Long-Term Associations of Early-Life Human Milk Oligosaccharide Intake with Allergic Disease Development and Gut Microbiota Profiles in 5-Year-Old Children.

Higher HMO intake levels across five distinct lactation periods may be linked to a reduced incidence of allergies in children at age 5.

• Data were drawn from the Maternal Nutrition and Infant Investigation (MUAI) cohort study.
• Human breast milk samples were collected at five lactation stages.
• Children aged 5 years were categorized into allergic and non-allergic groups via standardized allergen testing.
• The association was observed across multiple lactation periods, suggesting a cumulative or sustained early-life effect.

Consumption of six major structurally representative HMOs was significantly associated with alterations in gut microbiota profiles of young children.

• Six HMOs were identified as structurally representative and analyzed for their associations with microbiota.
• Fecal samples of infants and young children were collected to assess gut microbiome composition.
• The associations were observed between specific HMO intake levels and changes in microbiota profiles.
• The findings link early dietary HMO exposure to measurable differences in gut microbial communities.

Notable differences in gut microbiota composition were found between allergic and non-allergic 5-year-old children.

• Beneficial bacteria including Bifidobacterium, Akkermansia, and Ruminococcus were significantly enriched in the non-allergic group.
• Levels of propionic acid, described as a beneficial short-chain fatty acid (SCFA), were notably higher in the non-allergic group.
• The differences in microbiota were identified through fecal sample analysis at age 5.
• These differences suggest a potential microbiota-mediated mechanism linking early HMO intake to allergic outcomes.

Bifidobacterium adolescentis was identified as a differential strain biomarker showing significant correlations with specific HMOs at different lactation stages.

• B. adolescentis was identified through analysis aimed at validating the relationship between Bifidobacterium abundance and early HMO intake.
• B. adolescentis exhibited a strong positive correlation with 2'-fucosyllactose (2'-FL) content specifically.
• The correlations were observed across different lactation stages, suggesting stage-specific HMO-microbiota interactions.
• This finding further supports the mechanistic link between early 2'-FL intake and beneficial microbiota enrichment.