Effect of omega 3 fatty acids on oxidative stress in humans: GC-MS measurement of urinary F-2-isoprostane excretion

Despite the reported benefits associated with omega 3 fatty acids for cardiovascular disease, there remains concern that increased intake may lead to increased lipid peroxidation. To date, however, the data, particularly in vivo, are inconclusive. This report describes two interventions, one providing daily fish meals and the other eicosapentaenoic acid (EPA, 20:5 omega 3) or docosahexaenoic acid (DHA, 22:6 omega 3), the two principal omega 3 fatty acids in marine oils, in which in vivo lipid peroxidation was assessed by measurement of urinary excretion of F-2-isoprostanes. In both trials, urinary F-2-isoprostanes were significantly reduced by 20-27%. Therefore, in contrast with previous reports in the literature, these results demonstrate that omega 3 fatty acids reduce in vivo oxidant stress in humans.