Throughout the entire life metabolic processes take place in human body continuously. The main source of essential body construction materials and energy is nutrients coming from the external environment, basically with food. If a person doesn’t consume food, he feels hungry. Unfortunately, hunger doesn’t tell you what nutrients and in what quantities you need and. And with the development of technological processes, we tend to prefer products that are cooked quickly, paying less attention to its composition and long-term impact on the body.
A healthy diet is the daily ration providing sufficient in quantity and quality in full, satisfying energy, plastic and other needs of the body and providing the necessary level of metabolism. Nutrition plans are built taking into account gender, age, nature of work, climatic conditions, as well as national and individual characteristics.
The principles of a healthy, balanced diet are:
1) compliance of calories entering the human body with food with the consumption of energy;
2) consumption of nutrients in optimal ratios;
3) correct diet in terms of timing;
4) a variety of foods;
5) exclusion of overeating.
Adverse consequences of excess supply on the background of low physical activity suggest that one of the basic principles of good nutrition in intellectual work should be to reduce the caloric value of foods produced to the level of energy expenditure or increase physical activity to the level of caloric intake.
The biological value of food is determined by the content of essential nutrients – protein, fat, carbohydrates and vitamins, mineral salts. For normal human activity not only an adequate supply of nutrients is required, but also the compliance with certain relationships between many factors of food consumption is needed to be taken into account, each of which belongs to a specific role in metabolism. The nutrition characterized by an optimal ratio of nutrients is referred to as balanced nutrition. A balanced diet involves the optimum ratio for a human body in the daily diet of proteins, amino acids, fats, fatty acids, carbohydrates and vitamins.
According to the formula of a balanced diet, the ratio of proteins, fats and carbohydrates should equal 1: 1.2 : 4.6. The number of proteins in the diet composition should be 11 – 13% of daily caloric intake, fat – 33% (in southern regions – 27 – 28%, in northern – 38 – 40%), carbohydrates – about 55%. The sources of nutrients are foods of animal and plant origin, which is conventionally divided into several main groups.
The first group includes milk and milk products (cheese, cheese, yogurt, cream, etc.); the second one – meat, poultry, fish, eggs and products made from them; the third one – bread, pasta and bakery products, cereals, sugar and potatoes; the fourth one – fats; the fifth one – vegetables, fruits, berries, herbs; and the sixth one – spices, tea, coffee and cocoa. Each product group, being unique in its composition, is involved in the preferential supply of the organism certain substances. Therefore, one of the basic rules of a balanced diet is variety. Even if a person sticks to some medicinal diet, using a wide range of plant foods can provide the body with almost everything it needs.
There is no such a product in nature that contains a comprehensive set of all the nutrients essential for the human body (perhaps, with the exception of mother’s milk). With a diverse diet, that is, a mixed diet consisting of animal and vegetable products, human body usually receives enough nutrients. A variety of foods in the diet has a positive effect on its nutritional value, as different products complement the missing components in each other. In addition, a varied diet promotes better digestion.
A well-balanced diet includes multiplicity of food intakes and meal times during the day to promote a proper distribution of its caloric composition and volume. A healthy diet partially depends on the agenda, the nature of work and the climatic conditions. For normal digestion regularity is a key parameter. If a person takes the food at the same time, then a reflex allocation of gastric juice takes place, providing better conditions for its digestion.
It is important that the intervals between meals do not exceed 4-5 hours (4 food intakes daily is an optimal schedule) At the same time food intake for breakfast accounts for 25% of the daily caloric intake, 35% for dinner, 15% for lunch, and 25% for supper. Violation of diet negatively and oftentimes immediately affects your health. It may be manifested with a decrease in the number of meals a day from 4 – 5 to 2, incorrect distribution of the daily diet reaching 65% of total calories per intake instead of 25% and an increase in the intervals between meals from 4 – 5 to 7 – 8 hours.