Dietary fat manipulation has a greater impact on postprandial lipid metabolism than the apolipoprotein E (epsilon) genotype-insights from the SATgenε study

Scope Our aim was to determine the effects of chronic dietary fat manipulation on postprandial lipaemia according to apolipoprotein (APO)E genotype. Methods and results Men (mean age 53 (SD 9) years), prospectively recruited for the APOE genotype (n = 12 E3/E3, n = 11 E3/E4), were assigned to a low fat (LF), high fat, high-saturated fat (HSF), and HSF diet with 3.45 g/day docosahexaenoic acid (HSF-DHA), each for an 8-week period in the same order. At the end of each dietary period, a postprandial assessment was performed using a test meal with a macronutrient profile representative of that dietary intervention. A variable postprandial plasma triacylglycerol (TAG) response according to APOE genotype was evident, with a greater sensitivity to the TAG-lowering effects of DHA in APOE4 carriers (p ≤ 0.005). There was a lack of an independent genotype effect on any of the lipid measures. In the groups combined, dietary fat manipulation had a significant impact on lipids in plasma and Svedberg flotation rate (Sf) 60–400 TAG-rich lipoprotein fraction, with lower responses following the HSF-DHA than HSF intervention (p < 0.05). Conclusion Although a modest impact of APOE genotype was observed on the plasma TAG profile, dietary fat manipulation emerged as a greater modulator of the postprandial lipid response in normolipidaemic men.