (cobalt, iron, copper, zinc, manganese, iodine, bromine, fluorine) and the so-called probably essential (aluminum, strontium, molybdenum, selenium, nickel, vanadium and some others). Microelements are called vital if their absence or deficiency disrupts the normal functioning of the body. A characteristic feature the necessary element is a bell-shaped curve of the body's response to the dose of the element (Fig. 5.1).
With a small intake of this element, significant damage is caused to the body. He functions on the edge of survival. This is mainly due to a decrease in the activity of enzymes that contain this element. As the dose of the element increases, the response increases and reaches the norm (represented as a plateau on the curve). With further increase in dose, it appears toxic effect excess of this element, as a result of which death cannot be ruled out.
The distribution of microelements in the body depends on their chemical properties and very diverse. Iron, for example, is a compound
Rice. 5.1. Response Dependency (R) from dose ( n) vital necessary elements
part of hemoglobin, myoglobin and other respiratory pigments, that is, substances involved in the absorption and transport of oxygen to all tissues of the body; copper atoms are included in the active center of a number of enzymes, etc.
The effect of microelements can also be indirect – through their influence on the intensity or nature of metabolism. Thus, some microelements (for example, manganese, zinc, iodine) affect growth, and their insufficient intake from food inhibits normal growth. physical development child. Other microelements (for example, molybdenum, copper, manganese) take part in reproductive function, and their deficiency in the body negatively affects this aspect of human life.
To the most deficient minerals in the diet modern man include calcium and iron, excess - sodium and phosphorus.
A deficiency or excess of any mineral substances in the diet causes a disturbance in the metabolism of proteins, fats, carbohydrates, and vitamins, which leads to the development of a number of diseases. Below are the characteristic (typical) symptoms of a deficiency of various chemical elements in the human body:
The most common consequence of a mismatch in the amount of calcium and phosphorus in the diet is dental caries and bone loss. With a lack of fluoride in drinking water is destroyed tooth enamel, iodine deficiency in food and water leads to thyroid diseases. Thus, minerals are very important for the elimination and prevention of a number of diseases.
Let us list the causes of disturbances in the metabolism of mineral substances, which can occur even with their sufficient quantity in food:
A) unbalanced diet(insufficient or excessive amounts of proteins, fats, carbohydrates, vitamins, etc.);
b) application of methods culinary processing food products that cause loss of minerals, for example, when defrosting (in hot water) meat, fish, or when removing decoctions of vegetables and fruits, where soluble salts pass;
c) lack of timely correction of the composition of diets when the body’s need for minerals changes due to physiological reasons. For example, people working in conditions elevated temperature external environment, the need for potassium, sodium, chlorine and other minerals increases due to the fact that most of them are excreted from the body through sweat;
d) disruption of the absorption of minerals in the gastrointestinal tract or increased fluid loss (for example, blood loss).
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