The Effects of Omega-3 PUFAs on the Infant Microbiome and Immunity

Prenatal supplementation with fish oil, rich in omega-3 polyunsaturated fatty acids, is widely recommended in Canada. The aim of this observational, prospective cohort study is to determine the effects of maternal fish oil supplements on the development of their infants' gut microbiota and immunity.

During infancy, the gastrointestinal tract is colonized with microbiota, a community of microorganisms, which play a significant role in the development, regulation, and maintenance of immune functions. Fish oil, rich in n-3 polyunsaturated fatty acids (PUFA), are thought to be anti-inflammatory and consequently may increase susceptibility to infection by hindering their body's ability to produce an adequate inflammatory response in defense against infectious disease. Currently, women in Canada are supplementing their diets with n-3 PUFA during gestation and lactation despite their being conflicting clinical evidence regarding the beneficial effects on infant development. It is currently unknown how maternal fish oil supplementation impacts the offspring's gut microbiota and immune functions. Considering that diet influences microbiota and maternal microbiota is passed from mother to infant, the investigators hypothesize that maternal fish oil supplementation will affect the participants' infant gut microbiota and immunity. This study will evaluate the effects of postnatal n-3 PUFA supplementation in breast milk on the fecal microbiome in infants over a six-month period. The investigators will analyze the fecal microbiome of infants born to mothers in the fish oil and non-fish oil groups via next generation sequencing. As short-chain fatty acids (SCFA) are produced by gut bacteria and affect immunity, the investigators will analyze SCFA in stool through gas chromatography. Markers of inflammation like fecal calprotectin and sIgA in stool samples will also be identified.