New research published in the Journal of Nutrition, by David Jenkins, MD, PhD and colleagues from the University of Toronto, shows that soy protein significantly lowers LDL-cholesterol, the type of cholesterol known to raise risk of heart disease. While previous research has found similar results, in recent years challenges to the cholesterol-lowering effect of soy protein have been raised. In fact, in October 2017, the U.S. Food and Drug Administration (FDA) announced its intention to revoke the existing health claim for soy protein and coronary heart disease, which was approved in 1999, citing inconsistent data.
The research by Jenkins is a meta-analysis of previously published data, the same data upon which the FDA based its decision. Of the 46 studies identified by the FDA, 41 studies involving 3,228 participants were suitable for inclusion in the analysis for the evaluation of LDL-cholesterol and 43 studies involving 3,290 participants were suitable for the evaluation of total cholesterol. Soy protein lowered LDL-cholesterol 3.2%. Although modest, over time, each 1% reduction in LDL-cholesterol is thought to reduce the risk of heart disease by 1 to 2%.