● Omega-3 fatty acids have been extensively researched for their immune, cognitive, developmental, visual, skin, and cardiovascular influences. Recent studies have explored the effects of high-dose omega-3s (around 4 g/day) on the intestinal microbiota, but those of more modest supplemental levels are unknown.
● Dietary prebiotics are widely recognized as contributing to intestinal production of gut-nourishing short-chain fatty acids and branched-chain fatty acids (SCFAs and BCFAs) like butyric, iso-butyric, acetic, propionic, valeric, and iso-valeric acids. SCFAs and BCFAs are also known to modulate the immune response, glucose and insulin metabolism, and satiety.
● In this open-label clinical study, 69 adults with low fiber intakes were randomized to receive either 500 mg omega-3 fatty acids (including 165 mg EPA and 110 mg DHA) or 20 g of the prebiotic inulin daily for 6 weeks. Blood and stool samples were collected at baseline and follow-up visits, at which time body mass index (BMI) and body composition were evaluated. Diet and lifestyle behaviors were assessed at baseline, 3 weeks, and follow-up using validated questionnaires. Gut microbial diversity, gut microbiome SCFA and BCFA levels, and blood cholesterol and VLDL levels were analyzed at baseline and follow-up.
Omega-3s as Potential Prebiotics
The results of this clinical study establish omega-3 fatty acids as potential prebiotics that are metabolized by the intestinal microflora to produce short-chain and branched-chain fatty acids, with beneficial effects seen in overweight and lean adults at supplemental omega-3 levels of 500 milligrams daily.