Docosahexaenoic acid supplementation alters plasma phospholipid fatty acid composition in hyperlipidemic children: Results from the Endothelial Assessment of Risk from Lipids in Youth (EARLY) study

Evidence suggests that dietary n-3 fatty acids, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) are protective against cardiovascular disease. Previous research has shown that DHA supplementation improves vascular endothelial function in hyperlipidemic children. The purpose of this study was to determine the effects of dietary supplementation with DHA on plasma phospholipid fatty acid composition in hyperlipidemic children as a potential mechanism for the vascular response. In a double-blind, placebo-controlled, randomized, cross-over study design, 20 children (9-19 years of age) were counseled to follow the National Cholesterol Education Program Step II (NCEP-II) diet for 6 months. After 6 weeks on diet alone, they were randomly assigned to DHA supplementation (1.2 g/day) or placebo for 6 weeks, followed by a washout phase (6 weeks) and cross-over phase (6 weeks) while continuing the NCEP-II diet. DHA supplementation significantly altered the plasma phospholipid fatty acid profile by increasing DHA concentrations by 250% and decreasing n-6 fatty acid concentrations (20:3n-6, 20:4n-6, 22:4n-6, 22:5n-6). These findings indicate that short-term consumption of DHA is reflected in marked changes in plasma phospholipid fatty acid composition in hyperlipidemic children. This favorable shift in n-3 lipid profile may confer preventive cardiovascular benefits in this young population at high risk for early coronary heart disease. Subsequent incorporation of n-3 fatty acids in vascular tissue may contribute to the restoration of endothelial function associated with DHA supplementation, as previously reported.