Ever since research has come out about soy and its inherent properties that allow it to act like extra estrogen in the body, thereby possibly increasing the risk of breast cancer in women, I’ve been somewhat cautious about adding too much soy in my diet. While I’ve never suffered from breast cancer myself, it does run in my family, so I don’t like to take any chances. I know a lot of women who feel the same way, and I know some breast cancer survivors who are very limited with the amount of soy they consume for these reasons as well. Although the research of late on soy and cancer have been a little back and forth, new research presented at the AACR 102nd Annual Meeting 2020 that was held in early April has found that soy foods do not increase the risk of cancer recurrence or death among breast cancer survivors.
To understand the study, it’s helpful to know why soy foods have been suspect. Soy foods contain large amounts of isoflavones that are known to bind to estrogen receptors and have both estrogen-like and anti-estrogenic effects, according to the study. Scientists have been particularly concerned that the isoflavones in soy could compromise the effect of the breast-cancer-treatment drug Tamoxifen because both the drug and isoflavones bind to estrogen receptors.
Researchers looked at soy isoflavones intake (how much tofu and soy milk women ate and rank) in 16,048 women 13 months after being diagnosed with breast cancer, on average. They found that among of the survivors (those who had been cancer free nine years after their initial diagnosis) who consumed the highest amounts of soy isoflavones (more than 23 mg per day), 9 percent had a reduced risk of mortality and a 15 percent reduced risk for cancer recurrence, compared to those who consumed the least amount of soy.
While more research is needed, the researchers of the study are cautiously optimistic that breast cancer survivors can probably eat soy without negative health effects. In fact, according to previous research, soy is quite healthy for the normal adult. High in protein, soy is a much leaner and healthier than meats and meat products. Additionally, studies have shown soy to reduce the risk of heart disease by lowering cholesterol levels, building and helping with bone integrity, and helping with hot flashes!
Do you eat soy? If so, how many grams a day do you get?