Effects of soy food consumption in preventing hepatocellular carcinoma: A systematic review and meta-analysis.

Abstract

526 Background: Hepatocellular carcinoma (HCC) is a leading cause of cancer-related mortality worldwide. Soy contains isoflavones and other bioactive compounds with anti-inflammatory and anti-proliferative effects that may influence liver carcinogenesis. However, epidemiologic studies have reported inconsistent findings. This review aims to investigate the association between soy food consumption and the risk of HCC. Methods: A systematic search was conducted in PubMed, Scopus, and Cochrane for relevant studies published up to 6 September 2025. We included case-control and cohort studies that reported risk estimates for HCC based on varying levels of soy consumption, and assessed heterogeneity using Cochrane’s Q and I² statistics. Random-effects meta-analysis with inverse-variance method was used to pool effect sizes comparing the highest versus lowest categories of soy food consumption. Results: Three studies involving 22,153 participants, all from Asian populations, were included. Based on two case-control studies, in unadjusted analysis, soy food consumption was associated with 10% reduced odds of HCC (odds ratio [OR] 0.90 [95%CI, 0.83-0.98]; I 2 =0.0%, p=0.69). However, after adjusting for key confounders including hepatitis B or C infection and other lifestyle factors such as alcohol use and smoking, this association was no longer significant (adjusted OR 0.46 [0.13-1.60]; I 2 =97%, p<0.001), consistent with findings from a prospective cohort study. Dose-response analysis was not feasible due to inconsistent measurement units. Conclusions: These findings suggest that soy consumption alone is unlikely to play a major role in HCC prevention. Large-scale prospective studies with standardized dietary assessments are needed to clarify whether soy has benefits in high-risk populations, particularly those with chronic liver disease.