To Soy or Not to Soy

My apologies to Shakespeare for the skewed headline, but that’s the first thing that came to mind when I read the results of a recent report on a perennially confusing topic for those of us who have had breast cancer: whether eating soy products is helpful or harmful.

Some studies show that, because of its estrogen-like properties, soy products should be avoided by people with hormone-positive breast cancer. But there’s evidence from East Asian countries that eating soy might actually be protective, as the rates of breast cancer there are considerably lower than those in the U.S. So which is it?  Is soy helpful? Harmful?

The study came to  my attention in the March email newsletter from the Cancer Prevention Institute of California, whose name tells you exactly what their mission is. Their slogan: Preventing Cancer. Promoting Life.

The newsletter reads:

Eating a soy-rich diet found to reduce mortality for women with more aggressive breast cancers

Consuming more foods rich in isoflavones, a compound primarily found in soy beans, was found to decrease the risk of death of women diagnosed with some types of breast cancer. For all breast cancers combined, mortality was reduced by 21 percent. When considering specific types of breast cancer, lower mortality was found only for women whose tumors lacked estrogen and progesterone receptors. Mortality was 51% lower for women with hormone receptor negative breast cancers which are more aggressive and have poorer survival. Lower mortality was only seen in women who didn’t receive endocrine therapy as a treatment for breast cancer.

To conduct this study, researchers analyzed data on 6,235 American and Canadian breast cancer patients from the Breast Cancer Family Registry, a National Cancer Institute-funded program that has collected clinical and questionnaire data on enrolled participants and their families since 1995.

To their credit, the CPIC took part in the study and one of their researchers collaborated on it. Their report can be found here, with a link to the study published in the journal Cancer.

The study doesn’t entirely solve the riddle of whether soy can help cause or prevent breast cancer for everyone. But for those of us in the triple negative group, it appears eating soybeans can be helpful. The golden words from the summary are: Mortality was 51% lower for women with hormone receptor negative breast cancers.

So break out the edamame. And while you do, listen to a blues singer I just discovered, who puts her soul into this piece for a cancer fundraiser: