Macronutrients in human milk and infant formula : bioactivity and health effects

Abstract: Human milk has been considered the ultimate food for infants to optimize their growth and development, but it has lately also shown to impact longterm health. Infant formula is the complementary food to neonates who are not breastfed, and its nutrients should mimic human milk as close as possible. Since infant formula mainly is based on cow’s milk, there are several important differences e.g. protein content, and bioactive compounds, that need to be modulated in infant formula. The protein levels in human milk are significantly lower than in cow’s milk. Bioactive compounds found in human milk that are not present in cow’s milk have shown to improve metabolic pathways in the neonate through several mechanism e.g. protection against infections, improving nutrient absorption and benefiting neurological function. Galactooligossacharides (GOS) and fructooligossacharides (FOS) are supplemented to infant formula to compensate human milks high levels of oligosaccharides. Milk fat global membrane (MFGM) and docosahexaenoic acid (DHA) are other constituents that are usually added in infant formulas to benefit infant health. The different outcome of health effects between formula fed and breastfed infants highlight the importance of prevention strategies. The nutrient composition of human milk is complex, however our knowledge expands rapidly and thereby increases the nutritional requirements of infant formula. Long-term studies will have to confirm the beneficial effect of receiving certain nutrients early in life. Future studies on how infant formula should be supplemented to promote health in neonates are also necessary.