Human milk is not “merely nutritious”: How its bioactive role can influence child health

Maternal milk represents the best food for the newborn, providing specific physiologic advantages over the other sources of nutrition. It also contains many hundreds to thousands of bioactive molecules that protect against infection (i.e. IgA), inflammation (i.e. 5-methylthioadenosine) and contribute to eliciting strong immune responses in breastfed children (i.e. allergens or viral antigens). Quality and quantity of breast milk components may influence the development of infant body composition in the first years of life; in particular, it has been shown that a different composition of human oligosaccharides (HMOs) in overweight/obese women’s human milk can be correlated with her offspring’s growth. This could be associated with human milk’s probiotic role, since probiotics support the assembly of a healthy gut microbiome, by stimulating the growth of beneficial microbes. Therefore, the aim of this review is to outline the bioactive role of human milk and its potential beneficial effect on a child’s long-term health.