University of Alberta: Vitamin D Is Beneficial for the Microbiota of Newborns

A study involving over 1,100 babies suggests that vitamin D supplementation can have a positive effect on intestinal microbiota by preventing the multiplication of certain bacteria.

Vitamin D

Prescribed from birth to 18 months of age as a supplement to breastfeeding or formula milk, vitamin D plays an essential role in maintaining bone mass and the healthy development of the baby’s immune system.

According to a new Canadian study published in Gut Microbes magazine, vitamin D also has a positive effect on the composition of the baby’s intestinal microbiota, particularly as it is associated with a lower incidence of Megamonas bacteria at three months of age. “Most babies in North America receive vitamin D, either as a supplement to breastfeeding or as an ingredient in commercial baby formulas. That’s why we wanted to understand the relationship between vitamin D and the presence or incidence of key bacteria in a baby’s intestinal tract,” says Anita Kozyrskyj, professor at the Department of Pediatrics at the University of Alberta, Canada, and lead author of the article.

A protective effect

To investigate the association between vitamin D supplementation and newborn microbiota, researchers examined fecal samples collected from 1,157 babies in the CHILD cohort during home visits.

They found that direct supplementation of infants with vitamin D drops was associated with a lower incidence of megamonas, regardless of how the infant was fed (breastfeeding or formula). “Although little is known about megamonas in infants, our previous research suggests that there may be a link between this bacterium and asthma and viral respiratory infections, so vitamin D can offer an additional benefit to children’s health,” says Dr. Kozyrskyj.

Researchers have also investigated the association between vitamin D supplementation in infants and mothers and the presence of Clostridioides difficile (C. difficile) in a baby’s intestine. “Some babies carry the C. difficile bacteria causing diarrhea in their intestines without symptoms. However, when intestinal bacteria are unbalanced, these particular bacteria can multiply, leading to disease and increasing susceptibility to chronic disease in late childhood,” said Kelsea Drall, who participated in the study.

Although research has shown that almost 30% of babies carry C. difficile, researchers also found that the incidence of the bacteria was lower in babies who were exclusively breastfed. In addition, neither the baby’s supplementation with vitamin D drops nor the maternal supplementation with vitamin D during pregnancy or after delivery was associated with colonization of C. difficile. “It is interesting to note that maternal consumption of milk enriched with vitamin D was the only factor that reduced the likelihood of colonization of C. difficile in babies,” adds Kelsea Drall.

An immature microbiota

According to researchers, a child’s intestinal microbiota is subject to rapid changes in early life, especially during the first three months of life. It is therefore crucial to understand the factors associated with the microbial communities that populate a child’s intestine in this important phase of development.

“Low levels of vitamin D have been associated with Syncytial Respiratory Virus (RSV) – a common lung infection in infants – and more recently with susceptibility to COVID-19,” says Anita Kozyrskyj. In the study of the infant cohort, we have the unique opportunity to accompany children in our study as they grow to understand how microbial changes observed as a result of nutritional interventions can be linked to subsequent health outcomes such as asthma and viral infections”.