Purified eicosapentaenoic and docosahexaenoic acids have differential effects on serum lipids and lipoproteins, LDL particle size, glucose, and insulin in mildly hyperlipidemic men

Background: Regular consumption of n-3 fatty acids of marine origin can imp rove serum lipids and reduce cardiovascular risk. Objective: This study aimed to determine whether eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids have differential effects on serum lipids and lipoproteins, glucose, and insulin in humans. Design: In a double-blind, placebo-controlled trial of parallel design, 59 overweight, nonsmoking, mildly hyperlipidemic men were randomly assigned to receive 4 g purified EPA, DHA, or olive oil (placebo) daily while continui ng their usual diets for 6 wk. Results: Fifty-six men aged 48.8 +/- 1.1 y completed the study. Relative to those in the olive oil group, triacylglycerols fell by 0.45 +/- 0.15 mmol/ L (approximate to 20%; P = 0.003) in the DHA group and by 0.37 +/- 0.14 mmo l/L (approximate to 18%; P = 0.012) in the EPA group. Neither EPA nor DHA h ad any effect on total cholesterol. LDL, HDL, and HDL, cholesterol were not affected significantly by ERA, but HDL, cholesterol decreased significantl y (6.7%; P = 0.032). Although HDL cholesterol was not significantly increas ed by DHA (3.1%), HDL2 cholesterol increased by approximate to 29% (P = 0.0 04). DHA increased LDL cholesterol by 8% (P = 0.019). Adjusted LDL particle size increased by 0.25 +/- 0.08 nm (P = 0.002) with DHA but not with ERA. EPA supplementation increased plasma and platelet phospholipid EPA but redu ced DHA. DHA supplementation increased DHA and EPA in plasma and platelet p hospholipids. Both EPA and DHA increased fasting insulin significantly. EPA , but not DHA, tended to increase fasting glucose, but not significantly so . Conclusions: EPA and DHA had differential effects on lipids, fatty acids, a nd glucose metabolism in overweight men with mild hyperlipidemia.