Nutritional Requirements is a dynamic process to supply adequate nourishment for survival, growth & development, repair and creation of future reserves. Weight-wise, nutritional requirements of children are relatively higher than in adults due to active growth, building of stores, higher basal metabolic rate and more pronounced physical activity.
Diet is the main source of Nutritional Requirements in children, though some nutrients i.e. Vitamin D and K are also synthesized endogenously in body. An ideal diet should fulfill requirements of all essential nutrients in adequate proportions and composition.
Although many terms are used in practice to denote dietary needs, often interchangeably, it is important to understand that Nutritional Requirements denote daily physiological requirements of various nutrients to maintain normal metabolism; It includes daily nutritional intake, essential to fulfill abovementioned nutritional requirements, after considering absorption losses.
Recommended dietary allowances (RDA) is defined as the ‘minimum daily dietary requirement of a nutrient in normal healthy person along with some additional allowance for individual variations to cover the needs for 97.5% of healthy (not sick) population, without the risk of over-dosage’.
Energy is the prime essence of Nutritional Requirements, required to sustain basal metabolic rate, day-to-day physical activity, normal growth, and to digest and assimilate the nutrients i.e. specific dynamic action (SDA).
Basal metabolic rate (BMR) i.e. the minimum energy requirement to maintain essential physiological functions of the body at rest, is highest in infancy (55 cal/kg/day) and decreases gradually with advancing age to reach adult values (25-30 callkg/day) in late childhood.
A normal child spends —50% of energy requirements for BMR, 25% for physical activity, 12% for growth, 5% for digestion/assimilation of food and 8% for fecal losses.
Sources: Carbohydrates are the main source of energy in diet. An ideal diet should provide 50-60% of calories as carbohydrates, 20-30% as fats and 10-15% as proteins.
Each gram of Proteins, fats and carbohydrates in diet provide 4, 9 and 4 calories, respectively.
Nutritional Requirements: Energy requirements in normal children vary according to the age, though it may also be calculated according to the body weight by Holiday and Segar formula. It should be noted that these are the requirements for normal and not the malnourished children, who need higher calories for catch-up growth and replacement of stores.