Supplementing breastfed infants with activated Bifidobacterium infantis (B. infantis) bacteria had a positive impact on babies' gut microbes for up to a year, according to a recent study by researchers at the University of California, Davis and Evolve BioSystems Inc. The work will be presented June 9 at the annual meeting of the American Society for Nutrition in Boston by Bethany Henrick, director of immunology and diagnostics at Evolve BioSystems, on behalf of the study co-investigator, Jennifer Smilowitz, associate director of human studies research at UC Davis' Foods For Health Institute.

The presence of B. infantis in the intestines of infants is associated with health benefits and these bacteria are nourished by breast milk. However, these beneficial bacteria are present at significantly lower levels in breastfed infants in developed countries than in developing countries.

Mothers and infants in the study received either a B. infantis preparation and lactation support, or lactation support alone, from seven to 21 days after birth. The bacteria quickly established themselves in the babies, crowding out other gut bacteria that are associated with intestinal problems and immune-related diseases such as asthma, allergy and autoimmune disease. Furthermore, supplementation with B. infantis also changed the biochemical composition of infant feces. These beneficial changes lasted for up to a year in babies that were primarily breastfed.

These results suggest a possible method to improve gut microbiome health and prevent immune-related diseases in breastfed infants in developed countries.