Nutritional requirements

Normal and Therapeutic Nutrition 3(2+1)
Lesson 12:Nutritional And Food Requirements For Infants

Nutritional requirements

  • During early infancy, much of nutrient requirements are met through breast milk.
  • RDA of infants is based on composition of breast milk.


  • Basal and total energy requirement for infants are higher than adults per unit body weight.
  • An adult requires 40 k cal/kg body weight, whereas infant requires 108 k cal/ kg body weight
  • For a month old infant
  • A child who crawls or walks will not gain weight unless additional calories are supplied for proper growth.
  • About 70% calories can be met by milk alone and rest of calories have to be supplied by introducing supplementary foods after 6 months.


  • Like energy, protein requirements are also higher for infants as compared to adults, due to increased demands for skeletal muscle growth.
  • Protein intake of healthy infants is about 2 gm/ kg body weight.
  • Human milk provides all amino acids more than required for proper growth.
  • Histidine, a non-essential amino acid necessary for growth and maintenance of infant is present in breast milk.
  • Human milk protein is 100% utilized. Protein content of human milk is 1.1g/ 100ml or 6% of total energy.
  • Protein requirement/kg body weight decreases gradually during the first 12 months similar to energy requirement.
  • If protein and energy requirements are not met, infant suffers from Protein Energy Malnutrition (PEM).
  • If excess protein is fed, it is harmful as protein needs to be de-aminated. Infant has a limited capacity to concentrate the waste metabolites as the kidneys are not well developed.

Essential Fatty Acids:

  • Linoleic acid is most important essential fatty acid for an infant.
  • If infants are fed with less fat, they may develop skin lesions, diarrhoea leading to growth retardation. Supplementation with linolenic acid result in disappearance of symptoms.
  • Both cow’s and mother’s milk satisfy requirement of essential fatty acid.

Calcium and phosphorus:

  • Large amount of calcium and phosphorus are required as there is rapid growth
  • At birth bones are poorly calcified. By the time baby walks, calcification of bones should be done to support the weight of the body.
  • If sufficient calcium is not provided motor development is delayed.
  • Calcium: Phosphorus ratio is 2:1 in human milk
  • High phosphorus leads to hypocalcemic neonatal tetany.


  • RDA of iron for an infant is 1 mg/kg body weight from the age of 3 months.
  • At birth infant has stores of 75mg/kg of iron.
  • During first 3 months blood volume doubles and concentration of Hb falls to about half of that present at birth. The infant also doubles his birth weight by 6 months without depending on dietary iron.
  • Low birth weight infant requires supply of dietary iron.
Hypochromic anaemia can occur in infants due to:
  1. Depletion of fetal stores
  2. Greater need for iron during growth
  3. Inadequate dietary supply


  • Zinc is necessary for normal brain development.
  • High levels are present in colostrum and it promotes normal growth.


  • Intake of sodium by breast fed infant is less than 1/3rd of one fed on cow’s milk.
  • Amount of sodium present in human milk is adequate.


  • A pregnant woman with goitre gives birth to infant with cretinism. These children are mentally retarded which is irreversible even after treatment.

Vitamin A:

  • RDA is 350?g. Breast milk contains sufficient amounts of vitamin A.
  • A healthy infant at birth has sufficient stores of vitamin A in liver which will last for 6 months.
  • Excess vitamin A leads to anorexia, hyper irritability, desquamation of skin.

Vitamin D:

  • Very essential for utilization and retention of calcium and phosphorus
  • Neither human nor cow’s milk has vitamin D.
  • RDA is placed between 200- 400 IU of vitamin D/ day. This requirement may be obtained through exposure to sunlight. Avoid large amounts of vitamin D to prevent hypervitaminosis D.

Vitamin E:

  • Food & Nutrition board has prescribed 5 IU of Vitamin E during infancy.
  • Cow’s milk is a poor source of vitamin E

Vitamin K:

  • New born babies are susceptible to haemorrhage. Therefore a single dose of 1 mg of vitamin K immediately after birth will prevent haemorrhage
  • Breast fed baby is more susceptible to vitamin K deficiency than artificially fed infant
  • Excess dosage is harmful.

Vitamin – B complex:

RDA for B vitamin is based on weight of infant which is based on calorie consumption.
If mothers are suffering from thiamine deficiency very little thiamine content is present in breast milk.
Thiamine deficiency in infants leads to

  • Anorexia, vomiting, breathlessness and death may also occur unless treatment with thiamine is given intravenously.

Onset of infantile beri beri is sudden in infants who are healthy. Therefore intramuscular injection of thiamine is given.
If antibiotics are taken by infant, the requirement of vitaminB12 increases.

Vitamin C:

RDA prescribed by ICMR is 25mg.
Human milk contains twice the amount of ascorbic acid in comparison to cow’s milk. But both are not good source of vitamin C.
Less vitamin C is present in breast milk, deficiency of vitamin C in mothers and the infant develops scurvy. Therefore fruit juice should be introduced from 6th month onwards to prevent scurvy.

Last modified: Monday, 24 October 2011, 8:20 AM