Writing in Frontiers in Nutrition, researchers in Malaysia and China found that, compared with placebo, 12 weeks of supplementation with Bifidobacterium infantis YLGB-1496 reduced the incidence of respiratory problems, diarrhea, clinical visits and antibiotic prescriptions in 119 healthy preschool children.
Analysis showed that the probiotic group had reduced inflammatory markers and a trend towards increased fecal IgA, suggesting “a reinforcement of the mucosal barrier, a primary defense mechanism against pathogens,” the researchers wrote. Conversely, the placebo group “displayed an unfavorable trajectory toward dysbiosis.
Furthermore, a significant reduction in salivary cortisol in the probiotic group, “points to a potential systemic effect extending to the gut-brain axis,” they added.
A healthy start
Bifidobacterium infantis YLGB-1496 is a probiotic isolated from breast milk. It has previously been reported to decrease symptoms such as coughs, fever, dry stool and eczema in children.
Globally, infectious diseases such as respiratory disease and diarrhea remain leading causes of death for children under five, according to The World Health Organization, which estimates that the lives over 820,000 children under the age of five could be saved every year if all children 0 to 23 months were optimally breastfed.
Considered the best food for infants, breast milk contains macronutrients, micronutrients and bioactives.
Essential bioactive compounds in breast milk include human milk oligosaccharides (HMOs)—complex sugars that act as prebiotics, feeding beneficial bacteria, such as Bifidobacterium species. HMOs can help regulate the immune system, protect against infections and strengthen the gut barrier.
Based on positive research findings, HMOs have garnered attention in recent years, with more companies investing in this trend and launching various formula milks containing the bioactive ingredient.
“Bifidobacteria, especially in infancy, are known to play a pivotal role in the utilization of HMOs, contributing to energy harvest and the production of short-chain fatty acids (SCFAs) that support gut health,” the current study noted.
Targeted immunomodulatory effect
The researchers suggested that the study results provide compelling evidence that supplementation of B. infantis YLGB-1496 in healthy children “elicits a targeted immunomodulatory effect.”
The probiotic fine-tuned inflammatory pathways rather than exerting a broad immunosuppressive effect, as demonstrated by the stability of TNF-α, IL-6 and IL-4 levels throughout the study and intact Th2-related responses.
“This is a hallmark of a proficient probiotic strain that can enhance defense mechanisms without compromising basal immunity,” the researchers wrote.
“The data for B. infantis YLGB-1496 firmly support its role as an effective nutritional strategy for promoting a balanced immune response and overall resilience in the developing pediatric system.”
Source: Frontiers in Nutrition, 2025, Volume 12, doi: https://doi.org/10.3389/fnut.2025.1713135. “Clinical benefits of Bifidobacterium infantis YLGB-1496 in modulating gut microbiota and immunity in young children.” Authors: M. U. Mageswary, et al.
