ABSTRACT
Feeding practices related to osmotic strength of bottle-milk and breast-milk were studied in 133 families with infants less than 1 year of age in a poor urban settlement in Brasilia, Brazil. Osmolality [mean (SEM)] of breast-milk [318.8 (4.46) mOsm/kg water] was significantly less than that of bottle-milk [568.7 (29.9) mOsm/kg water]. The wide range of osmotic strength (253.7-1,380.0 mOsm/kg water) found in bottle-milk was partly due to the predominant use (82%) of powdered cow's milk among non-breastfeeders and its improper reconstitution. Diarrhoea and feeding management are also discussed.
PIP: The osmotic strength of breast and bottle milk fed to poor infants in developing countries is of critical significance given the newborn's inability to eliminate a high solute urine. Milk preparations with high osmotic activity have been associated in infants with necrotizing enterocolitis, disturbances in gastric and intestinal motility, and possible effects on gastric emptying and nutrient absorption. As part of a larger study of feeding practices and infant nutritional status in Brazil's squatter village of Paranoa, the osmotic strength of bottle milk and breast milk was studied in 133 families with infants under 1 year of age. Overall, the mean osmolality of breast milk (318.8 mOsm/kg water, range 265-475) was significantly lower than that of bottle milk (568.7 m)sm/kg water, range 253.7-1380). No trend was observed for either type of feed according to the length of lactation or the age of the infant. The wider range of osmotic strength in bottle milk was partly attributable to the predominant use (82%) of powdered cow's milk and its improper reconstitution (i.e., a tendency to overconcentrate during reconstitution). 37% of the infants in this study experienced an episode of diarrhea in the 15 days preceding the interview, with no significant difference in incidence between breastfed and bottlefed infants. Given this high incidence of infantile diarrhea, as well as the high temperature and dryness of the Brazilian climate, health authorities are urged to give greater attention to the potential contribution of solute load in the prevention of dehydration.