New study supports cholesterol lowering effect of soy proteinA study conducted by Maki and co-workers shows that soy protein significant lowers total cholesterol and non-high-density lipoprotein cholesterol compared to milk protein in patients with moderately high cholesterol levels.
The researchers explored the effect of the intake of insoluble fraction of soy protein on fasting lipid profile in a randomised, controlled, parallel arm trial. They also investigated the effect on the excretion of bile acids and neutral sterols. The men and women who participated in this study showed fasting LDL-cholesterol concentrations between 100 and 200 mg/dL while receiving no lipid altering therapy. Only those participants who responded to Colesevelam with at least 5% reduction in LDL-cholesterol were selected for the further trials.
The study concluded that soy protein intake has a hypocholesterolemic effect, stronger that that of milk protein. These findings do not support the hypothesis that increased bile acid excretion is an important contributor to the hypocholesterolemic effects of proteins.
Source: Effects of soy protein on lipoprotein lipids and fecal bile acid excretion in men and women with moderate hypercholesterolemia. The Journal of Clinical Lipidology. 2010 Nov-Dec;4(6):531-42.