Omega-3 fatty acids improve postprandial lipemia and associated endothelial dysfunction in healthy individuals – a randomized cross-over trial

BackgroundPostprandial elevation of triglycerides impairs endothelial function and contributes to the development of atherosclerosis. We investigated the effects of omega-3 fatty acids on postprandial endothelial function and lipid profiles.MethodsHealthy volunteers [10] were given supplementation at 4 g/day omega-3 fatty acids (or were not treated) for 4 weeks in a randomised crossover study. Postprandial levels of various lipids were monitored and endothelial function assessed by brachial artery flow-mediated dilation during fasting and after a standard cookie test.ResultsOmega-3 fatty acids reduced postprandial endothelial dysfunction compared with the control diet (flow-mediated dilation at 4 h = −0.5 ± 1.2 vs. −2.0 ± 1.6%, P = 0.03). Postprandial levels of triglycerides, apolipoprotein B-48, and remnant lipoprotein-cholesterol increased in untreated subjects, peaked at 2–4 h, and returned to baseline at 8 h, whereas low-density lipoprotein-cholesterol levels did not change. Supplementation with omega-3 fatty acids significantly suppressed postprandial elevation of triglycerides (incremental area under the curve = 220 ± 209 vs. 374 ± 216 mg/h/dL, P = 0.04) and remnant lipoprotein-cholesterol (incremental area under the curve = 21.7 ± 13.8 vs. 13.3 ± 12.9 mg/h/dL, P = 0.04). Supplementation with omega-3 fatty acids significantly suppressed the increase in triglyceride content in chylomicrons as well as in very-low-density lipoproteins from baseline to 4 h after the cookie test.ConclusionOmega-3 fatty acids significantly decreased postprandial triglyceride elevation and postprandial endothelial dysfunction, suggesting that omega-3 fatty acids may have vascular protective effects in postprandial state.