The physiology of nutrition. Fundamentals of the physiology of nutrition

Food is one of the main components of the health, activity and quality of life of a person as a whole. But, in order for all these components to be realized, it is necessary to supply the body in a timely manner with certain substances in the correct ratio and volume. The physiology of nutrition studies the composition of a person's diet: how much protein does he need, fat, carbohydrates, vitamins and minerals for optimal functioning. Also this branch of science focuses on the ways and time of food intake, its volume and physical properties.

Carbohydrates

The physiology of human nutrition gives carbohydrates a leading role in energy metabolism. Thanks to them, the individual quickly gets a supply of strength and energy, including for mental activity. Carbohydrates perform several more important functions:

• Plastic (are part of the tissues of various organs);
• Regulatory (in the oxidation of fats are not allowed to accumulate ketones);
• Tonic (activate the processes in the nervous system);
• Detoxification (remove harmful chemicals).

According to the chemical structure, the ratio of hydrogen and oxygen atoms is similar to water molecules.

In food products are found carbohydrates of three types:

• Monosaccharide compounds (represented by glucose and fructose);
• Oligosaccharide compounds (represented by sucrose, lactose and maltose);
• Polysaccharide compounds (represented by starch, glycogen, cellulose and pectin substances).

Sources of carbohydrates - is primarily food of plant origin: fruits, vegetables, cereals, etc.

Fats

Fundamentals of physiology and nutrition hygiene contain a section on fats as the main food components, since their energy value is twice as high as that of proteins and carbohydrates. Lipids are part of the cell structure and are involved in the construction processes.

Only in the presence of fats is the dissolution and assimilation of vitamins A, D and E. In lipid compounds are present biologically active substances: tocopherol, lecithin, polyunsaturated fatty acids, sterol. Improving the taste of food and increasing its nutritional value is possible due to the addition of fats.

Fats in food are, in essence, essential compounds of glycerin and fatty acids. The latter are divided into two subgroups: saturated and unsaturated. The physiology of nutrition assigns a large biological significance to polyunsaturated fatty acids, equating them to vitamins.

Lipids in animal nutrition are represented by saturated fatty acids (pork, beef, lamb, etc.), in vegetable - unsaturated (oils, nuts, seeds).

Proteins

Fundamentals of the physiology of nutrition designate proteins as a necessary condition of life. Of these, all cells and tissues are built in the human body. Functions of proteins are diverse: plastic, catalytic, reproducing, protective, antitoxic, transport and others.

By chemical structure, proteins are complex nitrogenous polymers consisting of amino acids, 25 of which are represented in food. Most of them are reproduced by the body (replaceable), some come exclusively with food (irreplaceable).

Hygiene and physiology of nutrition take into account the importance of protein products, especially those in which full proteins are present, with a balanced amino acid composition. The most suitable in this regard are products of animal origin (meat, eggs, milk). Proteins of plants are most often deficient in a complex of essential amino acids (soy, buckwheat, beans, bran, etc.).

Macronutrients

Fundamentals of the physiology of nutrition consider macronutrients as substances necessary for normal vital activity of the organism, participating in metabolic processes of various levels. These substances are especially important for building bones that need calcium and phosphorus.

The macronutrients include:

• Calcium (milk, cheese, cottage cheese);
• Phosphorus (fish, meat, bread, cheese, beans, cereals);
• Magnesium (bread, cereals, beans, nuts);
• Sodium (table salt);
• Potassium (potatoes, apples, beans, peas);
• Chlorine (bread, salt);
• Sulfur (meat, fish, eggs).

Deficiency of macroelements leads to various diseases of organs and systems, first of all the bones and blood vessels suffer.

Trace Elements

Microelements perform a number of specific functions, ensuring the optimal functioning of the organism as a whole and its individual organs.

The group of microelements include:

• Iron (liver of animals, buckwheat groats);
• Zinc (liver, beans);
• Iodine (sea kale, cod liver, sea fish);
• Fluorine (sea fish, water, teas).

The physiology of nutrition is focused on the organization of a diet with a sufficient number of macro- and microelements necessary for maintaining health.

