We are 20% protein, but nevertheless, every day we need to fill this balance with about 100 g of protein from food. A person spends in the course of life a huge amount of protein stores - blood, enzymes, muscle fibers, regeneration of cells and tissues, all this takes protein, which must be compensated for something. We have only two ways - animals and vegetable proteins, which must be really high quality.
Quality of protein nutrition
Protein nutrition is classified by qualitative composition and rate of assimilation. Thus, vegetable proteins are inferior to animals in both indices.
Animal proteins contain essential amino acids in a full set, vegetable, usually, do not contain one or two essential amino acids. For example, potatoes and legumes do not contain methionine and cysteine, cereals - lysine and threonine. Among plant proteins, the best composition can boast:
- peas;
- soybean;
- beans;
- buckwheat and oatmeal.
The most complete protein is contained in:
- milk;
- fish;
- eggs;
- meat.
By the degree of assimilation, protein nutrition can also be classified:
- meat, fish, egg whites, milk - are absorbed by 90-100%;
- protein from cereals and vegetables - 80%;
- protein from legumes - 70%;
- protein fungi - up to 40%.
Therefore, 60% of the protein in the human diet should be of animal origin.
The role of proteins in human nutrition
Actually, the role of proteins should be assessed not only in human nutrition, but also in all spheres of life. Proteins are the building material for everything new, so if we want the body to successfully renew itself, we need protein. The main functions of proteins:
- proteins directly participate in the structure of any cell of the human body;
- most hormones (insulin, glucagon) and enzymes are proteins;
- the importance of proteins in human nutrition is so high, because these molecules connect all the processes that take place in the body, that is, they are neurotransmitters - transmitters of information from the brain to the cell, from cell to cell;
- proteins transport nutrients through the blood - lipoprotein proteins carry fat, hemoglobin, oxygen, transferrin - iron ;
- the immune value of proteins in ensuring the constant presence of immunoglobulin proteins in the blood - they protect against infections, accelerate the process of blood clotting.
When the protein needs more ...
The fact that protein is a building material, we already know. So in all those cases where the body needs to actively "rebuild", we must consume an increased amount of protein. It:
- period after surgery, surgical interventions, chemotherapy;
- with blood loss, tuberculosis, corticosteroids and antibiotics;
- with diseases of the digestive tract, fractures, burns.
However, the simplest and most harmless is the body's need for protein due to active sports activities. In such cases, you can not do without protein sports nutrition.
Sports nutrition is purified of impurities (carbohydrates, fats, fiber ) proteins that are absorbed quickly not only in nature (like whey protein), but also due to this high-quality cleaning.
Such proteins are intended for athletes in those cases when the necessary amount of protein can not be replenished with a normal diet - they simply would have to eat 7 times a day, and at the same time, by some miracle, not exceeding the total caloric value. Protein from sports nutrition should not be more than 50% of the total amount of protein consumed per day. Sports nutrition should complement, not replace, ordinary food.
However, the excess protein is not more pleasant than the deficit. Therefore, even tasty protein cocktails from sports stores should not be used carelessly, as desserts to anyone, without the real need.