Genistein and Other Soy Isoflavones Reduce Breast Cancer Reoccurrence

Thursday, 21/10/2010  |   Breast Cancer, Herb or Compound, Slider  |  2 comments

New research finds that high amounts of the wholesome combination of protein, isoflavones and fibre that make up soy lower the risk of cancer recurrence in post-menopausal breast cancer patients with hormone-sensitive cancers. Soy has already been investigated for benefit in terms of cardiovascular disease, weight loss, arthritis, brain function, as well as exercise performance enhancement.
Soy isoflavones are comparable to oestrogen in chemical structure, and furthermore may stimulate or inhibit oestrogen-like action in tissues. Isoflavones – such as genistein — are believed to in due course have oestrogen-like effects in the body, and as a result are sometimes called “phytoestrogens.” Researchers at the Harbin Medical University in Harbin, China studied 524 women who had surgery for breast cancer, in which they were followed afterwards for between five to six years. With little data a apropos the effects of soy isoflavones on breast cancer patients receiving adjuvant endocrine therapy, the researchers sought to understand its impact in these patients.
“Compared with postmenopausal patients in the lowest quartile of soy isoflavone intake (less than 15.2 mg/day), those in the highest quartile (more than 42.3 mg/day) had a significantly lower risk of recurrence,” which Dr. Qingyan Zhang was quoted as saying. “The recurrence rate of oestrogen — and progesterone — positive breast cancer was 12.9% lower among patients in the highest quartile of soy isoflavone intake than among those in the lowest quartile and was 18.7% lower for patients receiving anastrozole therapy in the highest quartile.”
Conversely, there was no general effect on survival in postmenopausal women in addition to no association between soy intake and survival in premenopausal women.
In this study, high dietary intake of soy isoflavones was associated with reduced risk of recurrence of disease among postmenopausal patients with oestrogen- and progesterone-receptor positive breast cancer and those who were receiving anastrozole as endocrine therapy. This finding is potentially important in terms of recommendations for intake of soy isoflavones in conjunction with endocrine therapy.
Kang, X-M., Zhang, Q-Y., Wang, S-H., Huang, X. & Jin, S. Effect of soy isoflavones on breast cancer recurrence and death for patients receiving adjuvant endocrine therapy. Canadian Medical Association Journal, October 18, 2010 DOI: 10.1503/cmaj.091298


  1. Christina Zabolitzki
    Nov 13, 2010

    Does this article mean that it is ok for me to take Citrical (Ca + Vit. D + Genistein) in addition to Arimidex. I am a 8-year BC survivor of hormone sensitive BC?

    • chris hannah
      Feb 25, 2013

      I would talk to your oncologist before i would -b.c. 10yr survivor

Leave a Reply

You must be logged in to post a comment.