Proteins

To determine the energy balance, first of all, it is necessary to determine the energy value( caloric content) of the products coming from the food and the energy costs. The energy value of nutrition is calculated using the appropriate coefficients, which are established on the basis of the definition of combustion in the body of nutrients - proteins, fats and carbohydrates.

Proteins ( proteins) are involved in many biological processes occurring in the human body. Proteins are the main building material for the body and make up 15-20% of body weight. In nature, there is a huge variety of proteins. Only in the human body there are about five million different proteins. In general, the cells of the body are constructed from proteins - they are protoplasm, membranes, organoids and intercellular substance. Molecules of protein, having a different structure, perform a variety of functions in the body. For example, they play an important role in the formation of humoral immunity, iron metabolism, atherogenesis and inflammatory processes.

The protein consists of carbon, oxygen, nitrogen and hydrogen. Some proteins also contain sulfur and phosphorus.
Proteins are considered to be biologically complete if they contain a complete set of amino acids, including essential ones. Such proteins are found in animal food and only in certain food plants, such as soy, peas, beans. If you take the biological value of milk proteins for 100, then the biological value of meat and fish will be 95, rye bread - 75, rice - 58, wheat bread - 50. Therefore, in order to increase the biological value, an essential amino acid lysine is added to the bread.

The ideal protein, both in composition and in the content of amino acids in it, is a whole egg hen's egg. Proceeding from this, the percentage of each amino acid of the protein is compared with the corresponding value of the chicken egg. If the ratio of amino acid to its content in the egg protein was determined in a smaller amount, then it needs to be restored in the first place.

The correct balance of proteins in the body is significantly affected by a balanced diet. On the life of the human body, the protein deficit in food is hard to affect. First of all, there is a violation of the nitrogen balance - there is a breakdown of the protein, which predominates over its synthesis. The body, when it lacks protein, begins to "eat" its own tissues, so that this does not happen, you need to constantly enter the body with the food required amount of protein.

Pregnant women( in the period of 5-9 months) need to get an average of 100 g of protein, of which - 60 g of animal origin. Nursing women need to get on average 112 grams of protein, including 67 grams of animal origin.

Food of animal origin is the main source of biologically valuable protein.

In the body, protein deficiency occurs if the food lacks protein either in absolute amounts, or because the body's protein needs are overstated. This can happen either in cases of illness, or during heavy physical work.

With a deficiency of protein in the body, the body's resistance to infections decreases, as a result of a decrease in the level of antibody formation, which ensures the organism's immunity to microbes. There is a violation of synthesis and other protective antimicrobial factors - lysozyme and interferon. There is an exacerbation of inflammatory processes, tk.in these conditions, pathogens begin to behave more aggressively. Adverse effect is the lack of protein in the body on the activities of the cardiovascular, respiratory and other systems. When protein deficiency in the body deteriorates appetite, which in turn, reduces the intake of protein from food, and a vicious circle.

Materials used:
Shilov V.N., Mits'yo V.P."Healthy Nutrition"