Comparing early life nutritional sources and human milk feeding practices: personalized and dynamic nutrition supports infant gut microbiome development and immune system maturation

Abstract

Exclusive breastfeeding is recommended for the first six months of life, but many infants receive pumped milk, formula, donor human milk, or other nutritional sources during this critical period. Substantive evidence shows early nutrition influences development of the microbiome and immune system, affecting lifelong health. However, the underlying mechanisms are unclear and the nuances of human milk feeding are rarely considered. This review synthesizes evidence from human studies and model systems to discuss the impact of different nutritional sources on co-development of the gut microbiome, antigen tolerance, and immunity. We highlight two key mechanisms: epigenetics and the so-called “weaning reaction”. Collectively, this evidence highlights i) the fundamental role of parents’ own milk, fed directly at the breast, as a dynamic and personalized nutrition source that drives developmental programming, and ii) the deficiencies of alternative nutritional sources and priority research areas for improving these alternatives when direct breastfeeding is not possible.

Infant Formula Supplemented with Five Human Milk Oligosaccharides Shifts the Fecal Microbiome of Formula-Fed Infants Closer to That of Breastfed Infants

“…In the absence of such data, we can only speculate that the higher relative abundance of ALDH + Bifidobacterium and increased metabolic capability for tyrosine degradation lead to higher amounts of aromatic lactic acids. In addition to these results, previous studies have shown that HMO supplements change other infant fecal metabolites, such as the short-chain fatty acid profile, which is attributed to the preferential growth of Bacteroides and Bifidobacterium at the expense of proteobacteria [ 50 , 51 ].…”

Reversible aberrancies in gut microbiome of moderate and late preterm infants: results from a randomized, controlled trial

“… 10 , 12 , 30–33 It is well established that breastfeeding promotes a favorable gut microbiome structure and especially higher levels of Bifidobacterium species. 7 , 13 , 34 In this study, all but one of the preterm infants were breastfed at the age of one month and the mean total duration of breastfeeding in these infants was 4.4 months. This might explain the observed progression of the preterm gut microbiome toward a Bifidobacterium -dominated composition occurring already at 6 months of age.…”

Quantification of Female Chimeric Cells in the Tonsils of Male Children and Their Determinants

“…Our exploratory analyses also found that being previously breastfed was associated with a gentle attrition of microchimeric cells with age, as compared to those that had never been breastfed. Given the relationship between breastfeeding and immune maturation [ 36 , 37 ], this observation suggests tolerogenic properties of microchimeric cells, such as for regulatory T-cells transferred from breastmilk [ 11 ], possibly resulting in enhanced future immune response and improved child health and development.…”