Effect of human breast milk on biological metabolism in infants.

The metabolic changes that occur during the postnatal weaning period appear to be particularly important for future health, and human breast milk is considered to provide the optimal source of nutrition for infants. Our previous studies examined the effect of feeding type on antioxidative properties, glucose and insulin metabolism, the lipid profile, metabolomics, and prostaglandin (PG) metabolism in term and preterm infants. A urinary marker of oxidative DNA damage (8-hydroxy-2'-deoxyguanosine) was significantly lower in breast-fed term and preterm infants than in formula-fed infants. Markers of insulin sensitivity were significantly lower and atherosclerotic indices were significantly higher in breast-fed preterm infants than in mixed-fed infants at discharge. On urinary metabolomics analysis, choline, choline metabolites, and lactic acid were significantly lower in breast-fed term infants than in formula-fed infants. Urinary PGD2 metabolite level in breast-fed term infants was also significantly lower than in formula-fed term infants. This indicates that human breast milk affects biological metabolism in early infancy.