Soy Flour Muffins Do Not Improve Risk Factors for Cardiovascular Disease in Adults with Hypercholesterolemia

Abstract

Soy may reduce cardiovascular disease (CVD) risk by lowering LDL cholesterol (LDL‐C), but it is not known whether this health benefit is related to the matrix of soy foods. This study assessed the dose‐dependent LDL‐C lowering effect of muffins made with whole de‐fatted soy flour in addition to other CVD risk factors. In a double‐blind, parallel, multicentre clinical trial, healthy adults (n = 243) with elevated LDL‐C (蠅 3.0 and 蠄 5.0 mmol/L) were randomly assigned to consume daily for 6 weeks either: (1) two soy muffins (25g soy protein); (2) one soy and one wheat muffin (12.5g soy protein and 12.5g whey protein); or (3) two wheat muffins (25g whey protein, control). A one‐way ANOVA determined the effect of treatment on the net change in fasting plasma lipids, C‐reactive protein (CRP), glucose, insulin, insulin resistance (HOMA‐IR), and blood pressure. Analyses were performed by intention‐to‐treat. Participants had a mean (±SD) age of 55.0±8.8 years and were overweight (BMI: 28.0±4.6 kg/m2). No significant net change in LDL‐C was found in the groups assigned to soy compared to control (0.01±0.05 mmol/L vs. ‐0.04±0.05 mmol/L vs. ‐0.04±0.05 mmol/L; p = 0.718). Further, there were no significant intervention effects on other CVD risk factors. Whole de‐fatted soy flour muffins do not lower LDL‐C and other CVD risk factors in hypercholesterolemic adults. Funded by the Government of Canada Growing Forward I Science Substantiation Program (RBPI#1746).