Scientists from Xi’an Jiaotong University and several collaborating institutions have found that eating soy foods may help reduce the risk of developing cancer, although it does not appear to affect cancer mortality.
Soybeans and soy-based foods have long been linked to various health benefits, including reduced risks of stroke and coronary heart disease, better bone health, and protection against certain cancers.
Soy is also a major dietary source of isoflavones, plant compounds that may offer protection against age-related diseases such as heart disease, osteoporosis, hormone-dependent cancers, and cognitive decline.
These protective effects may stem from their weak estrogen-like activity and antioxidant properties.
Previous studies examining the relationship between soy consumption and cancer risk have produced mixed results, and it has remained unclear whether any anticancer benefits are due to soy isoflavones, soy protein, or both.
In this study, researchers conducted a comprehensive review of 81 studies published before September 16, 2021, evaluating the associations between soy intake, soy isoflavones, soy protein, and cancer incidence and mortality.
The findings showed that higher soy consumption was strongly associated with a 10% reduction in overall cancer risk. Additionally, for every 25 grams of soy consumed per day, cancer incidence decreased by 4%.
Soy isoflavone intake was also linked to a lower risk of cancer, with each 10 mg/day increase in isoflavone intake associated with a 4% reduction in cancer incidence. In contrast, soy protein intake did not show a clear relationship with cancer risk.
The protective associations were also observed for several specific cancers, particularly lung cancer and prostate cancer. However, high intake of soy, soy isoflavones, or soy protein did not show any significant effect on cancer mortality.
Based on these results, the researchers suggest that higher consumption of soy foods and soy isoflavones is linked to a lower risk of developing cancer. This indicates that the anticancer benefits of soy may be mainly due to soy isoflavones rather than soy protein. The findings support dietary recommendations encouraging the inclusion of soy foods as part of a healthy, balanced diet for cancer prevention.
The study was conducted by Yahui Fan and colleagues and published in Frontiers in Nutrition.
If you care about cancer, please read studies that low-carb diet could increase overall cancer risk, and vitamin D supplements strongly reduces cancer death.
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