Dietary treatment for familial hypercholesterolemia—differential effects of dietary soy protein according to the apolipoprotein E phenotypes

Familial hypercholesterolemia, one form of type IIa hyperlipidemia, usually responds poorly to standard low-lipid diets. To define the responsiveness to a soy-protein diet in this disease, one homozygous and twenty heterozygous type IIa patients were submitted to a 4-wk traditional hypocholesterolemic diet followed by 4 wk in which animal protein was substituted with texturized soy protein. Soy was then withdrawn for a further 4 wk. No significant changes in plasma lipids were observed during low-lipid diets. The soy diet, however, caused a marked decrease in total (−20.8%) and low-density-lipoprotein (−25.8%) cholesterol and in apoliprotein B (−14.1%). The plasma cholesterol reduction was higher in patients with apoliprotein E 3 /E 3 or E 3 /E 4 vs an almost negligible effect on E 3 /E 2