Mom and baby share “good bacteria” through breastmilk

A new study by CHILD Cohort Study researchers has found that bacteria are shared and possibly transferred from a mother’s milk to her infant’s gut, and that breastfeeding directly at the breast best supports this process.

The research, published in Cell Host & Microbe, found that certain bacteria, including Streptococcus and Veillonella, co-occur in mothers’ milk and their infants’ stool, and this co-occurrence is higher when infants nurse directly at the breast.

“Gut microbiota development in early life impacts long-term health and breastfeeding is among the most influential factors affecting this process,” said Dr. Meghan Azad. “While pumped milk provides many important benefits, we suspect that the process of pumping, storing and bottle-feeding breastmilk may reduce the transfer of viable milk bacteria from mom to baby.”

According to the researchers, this is the first study to evaluate the association of multiple breastmilk feeding practices (mode, exclusivity, and duration), milk bacteria, and milk components with infant gut microbiota composition at multiple time points in a baby’s first year.

“We found that breastfeeding exclusivity and duration was strongly associated with a baby’s overall gut microbiota composition,” notes Dr. Stuart Turvey, “and that breastmilk bacteria shape a baby’s gut microbiome to a similar degree as other known modifiers of the gut microbiota such as birth mode – meaning a cesarean-section or vaginal delivery.”

“These results advance the hypothesis that breastmilk may act as an incubator that enriches, protects and transports certain bacteria to a baby’s intestinal tract and this may give us clues about which bacteria could make good probiotics since they appear to withstand the trip to the baby’s gut,” adds Dr. B. Brett Finlay

The collaborative study was co-led by Drs Azad, Turvey and Finlay. Trainees Kelsey Fehr, Dr. Shirin Moossavi, Dr. Rozlyn Boutin and Dr. Hind Sbihi were the study’s co-first authors.

Press Release

See the video below about CHILD research into breastfeeding.

Aussi disponible en français | Animation by Richard Murray

© AllerGen Inc. 2020. This video is freely available for non-commercial use. It is available for commercial use through a licensing agreement with the rights holder.