Science

Janie Allaire, Patrick Couture, Myriam Leclerc, Amélie Charest, Johanne Marin, Marie-Claude Lépine, Denis Talbot, André Tchernof, and Benoit Lamarche

Background:
To date, most studies on the anti-inflammatory effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in humans have used a mixture of the 2 fatty acids in various forms and proportions.
Objectives:
We compared the effects of EPA supplementation with those of DHA supplementation (re-esterified triacylglycerol; 90% pure) on inflammation markers (primary outcome) and blood lipids (secondary outcome) in men and women at risk of cardio- vascular disease.
Design:
In a double-blind, randomized, crossover, controlled study, healthy men (n = 48) and women (n = 106) with abdominal obesity and low-grade systemic inflammation consumed 3 g/d of the following supplements for periods of 10 wk: 1) EPA (2.7 g/d), 2) DHA (2.7 g/d), and 3) corn oil as a control with each supplementation sep- arated by a 9-wk washout period. Primary analyses assessed the difference in cardiometabolic outcomes between EPA and DHA.
Results:
Supplementation with DHA compared with supplementation with EPA led to a greater reduction in interleukin-18 (IL-18) (27.0% 6 2.8% compared with 20.5% 6 3.0%, respectively; P = 0.01) and a greater increase in adiponectin (3.1% 6 1.6% compared with 21.2% 6 1.7%, respectively; P , 0.001). Between DHA and EPA, changes in CRP (27.9% 6 5.0% compared with 21.8% 6 6.5%, respectively; P = 0.25), IL-6 (212.0% 6 7.0% compared with 213.4% 6 7.0%, respectively; P = 0.86), and tumor necrosis factor-a (214.8% 6 5.1% compared with 27.6% 6 10.2%, respectively; P = 0.63) were NS. DHA compared with EPA led to more pronounced reductions in triglycerides (213.3% 6 2.3% compared with 211.9% 6 2.2%, respectively; P = 0.005) and the cholesterol:HDL-cholesterol ratio (22.5% 6 1.3% compared with 0.3% 6 1.1%, respectively; P = 0.006) and greater increases in HDL cholesterol (7.6% 6 1.4% compared with 20.7% 6 1.1%, respectively; P , 0.0001) and LDL cholesterol (6.9% 6 1.8% compared with 2.2% 6 1.6%, respectively; P = 0.04). The increase in LDL-cholesterol concentrations for DHA compared with EPA was significant in men but not in women (P-treatment 3 sex interaction = 0.046).
Conclusions:
DHA is more effective than EPA in modulating specific markers of inflammation as well as blood lipids. Additional studies are needed to determine the effect of a long-term DHA supplementation per se on cardiovascular disease risk.