Effects of Soy Food and Soy Isoflavone Consumption on Cardiovascular Disease Risk Factors—A Systematic Review and Meta-analysis of Randomized Controlled Trials in Asian Countries

The consumption of whole soy foods and soy isoflavones may exert favourable effects on cardiovascular disease (CVD). However, the effects of soy foods and soy isoflavones on CVD in Asian countries have yet to be systematically investigated. The aim of this systematic review and meta-analysis was to determine the effects of whole soy food and soy isoflavone consumption on CVD risk factors in Asian countries. Electronic databases, including Scopus, PubMed, and Web of Science, were systematically searched from January 2012 to January 2023. A total of 2545 studies were screened and randomized controlled trials (RCTs) exploring the effects of soy on CVD risk factors among adults in Asian countries were included. Meta-analysis was performed using random-effects models, as was subgroup analysis. A total of 17 studies were eligible for inclusion. Our results revealed that soy consumption led to a significant reduction in triglyceride levels (mean difference -13.27, 95% CI -23.70, -2.85)mg/dL, systolic blood pressure (mean difference -6.06, 95% CI -9.80, -2.32) mmHg, diastolic blood pressure (mean difference -4.00, 95% CI -6.03, -1.97) mmHg, and hs-CRP levels (mean difference -0.34, 95% CI -0.63, -0.05) mg/L. In conclusion, our meta-analysis suggests that the consumption of whole soy foods and soy isoflavones has a beneficial effect on triglyceride, blood pressure, and hs-CRP levels. However, there were no favourable effects on other lipid profiles and endothelial function. A further well-conducted RCT with a larger sample size is required to fully understand the combined effects of soy food and soy isoflavone consumption on CVD risk factors.