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Nutrition and essential nutrients


The most important condition for nutrition is the correct combination of all the nutrients in the daily ration of a person; moreover, they must be introduced in quantities that completely cover all body wastes both in quantitative and qualitative terms.
In the human body, oxidation processes (combining with oxygen) of various food substances - proteins, fats, carbohydrates - are continuously carried out, which are accompanied by the formation and release of heat. This heat is necessary for all life processes, it is spent on heating the inhaled air, to maintain body temperature. Thermal energy also provides the activity of the muscular system. The more muscle movements a person performs, the more he produces losses, which require more food to cover.
The need for more food is expressed in heat units - calories. At present, according to the international measurement system (SI), the energy value of food is expressed in joules (1 kcal = 4.184 kJ). The caloric content of food is the amount of energy that is formed in the body as a result of the absorption of food. A calorie is the amount of heat that is needed to heat 1 liter (large calorie) and 1 ml (calorie) of water having a temperature of 15 degrees Celsius, one degree. Each gram of protein and each gram of carbohydrates of any food, when burned in the body (during oxidation), forms heat, equal in quantity to 4 kcal, and when burning 1 g of fat, 9 kcal is formed. Knowing the magnitude of the need for energy, it is possible to determine the need for essential nutrients - proteins, fats and carbohydrates. Important for the life of the body are also minerals, vitamins and water. Squirrels.
Proteins are of particular importance in nutrition. The main manifestations of life are connected with their action: metabolism, muscle contraction,
nerve irritability, ability to grow and reproduce, and even thinking. They are contained in all tissues and body fluids, being their main component. Proteins are composed of various amino acids that determine their biological significance. Some of the amino acids are formed in the body. They are called interchangeable amino acids. Others enter the body only with food. These amino acids are called essential amino acids. For a physiologically full-fledged vital activity of the body, it is necessary to have all the essential amino acids in food. Insufficient content in the food of at least one essential amino acid leads to a decrease in the biological value of proteins and may be the cause of protein deficiency, despite the sufficient amount of protein in the diet. Essential amino acids are mainly found in products of animal origin: in milk, cottage cheese, meat, fish, eggs.
However, the human body can not do without proteins of plant origin, which are contained in bread, cereals and vegetables, which are mainly composed of essential amino acids. Proteins of animal products in combination with proteins of plant origin provide the body with substances necessary for its development and vital activity.
An average human body needs about 1-1.2 g of protein per 1 kg of body weight. This means that a person weighing 70-75 kg should receive from 70 to 90 g of protein per day.

If the intensity of physical labor increases, so does the body's need for protein. The average daily rate of an adult human protein is considered to be 90-100 g per day, moreover, 55% of it should be provided by animal protein.
The most important sources of protein are meat, fish, eggs, cheese, milk, bread, potatoes, beans, soybeans, peas.
Proteins in the diet can not be replaced by any other substances. Fat
The physiological significance of fats is very diverse. They are a source of energy and surpass the energy of all other substances. Fats are involved in regenerative processes, being a structural part of cells and their membrane systems; serve as solvents of vitamins A, E, D and promote their absorption. Improving the taste properties of food, fats increase its nutritional value. In addition, they contribute to the development of immunity and help the body to keep warm.
Inadequate intake of fat in the body can lead to disruption of the central nervous system, changes in the skin, kidneys, organs of vision, etc. Animals that received a fat-free diet were less durable and longer in life.
The composition of fat and its attendant substances revealed such vital components of nutrition as polyunsaturated fatty acids, lecithin, vitamins A, E, etc.
The average need for an adult in fat is 80-100 g per day, including vegetable - 25-30 g.
In food, at the expense of fat, 33% of the daily energy value of the diet should be provided, which according to modern data is optimal. Per 1000 kcal accounts for 37 g of fat.

Adequate fats are found in foods such as brains, hearts, eggs, liver, butter, cheese, meat, lard, poultry, fish, milk. Vegetable fats are also valuable, especially in the nutrition of the elderly, as they do not contain cholesterol. Carbohydrates.
Carbohydrates are the main source of energy. On average, they account for 50 to 70% of the daily caloric intake. Each gram of carbohydrate provides 4 kcal of energy. The need for carbohydrates depends on the energy waste of the body.
For people engaged in mental or light physical labor, the daily need ranges from 300 to 500 g. For those who are engaged in physical labor and athletes, it is much higher. Inclined to fat, you can reduce the amount of carbohydrates in the diet without compromising health.
Vegetable products are the richest in carbohydrates - bread, cereals, pasta, potatoes. Pure carbohydrate is sugar.
Excessive amounts of carbohydrates violate the correct ratio of the main parts of the food, which, in turn, leads to metabolic disorders. Vitamins.
Vitamins are substances that do not supply the body with energy, but are absolutely necessary in minimum quantities to sustain life.
They are irreplaceable, because they are not synthesized or almost not synthesized, they are not produced by the cells of the body. Vitamins come or with food, which contains, or in the form of synthetic drugs. They regulate, direct and accelerate metabolic processes.
Vitamins are divided into two large groups: water soluble and lipid soluble.
The group of fat-soluble vitamins include vitamins A, D, E, K.

