Infant immunity, gut health, may be compromised with fish oil supplementation during breastfeeding

Issue: BCMJ, vol. 62, No. 9, November 2020, Page 344 News

According to researcher Deanna Gibson, an associate professor of biology in the Irving K. Barber Faculty of Science, UBC Okanagan, taking fish oil supplements while nursing may not be beneficial and may even negatively impact babies’ immunity. A study published in the ISME Journal is the first to investigate the impacts of fish oil supplementation on the composition of breast milk and infant gut bacteria.

Researchers demonstrated that supplementation corresponded with an increase in breast milk fats but a decrease in the immune-protective components of the milk, and observed a change in infant gut microbiology—away from the bacteria normally present.

For the study, senior author Gibson and the research team evaluated 91 women and their babies; half took daily doses of fish oil while the other half did not supplement. Breast milk samples, infant stools, and immune function markers were compared between the two groups.

Women who took supplements had a higher ratio of omega-3 fatty acids but lower protective molecules, such as antibodies, in their breast milk. The supplemented infants had a lower diversity of bacteria in their stools, considered a negative. Researchers warn that this is a change that could result in infection risk for the infant. With these findings in mind, Gibson cautions that the practice of prenatal fish oil supplementation may induce long-term dysfunctional gut immunity. Further large-scale studies will clarify whether early fish oil exposures alter infectious disease susceptibility, including persistent asymptomatic chronic infections.

For more information about this study, visit

. Infant immunity, gut health, may be compromised with fish oil supplementation during breastfeeding. BCMJ, Vol. 62, No. 9, November, 2020, Page(s) 344 - News.

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