The study, published in the journal Gut Microbes, found that infant vitamin D supplementation is associated with compositional changes in a baby’s microbiome – notably a lower abundance of the bacteria Megamonas – at three months of age.
The researchers examined fecal samples taken during home visits from 1,157 infants who are part of the CHILD Cohort Study – a national study that is following nearly 3,500 Canadian children from before birth to adolescence with the primary goal of discovering the root causes of allergies, asthma, obesity and other chronic diseases.
They found that direct vitamin D supplementation of infants with vitamin D drops was associated with a lower abundance of Megamonas, regardless of how a baby was fed (breastfed or formula fed). “While little is known about Megamonas in infancy, our previous research suggests there may be a link between this bacterium and asthma or respiratory viral infections, so vitamin D may offer additional benefits for childhood health that should be studied further,” added Dr. Kozyrskyj.
The researchers also assessed the association between infant and maternal vitamin D supplementation and the presence of Clostridioides difficile (C. difficile) in a baby’s gut. “Some infants carry the
diarrhea-causing bacterium C. difficile in their guts without any symptoms. However, when the levels of gut bacteria become imbalanced, this particular bacterium can multiply, causing illness and increasing the susceptibility to chronic disease later in childhood,” commented first author Kelsea Drall, an M.Sc. graduate from the University of Alberta and an AllerGen trainee.
The study found that nearly 30% of the infants carried C. difficile, but a lower incidence of the bacterium was observed among exclusively breastfed infants. However, neither infant supplementation with vitamin D drops nor maternal vitamin D supplementation during pregnancy or after delivery were associated with C. difficile colonization. “Interestingly, maternal consumption of vitamin D-fortified milk was the only factor that reduced the likelihood of C. difficile colonization in infants,” added Ms. Drall.