Functional Significance of Different Milk Constituents in Modulatingthe Gut Microbiome and Infant Health

Human milk, the gold standard for optimal nourishment, controls the microbial composition of infants by eitherenhancing or limiting bacterial growth. The milk fat globule membrane has gained interest in gut-related functions and cognitivedevelopment. The membrane proteins can directly interact with probiotic bacteria, influencing their survival and adhesion throughgastrointestinal transit, whereas membrane phospholipids increase the residence time of probiotic bacteria in the gut. Thecommensal bacteria in milk act as the initial inoculum in building up the gut colonization of an infant, whereas oligosaccharidespromote proliferation of beneficial microorganisms. Interestingly, milk extracellular vesicles are also involved in influencing themicrobiota composition but are not well-explored. This review highlights the contribution of different milk components inmodulating the infant gut microbiota, particularly the fat globule membrane, and the complex interplay between host-and brain-gut microbiota signaling affecting infant and adult health positively.