Fish oil pills, rich in omega-3 polyunsaturated fatty acids, are one of the world’s most popular dietary supplements, said to be useful for pregnant and breastfeeding women to promote infant development.
However, Dr. Deanna Gibson and her team at the University of British Columbia have found that this may not be the case. By looking at the effect that fish oil supplementation had on the gut microbiology of infants, they found that fish oil pills taken by mothers during breastfeeding can compromise the immunity of infants.
In this study, they found that the use of fish oil supplements by mothers led to a decrease in an immune factor found in breastmilk that protects babies from infection, called secretory immunoglobulin A (sIgA). Women who took supplements had a higher ratio of omega-3 fatty acids, but lower protective molecules, such as antibodies in their breast milk as well as high anti-inflammatory cytokines. These led to lower diversity of the infant’s gut bacteria and a change in the order of which bacteria colonize. Overall, they found that defensive inflammation and colonization resistance were impaired—reducing the protection against infectious disease in the infant.
The results of this study caution the use of prenatal fish oil supplements, as they may cause long-term dysfunctional gut immunity. Mothers—either pregnant or breastfeeding—should caution their use of fish oil supplements until more studies are performed to understand its link to infectious disease. “We know that the gut microbiome is intricately linked to infant health,” Dr. Gibson says. “Further large-scale studies will clarify whether early fish oil exposures alter infectious disease susceptibility, including persistent asymptomatic chronic infections.” This study was published in the
ISME Journal: Multidisciplinary Journal of Microbial Ecology.
Dr. Deanna Gibson is a researcher and Associate Professor of Biology at the University of British Columbia, where she studies how the gut microbiome develops in response to environmental factors like diet and how this drives immunity. Dr. Gibson has discovered through her research that specific types of fats, omega-6s—which Western diets are notoriously high in—contribute to inflammation in the gut and cause flares. In contrast, the Mediterranean diet, while also high in fat, is high in monounsaturated fats which support protective inflammation, and do not contribute to flares. Crohn’s and Colitis Canada is supporting Dr. Deanna Gibson and her team’s research into the Mediterranean diet for people with ulcerative colitis.
You can learn more about Dr. Deanna Gibson’s Crohn’s and Colitis Canada supported research at one of our latest Gutsy Learning Series events: Dietary Therapies: The Role of Fat in IBD.
Learn more here.