The Probable Impact of Soy Isoflavones in Bone Fracture Downturn: A Systematic Review

Background: There is a direct relationship between taking soy isoflavones and higher bone density, but there is a paucity of studies examining the relationship between flavonoid consumption and fracture risk. This study aimed to assess the bone fracture and its relationship to soy product intake by performing a systematic review. Methods: Scopus, PubMed, and Web of science were searched to find studies on the effect of soy isoflavones on bone fracture, without any time and language of publication restrictions. Key words of SoyMilk, soymilk, soybeans, soybean, soy, soya, Isoflavones, Isoflavone, ipriflavone, equol, genistein, daidzein, glycitin, fractures, and broken bone were used. Results: From a total of 1675 articles, 27 studies (cross-sectional studies (n=1), case-control studies (n=1), cohort (n=11), and randomized control trials (n=14)) were identified, and their quality was assessed. Eighteen studies highlighted mainly positive results in preventive influence of soy bone fractures. Two papers reported a positive effect was observed in men with cancer. No significant association was found between soy intake and bone prevention fracture in eight distinct papers. Conclusion: Intake of soy isoflavones can make a significant preventive effect on bone fracture; however, the results of some studies are controversial.  Therefore, it is necessary to survey more studies to identify the relationship between isoflavones and bone fracture.