Vitamin A affects the growth of the body, its resistance to infections. It is necessary to maintain normal vision, condition of the skin and mucous membranes. Contains vitamin A in large quantities in fish oil, cream, butter, egg yolk, liver. Some vegetable products: carrots, lettuce, spinach, tomatoes, green peas, apricots, oranges - contains carotene - provitamin A, which in the body turns into vitamin A.
Vitamin D promotes bone formation and stimulates the growth of the body. With a lack of vitamin D in food, the body’s normal absorption of calcium and phosphorus is disturbed, leading to rickets. The greatest amount of vitamin D is found in fish oil, egg yolk, liver, and fish eggs. Vitamin D is found in milk and butter in a small amount.
Vitamin K is involved in tissue respiration, contributes to the preservation of normal blood clotting. This vitamin is synthesized in the body by intestinal bacteria. Lack of it may occur when diseases of the digestive system or when taking various antibacterial drugs. Vitamin K is found mainly in tomatoes, green parts of plants, spinach, cabbage, nettles.
The group of water-soluble vitamins include vitamin C and vitamins of group B.
Vitamin C, or ascorbic acid, is actively involved in redox processes, affects carbohydrate and protein metabolism, increases the body's resistance to various infections. This vitamin is found in many fresh vegetables and fruits. The richest fruits are wild rose, black currant, black chokeberry, sea buckthorn, gooseberry, citrus fruits, cabbage, potatoes, leafy vegetables.

The group of vitamins B consists of 15 active, water-soluble, independent vitamins that take part in the body's metabolic processes, blood formation, and also plays an important role in carbohydrate, fat and water metabolism. Vitamins of group B are growth promoters. Vitamins of this group are found in beer and baker's yeast, buckwheat and oatmeal, rye bread, milk, meat, liver, egg yolk, green parts of plants.
Vitamin E (tocopherol) refers to fat-soluble vitamins. It affects the activity of the endocrine glands, the metabolism of proteins, carbohydrates, provides intracellular metabolism. Vitamin E has a positive effect on the course of pregnancy and fetal development. Most of this vitamin is found in grains of corn, carrots, cabbage, green peas, eggs, meat and fish products, in cow and olive oil.
Prolonged lack of vitamins in the diet leads to avitaminosis. But more often there are hypovitaminosis, the development of which is associated with a lack of vitamins in food; This is especially observed in the spring and winter months. When hypovitaminosis increases fatigue, there is a weakness, apathy, reduced performance, decreases the body's resistance.
There is a close relationship between the action of individual vitamins. Lack of food in one of the vitamins leads to metabolic other substances; only with proper nutrition vitamins have the proper effect. Minerals.
The food must contain minerals that are part of the cells and tissues of the body and are involved in various metabolic processes. Calcium, potassium, magnesium, phosphorus, chlorine, sodium salts are macroelements, they are needed daily in relatively large quantities, as well as iron, zinc, manganese, chromium, iodine, and fluorine. which are needed in very small quantities, so they are called trace elements. Trace elements enter the human body with products of animal and vegetable origin. For example, iodine is rich in sea foods; zinc is the richest in cereals, yeast, legumes, and liver; Copper and cobalt are found in beef liver, kidneys, chicken egg yolk, honey.
The mineral composition of berries and fruits is very diverse. They have a lot of potassium, iron, copper, phosphorus. And all these minerals are perfectly digested. In addition, they are low-calorie, they lack fats and cholesterol, a lot of vitamin C - all this makes them indispensable in the diet of people suffering from many diseases: hypertension, circulatory disorders, kidney damage, especially with the formation of edema. Potassium contained in these products enhances the excretion of fluids from the body.
Good absorption of food by the body depends on its skillful preparation, appearance, variety of the menu. It is very important what the food looks like, whether the table is beautifully laid. From one pleasant type of dish, gastric juice begins to actively stand out, and the entire digestive system is prepared at the time of eating.
You can not eat very hot and very cold food. The temperature of hot dishes should be no more than 60 degrees, cold - not less than 10 degrees.
In certain diseases, for example, in diabetes, food must contain not only certain foods, but the entire daily diet must have an established chemical composition. It is necessary to observe a certain menu, each dish of which is prepared according to the stipulated norms and with the appropriate culinary processing.
Medical nutrition at home has its own characteristics, because you have to take into account that the patient’s appetite is usually lowered, and the list of products in his menu is limited and condiments are prohibited. Nevertheless, diet food dishes can be very tasty if they are prepared with knowledge of the matter.
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Nutrition and essential nutrients

