What is the correct balanced diet? For life, a person needs about fifty different substances. These are unsaturated fats; eight kinds of amino acids that make up proteins; vitamins (12 species); carbohydrates; cellulose; of the order of fifteen macro- and microelements. The question of proper nutrition is the question of the proportions and quantities in which all this should be consumed by man.
The relationship between proteins, fats and carbohydrates directly depends on what kind of lifestyle people lead. For those engaged in mental work in combination with physical exercises, this ratio is 1: 1: 4; for people of manual labor - 1: 1: 5; for the leading inactive way of life - 1: 0,9: 3,2. The preponderance of carbohydrates is explained by the fact that it is from carbohydrates that the body receives 56% of the energy that food gives us; 30% of energy is given by fats; and only 14% are proteins. At the same time, proteins are the basic building material for the body, so the organism suffers a particularly difficult shortage of protein or its individual elements (amino acids) with improper nutrition.
But all this theory is a thing that is difficult to apply in practice, because it is very difficult to "translate" real food in the form of soups, steaks, cutlets and salads into some amino acids, fats and carbohydrates. It is for most of the "normal" people who are unable to even roughly estimate the amount of nutrients in the eaten dinner, that scientists have developed a simple and intuitive image called the food pyramid.
In 1992, the American Department of Agriculture published several rules for balanced nutrition, which were illustrated in the form of a pyramid. At the base of the pyramid are cereals and other cereals (the main supplier of carbohydrates). On the second tier of the pyramid - vegetables (which are larger), fruits (which are smaller), then - sources of protein (dairy products, fish, meat, legumes). The top of the pyramid is fats and sweets, which were designated as an "optional element of the program." The approximate number of different products was indicated in the pyramid. For example, on the day it was recommended to eat two or four apples or a cup of dried fruits, two eggs, half a cup of nuts, and then in the same spirit.
This pyramid lasted little more than a dozen years and "collapsed" in 2005, when specialists from the same department revised their previous views on the problem of a balanced diet.
The main message of the new concept is that in the problem of nutrition to different people one can not fit with one measure. What is suitable for a young athlete is hardly good for a pregnant lady. That is why in the new "pyramid" there are no exact quantities of masses and volumes - only general recommendations. As recommendations under the pyramid are approximate volumes of products per day, calculated for a certain "average" person who consumes 2000 calories a day, is not burdened with special physical loads, does not suffer from diseases such as lactase deficiency, and is also not a vegetarian.
In addition, the view on fats was revised. If before fats were considered a harmful element, now they say how important it is to consume polyunsaturated fats, which are contained in fish, linseed and olive oil. It is recommended to limit the use of solid fats, completely exclude trans fats.
Cereals for a balanced diet (about 170g per day) should at least be half complete (not steamed and not peeled). Vegetables (about 2½ cups) should be in the bulk orange and dark green, fruit (2 cups) should be simply diverse. Fruit juices, as studies have shown, bring little benefit, in addition, they have a lot of sugar. Milk and dairy products (3 cups per day) are recommended to be consumed as low as possible in fat. The same requirement for meat (160g per day). It is even better to replace meat with fish, nuts, beans, and various seeds.
The main difference between the new "pyramid" and its previous model is that a man is climbing to the top of the pyramid along its smooth walls. This is a symbol of the need for physical exertion for everyone who wishes health.