Explain Change in body Composition of infants?

The weight gain comprise of growth in the muscle, organ tissue, adipose and skeletal structure. One compartment of body which registers fall is body water. The infant at birth has 75% body water which declines to 60% of the weight by the end of first year. This value is closer to that of an adult. However, these are a tremendous increase in absolute amount of water. Hence, depletion of water due to conditions likes vomiting or diarrhoea can prove to be fatal in infants.

The infants synthesize lean tissue hence there is an increase in body nitrogen from 2% at birth to 3% at first year. The skeletal system continues to gradually increase till adolescence. The infant is born with 12-15% body fat. This rises to 23% at 12 months and declines to 18% at 6 years of age. Hence, there is a net increase in body fat also.