Vitamins

In the textbook "Biology. Physiology of Nutrition »(Grade 7), information on vitamins is presented in several sections. Their role for the life of the body is difficult to overestimate. These active substances are present in enzymes and hormones, participate in metabolic processes, ensure coherence in the work of organs and systems.

Vitamins are not produced by the body, so their intake with food is important. Deficiency leads to the appearance of diseases, increased fatigue, reduced efficiency and immunity.

A balanced diet should contain the following vitamins:

• A - maintains health and youthfulness of the skin, visual acuity, immunity (sources: carrots, eggs, milk, herring, liver);
• B ₁ - provides the functioning of muscle and nerve fibers, energy production (sources: rice, meat, legumes, nuts);
• B ₂ - activates growth and energy metabolism (sources: egg yolk, poultry, fish, yeast);
• B ₆ - helps to assimilate carbohydrates and fats, supports enzymatic reactions (sources: potatoes, fish, meat, grain bread, vegetables);
• B ₁₂ - prevents anemia, disorders in the nervous system (sources: seafood, milk, meat, eggs);
• C - supports immunity, health of teeth, skin and bones (sources: oranges, lemons, black currants, dogrose, sweet peppers);
• D - promotes the absorption of calcium, the growth of teeth and nails (sources: fatty fish, dairy products);
• E - protects the body from oxidation at the cellular level, promotes the regeneration of the skin (sources: meat, vegetable oils, cereals).

The physiology of nutrition implies the intake of vitamins in the form of special complexes, developed taking into account the age and lifestyle of a person.

Food Hygiene

In addition to taking into account the microbiological composition of products, the physiology of nutrition - sanitation and the hygiene of eating behavior. Its principles can be presented in the form of the following rules:

1. The diet should be as varied as possible.
2. Every day several times you need to eat foods from flour, cereals or potatoes.
3. Regular physical activity is desirable.
4. It is necessary to eat fresh fruits and vegetables daily.
5. It is necessary to keep a constant record of fats with food, it is desirable to replace the animal with a vegetable.
6. Limit the use of refined sugar.
7. Do not abuse the addition of salt in the dish.

Food preparation should ensure safety and maximum preservation of the useful properties of the products (preferably cooking, including steaming, baking, microwave cooking).

Compliance with these simple rules will improve the quality of food.

Food production

Another important question, which is concerned with the physiology of nutrition, is the technology of food production. Ideally, industrial conditions should be organized in such a way that the nutritional value of the raw material base is increased. The ultimate utility of the product will be determined not only by the content of nutrients, but also by the extent to which they can be absorbed by the body. This problem is associated with both digestion and with a number of other physiological processes.

Despite all the difficulties, it is reliably established that quality food is digested much better than made from unnatural and stale raw materials. The more delicious and appetizing the food, the more useful it will be for the body. This fact must be taken into account in the process of food production.

Basics of sanitation

The content of proteins, fats, carbohydrates, vitamins and minerals is examined by microbiology, the physiology of nutrition. Sanitation is focused on the development of rules for personal hygiene in the preparation and consumption of food. They prevent contamination of products, entering into them pathogens of infections that provoke food poisoning and a number of diseases.

Particular attention is paid to the sanitary conditions of cooking in public catering establishments. The high level of personal hygiene of workers influences the culture of interaction with consumers.

The rules of individual health procedures provide for certain requirements for the condition of the hands, mouth, overalls, the conditions of the organization, regular medical examination of employees.

Personal hygiene of each person at meals implies thorough washing of hands, and, if necessary, the whole body, the purity of clothes, the use of an individual set of dishes. In the presence of infectious diseases, contacts with other persons should be limited.

Nutrition physiology as a scientific discipline

The discipline "Nutrition physiology" is taught in compressed form in secondary schools, and is deployed in professional educational institutions. It includes the study of physiological systems related to nutrition, ecological and medical features of human nutrition, the basis of digestion. A significant part of the classes is devoted to the study of nutrients, principles of rationing, hygiene and sanitation in the preparation, processing and storage of products. The physiology of nutrition with the basics of commodity science is the final thematic block that encompasses the economic component of the problem.