Rational Nutrition can calculates daily need of proteins, fat, carbohydrates, energy, primary vitamins and minerals for adult people.

In contemporary conception the daily human need of the primary nutritive material (proteins, fats, carbohydrates) depend on total caloric content of food. So, part of fats amounts 30% of total caloric content, part of proteins - 14%, part of carbohydrates - 56%. If caloric content greater than 4000 kcal protein content must by 1% lowers, whereas carbohydrates content must by 1% increases for each 1000 kcal. Total caloric content depend on human power imputs, that depend on normal body weight and physical activity. Body weight calculates by Brok formula.