Nutrition is an integral part of metabolism, a necessary condition for normal growth, development and vital activity of the body.
Nutrition is the process of entering the body and assimilation of substances necessary for ensuring vital functions.
For the normal functioning of the human body, it is necessary that it constantly receive organic substances (proteins, fats, carbohydrates and vitamins), as well as water and mineral salts. A person receives all the necessary substances from plant and animal food.
Adequate nutrition provides for the correspondence of energy costs to their replenishment. The average daily requirement for proteins is approximately 100-150 g (at least 40 g), for carbohydrates – 400-500 g and for fats – about 80-100 g.
Proteins are an important part of human nutrition. They are the main building blocks of cells. The composition of the proteins of the human body includes about 20 types of amino acids (some of them are irreplaceable, that is, they cannot be synthesized in the human body).
The main sources of protein are meat and dairy products, fish, eggs, nuts, and legumes.
In animal products – meat, fish, eggs, milk – the amino acid composition meets the needs of the body. Vegetable proteins do not contain all the essential amino acids and are not complete. This should be remembered for those people who prefer a vegetarian diet. To provide the body with complete proteins, you need to choose the right foods.
Our body receives fats from products of both animal origin (meat, butter) and vegetable (various vegetable oils). In the cells of our body, fats serve as a building material – cell membranes are formed from them. They also perform storage and energy functions in the body.
It is necessary that the food contains both animal and vegetable fats. Only liquid fats contain unsaturated fatty acids, which are necessary for the normal functioning of the body.
We get carbohydrates (glucose, fructose, starch and others) mainly from plant products: from potatoes, bread, cereals, berries and fruits. Carbohydrates are the main source of energy.
A person needs vitamins in small quantities for the normal course of life processes. These substances are found in foods of plant and animal origin.
Mineral salts are also necessary for the normal functioning of our body. Salts are involved in metabolic processes. They are necessary for the normal functioning of the nervous and muscle tissues. Calcium salts affect blood clotting. A large amount of salt is found in bones and teeth.
Mineral salts enter our body with different foods.
Water is part of every cell in our body. It makes up the bulk of blood plasma, lymph and tissue fluid, digestive juices. Our body is about 2/3 water. For normal life, it is necessary that the flow of water covers its consumption. We get water from food and drink.