Observations on the adequacy of breast-feeding

Abstract

The faltering of growth which frequently occurs in babies at the age of about 3 months in developing countries is sometimes attributed to insufficient food or to increased exposure to infection. The adequacy of breast-milk as a sole source of food for the young infant is examined in relation to the calculated average requirements for protein and energy. It is concluded that breast milk will fail to cover the energy needs of many infants after about 3 months unless a regulatory mechanism permits infants with higher than average requirements to obtain larger amounts of milk.

PIP: This paper examines the length of time breastfeeding is expected to be nutritionally sufficient for the healthy infant and whether breastmilk is sufficient as the sole food source for 4-6 months or longer. The body's absolute requirement for energy increases with age more rapidly than that for protein because the maintenance requirement is larger than that needed for growth. It seems that with average intakes of breastmilk, the protein requirement from the 2nd month month onward will just be met even in the 6th month; energy becomes limiting. Generally, intake is inadequate by the 4th month. The authors contend that estimates about average breastmilk output are low; Wallgren's estimate of 700 ml/day rising to 800 ml/day by the 3rd month compares well with other estimates. Energy requirements are based on the 25th percentile weights of the North American reference population with the largest component being for maintenance, 80 kcal/kg body weight. These physiological estimates are in line with standard pediatric practice and seem likewise to be in line with observed intakes of bottlefed infants.