Omega‐3 fatty acid concentrates dose‐dependently alter triglycerides and erythrocyte fatty acid composition with no effect on in endothelial function

Abstract

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) reduce cardiovascular mortality. However, there is inconsistent evidence about whether omega‐3 fatty acids (FAs) improve inflammation & endothelial function. Furthermore, the doses used in past studies were much higher than recommended intakes. We compared the effects of 0.85 g and 3.4 g of EPA + DHA provided as 1 g and 4 g omega‐3 acid ethyl esters (O3AEE, Lovaza™) in 28 people with moderate hypertriglyceridemia (150–500 mg/dL) in a placebo‐controlled, double‐blind, randomized, crossover trial (8 wk treatments, 6 wk washout). The 4 g dose reduced triglycerides (TGs) by 27% vs. placebo (p = 0.002), whereas the 1 g dose had no effect. Erythrocyte FA composition changed in a dose‐dependent manner for many FAs including arachidonic acid, EPA, DHA, and linoleic acid (each p < 0.0001). The omega‐3 index (EPA+DHA in erythrocytes) increased from 4.4% after placebo to 6.5% and 8.8% with the 1 g and 4 g doses, respectively. However, there were no changes in endothelial function as assessed by flow‐mediated dilation or peripheral arterial tonometry, or in inflammatory markers (IL‐1β, IL‐6, TNF‐α, hs‐CRP). This work confirms the efficacy of O3AEE in lowering TGs, although the higher dose is required to achieve this effect. This study was supported by GlaxoSmithKline and the National Fisheries Institute.