Effect of omega-3 fatty acids supplementation on endothelial function: A meta-analysis of randomized controlled trials

ObjectiveInverse association was reported between omega-3 fatty acids (FAs) supplementation and the risk of cardiovascular disease. Identifying the effect of omega-3 FAs on endothelial function may contribute to explain the association. We conducted a meta-analysis to assess the effect of omega-3 FAs supplementation on endothelial function, as measured by flow-mediated dilation (FMD) and endothelium-independent vasodilation (EIV).MethodsRandomized placebo-controlled trials (RCTs) were identified from the databases of PubMed, EMBASE and Cochrane library by two investigators and the pooled effects were measured by weighted mean difference (WMD), together with 95% confidence intervals (CIs). Subgroup and meta-regression analyses were used to explore the source of between-study heterogeneity.ResultsTotally 16 eligible studies involving 901 participants were finally included in meta-analysis. Compared with placebo, omega-3 FAs supplementation significantly increased FMD by 2.30% (95% CI: 0.89-3.72%, P = 0.001), at a dose ranging from 0.45 to 4.5 g/d over a median of 56 days. Subgroup analyses suggested that the effect of omega-3 FAs on FMD might be modified by the health status of the participants or the dose of supplementation. Sensitivity analyses indicated that the protective effect of omega-3 on endothelial function was robust. No significant change in EIV was observed after omega-3 FAs supplementation (WMD: 0.57%; 95% CI: −0.88 to 2.01%; P = 0.442).ConclusionSupplementation of omega-3 fatty acids significantly improves the endothelial function without affecting endothelium-independent dilation.

► We examine the effect of omega-3 FAs on endothelial function by a meta-analysis. ► Flow-mediated dilation was significantly improved by omega-3 FAs supplementation. ► No significant effect on endothelium-independent vasodilation was observed.