Soy Foods and Cancer Prevention
There is still no solid conclusion whether eating soy foods can prevent breast and prostate cancers, but the research is encouraging, particularly for women
Q: Can soy foods help prevent breast or prostate cancer?
A: The research for the connection between soy food and cancer prevention is promising, particularly for women. Soy foods contain compounds called phytoestrogens, which are similar to very weak forms of estrogen. When taken in from foods instead of supplements, it has subtle anti-cancer effects, but still potentially noteworthy. Phytoestrogens can bind to estrogen receptors in the breasts and other tissue in which it can produce a kinder, gentler substitute for natural estrogen produced by the ovary. Since high lifetime exposure to estrogen is a risk factor for breast cancer, some scientists theorize that phytoestrogens can protect against cancer growth by hindering the natural estrogen and reducing exposure to the hormone. In Asian women, who consume more soy than American women, a diet rich in soy foods has been associated with a lower risk of breast cancer and cancer recurrence. Recent study shows that soy may offer more cancer protection when it’s consumed during childhood and teen years. In men, phytoestrogens also act as subtle estrogens which can balance out testosterone levels. By altering levels of sex hormones, a diet rich in phytoestrogens can help protect against prostate cancer, also another hormone-dependent cancer.
For prostate health benefits, the research is varied. Some studies have shown that men who consume high-soy diets are less likely to develop prostate cancer, while other studies have shown no advantage. I do not recommend men or women to take soy, phytoestrogens, or isoflavones (a class of phytoestrogens) in supplement form, since their effects are not yet fully understood. If you would like to add soy to your diet, skip supplements and highly processed soy foods. Instead try high-quality, whole soy foods such as soybeans (edamame) or tempeh. Warning: If you are being treated for or have a history of breast cancer, consult your doctor before incorporating soy foods into your diet. In many instances, consuming moderate amounts of whole soy foods is perfectly fine, but your doctor may advise you differently based on your personal medical history and treatment plan.