Effect of fermented soybean on metabolic outcomes, anthropometric indices, and body composition: a systematic review and meta-analysis of clinical trials.

The aim of the current study was to systematically review and quantify the findings of randomized controlled trials (RCTs) assessing the effect of fermented soy products on anthropometric indices, body composition, and metabolic outcomes. PubMed, Scopus, and Web of Science were searched to identify the relevant articles from inception until March 2024. The weighted mean differences (WMD) and corresponding 95% confidence intervals (CI) were calculated as effect sizes and analyzed using the random-effects method. A total of 2205 records were found, of which 15 RCTs were eligible. Results demonstrated significant beneficial effects of fermented soy on body mass index (WMD = -0.14 kg m ^-2 , 95% CI: -0.28, -0.01, P = 0.039), waist circumference (WMD = -1.50 cm, 95% CI: -2.94, -0.07, P = 0.04), visceral fat (WMD = -692.17 mm ² , 95% CI: -1011.58, -372.77, P < 0.001), fasting plasma glucose (WMD = -6.39 mg dL ^-1 , 95% CI: -10.38, -2.40, P = 0.002), and total cholesterol (WMD = -5.0 mg dL ^-1 , 95% CI: -6.60, -3.39, P < 0.001) compared with controls. However, the responses of other parameters to fermented soy were not significant. Overall, fermented soy may confer health benefits on certain metabolic outcomes, anthropometric indices, and body composition.