  1. Nutrition and essential nutrients
    The most important condition for nutrition is the correct combination of all the nutrients in the daily ration of a person; moreover, they must be introduced in quantities that completely cover all body wastes both in quantitative and qualitative terms. In the human body, oxidation processes (combining with oxygen) of various nutrients - proteins, fats, carbohydrates - continuously
  2. Nutrition and essential nutrients
    The most important condition for nutrition is the correct combination of all the nutrients in the daily ration of a person; moreover, they must be introduced in quantities that completely cover all body wastes both in quantitative and qualitative terms. In the human body, oxidation processes (combining with oxygen) of various nutrients - proteins, fats, carbohydrates - continuously
  3. Nutrition and essential nutrients
    The most important condition for nutrition is the correct combination of all nutrients in the daily diet of a person. These substances can be divided into six groups: 1) proteins, 2) fats, 3) carbohydrates, 4) vitamins, 5) minerals, 6) water. They must be introduced in quantities that fully cover all the waste of the body, both in quantitative and qualitative terms. In humans, continuously
  4. Nutrition and biological value of basic foods
    The nutritional value of the product is determined by the content of nutrients (food and taste), the biological value - its amino acid intake, the presence of PUFA, vitamins, mineral salts and other biologically active substances. The main foods are bread, meat and meat products, fish and fish products, milk and dairy products, vegetables, berries, fruits and some others.
  5. The concept of hygienic nutrition. Nutrition norms Food products, their composition and energy value.
    Nutrition is a complex process of receipt, digestion, absorption and assimilation in the body of nutrients necessary to cover its energy expenditure, build and renew cells and tissues of the body, and regulate the body's physiological functions. In hygiene, the term “good nutrition” is adopted, which means a food built on a scientific basis that can fully meet the need for
  6. RECOMMENDED SIZE CONSUMPTION OF FOOD SUBSTANCES
    Each country should use the recommended nutrient consumption values ​​for infants and young children, based on scientific data obtained by the international scientific community, as the basis for their methodological recommendations on nutrition and feeding for children. INTRODUCTION Recommended values ​​are discussed and compared in this and four subsequent chapters.
  7. Carcinogenic chemicals in food
    One of the oldest medical problems is Nutrition and Cancer. This is because food may contain carcinogenic chemicals (CXW) and their precursors. KHV sources primarily belong to industrial waste, thermal power plants, heating systems and transport. Migrating in the atmosphere, in the soil and water bodies, these carcinogens can get into food. Of such
  8. Food substances and their value.
    The human body consists of proteins (19.6%), fats (14.7%), carbohydrates (1%), mineral substances (4.9%), water (58.8%). He constantly spends these substances on the formation of energy necessary for the functioning of internal organs, maintaining heat and the implementation of all life processes, including physical and mental work. 1. Proteins These are complex organic compounds from
  9. Nomenclature of recommended nutrient intake values
    Several countries have adopted their own PRWV systems and use different term education systems (Table 8). The European Union uses population-based reference consumption values ​​(HDPE), and in the former Soviet Union, the term “physiological norms" of the PRWT used in this publication correspond to the reference nutrient intake values ​​shown in
  10. Effect on the body of purified nutrients
    During the whole evolution, the animal's organism consumed only natural food, which, with very few exceptions, was a complex of various substances. It is therefore not surprising that the mechanisms formed in the phylogenesis of metabolism suggest, on the one hand, the intake of the food substance in the natural form created by nature (and not separately proteins, carbohydrates, fats, iron,
  11. Hygienic regulation of harmful substances in the environment and food
    Hygienic regulation is mandatory for all toxic substances entering the human body from the environment - air, water, soil, food, materials in contact with food, etc. Any chemical substance is toxic under certain conditions of exposure. Toxicity - the ability of a substance to cause harm to a living organism. On the human body
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