THE EFFECT OF SHORT-TERM FASTING, APOLIPOPROTEIN-E GENE POLYMORPHISM,AND SEX ON PLASMA-LIPIDS

The effect of 1 wk of supervised fasting on plasma lipid concentration s in subjects with different apolipoprotein E (ape E) phenotypes was s tudied in 58 healthy free-living volunteers. The participants consumed an 870-kJ (208 kcal)/d liquid diet containing fruit and berry juices, tea, and water. The decline in plasma total cholesterol during 1 wk o f fasting was 0.46 mmol/L in women and 0.35 mmol/L in men. The decreas es were significant in both women and men. The response patterns of pl asma total cholesterol were not significantly different between the se xes. In men, the changes in plasma low-density-lipoprotein cholesterol during the fast differed significantly (P = 0.0181) between the apo E phenotypes, whereas in women there were no differences due to phenoty pe (P = 0.695). The magnitude of the change in plasma triacylglycerol during the fast was different between the sexes (P = 0.0099). The chan ges in plasma triacylglycerols differed significantly between apo E ph enotype groups in men (P = 0.0295) but not in women (P = 0.0661). Stat istical comparison between different apo E phenotypes was performed wi th and without the small apo E3,2+E2,2 group, with essentially similar results. During fasting, plasma high-density-lipoprotein cholesterol concentrations decreased slightly but not significantly. The study sho ws significant differences in the associations of apo E alleles and se x on plasma lipid responses during fasting and illustrates the importa nce of gene-diet interactions in the regulation of lipid metabolism in humans.