EFFECTS OF HIGHLY PURIFIED EICOSAPENTAENOIC ACID AND DOCOSAHEXAENOIC ACID ON FATTY-ACID ABSORPTION, INCORPORATION INTO SERUM PHOSPHOLIPIDS AND POSTPRANDIAL TRIGLYCERIDEMIA

Fourteen healthy volunteers were randomly allocated to receive 4 g hig hly purified ethyl esters of eicosapentaenoic acid (EPA) (95% pure, n = 7) or docosahexaenoicacid (DHA) (90% pure, n = 7) daily for 5 wk in supplement to their ordinary diet. The n-3 fatty acids were given with a standard high-fat meal at the beginning and the end of the suppleme ntation period. EPA and DHA induced a similar incorporation into chylo microns which peaked 6 h after the meal. The relative uptake of EPA an d DHA from the meal was >90% compared with the uptake of oleic acid. D uring absorption, there was no significant elongation or retroconversi on of EPA or DHA in total chylomicron fatty acids. The concentration o f EPA decreased by 13% and DHA by 62% (P < 0.001) between 6 and 8 h af ter the meal. During the 5-wk supplementation period, EPA showed a mor e rapid and comprehensive increase in serum phospholipids than did DHA . DHA was retroconverted to EPA, whereas EPA was elongated to docosape ntaenoic acid (DPA). The postprandial triglyceridemia was suppressed b y 19 and 49% after prolonged intake of EPA and DHA, respectively, indi cating that prolonged intake of DHA is equivalent to or even more effi cient than that of EPA in lowering postprandial triglyceridemia. This study indicates that there are metabolic differences between EPA and D HA which may have implications for the use of n-3 fatty acids in preve ntive and clinical medicine.