Term Infant Formula Supplemented with Human Milk Oligosaccharides (2′Fucosyllactose and Lacto‐N‐neotetraose) Shifts Stool Microbiota and Metabolic Signatures Closer to that of Breastfed Infants

Human milk oligosaccharides (HMOs) may provide benefits to formula‐fed infants in part by influencing the establishment of the intestinal microbiota. We evaluated effects of infant formula with 2 HMOs (2′Fucosyllactose [2′FL] and Lacto‐N‐ neo tetraose [LNnT]) on the early intestinal microbiota in infants (ClinicalTrials.gov NCT01715246). Healthy term infants ages 0–14 days were randomly assigned to intact protein cow's milk‐based infant formula (Control, n 87) or the same formula with 1.0 g/L 2′FL and 0.5 g/L LNnT (Test, n 88); a reference group of breastfed infants was also included ( n 38). Stool samples were collected at age 3 months for assessment of microbiota using 16S rRNA gene sequencing and metagenomics; metabolic signature was assessed using proton NMR‐based metabolite profiling. The global average microbial composition profile, established for infants with available stool samples who had adhered to the study protocol, showed a similar pattern for Control ( n 65) and Test ( n 58) at the genus level, although Test was closer to breastfed ( n 34) than Control. Calculation of microbial alpha diversity and comparison of the global microbiota composition using random permutations of the redundancy analysis (RDA) confirmed that Test was different from Control at the genus level (p<0.001) and closer to the breastfed group. Statistical analyses identified several taxa differentially present in Control and Test: Bifidobacterium (p=0.01), Escherichia (p=0.008), unclassified Coprobacillaceae (p=0.01), unclassified Peptostreptococcaceae (p=0.026), Dorea (p=0.033), and Megamonas (p=0.035). Correction for False Discovery Rate confirmed the first three observations. Main discriminants between Test and Control by random forest analysis were Bifidobacterium , Escherichia and Peptostreptococcaceae . Clinically relevant pathogens were rare; however, Clostridium difficile toxin A/B was detected in 14% of Test and 26% of Control (OR 0.47, CI 0.17–1.27, p=0.15). Multivariate analysis identified phenylalanine, isoleucine, tyrosine, fecal organic acids and fucosylated compounds as influential metabolites that discriminated between the Test, Control and breastfed groups. Globally, the values observed in Test were more similar to those observed in the breastfed group compared with Control, a finding that may indicate reduced protein fermentation. Together these findings indicate that the addition of 2′FL and LNnT to a starter infant formula shifts the stool microbiota and metabolic signature towards those observed in breastfed infants, both in several aspects of composition and function. Further studies are warranted to evaluate whether such a shift in gut ecology towards the breastfed standard leads to health benefits. Support or Funding Information The study was funded by Nestec S.A.