Age-Specific Ex Vivo Modulation of Gut–Brain Axis-Associated Metabolites by Galacto-Oligosaccharides and Nutrient Blends in Early Childhood

: Combinations of GOS with nutrient blends impacted microbiome-derived metabolites associated with the gut-brain axis, with potential synergistic increases of metabolites with emerging roles in neurodevelopment, including GABA, acetylagmatine and HICA. Despite shared bifidogenic effects, differences between age groups indicate that microbiome maturity may influence responses to nutritional intervention. Future clinical studies are needed to determine whether these metabolite changes translate into neurodevelopmental benefits in vivo.