October 20, 2010
Soy Offers Lower Recurrence Of Breast Cancer
(Ivanhoe Newswire) "“ Big joy for soy! New research finds that high amounts of the wholesome combination of protein, isoflavones and fiber 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 estrogen in chemical structure, and furthermore may stimulate or inhibit estrogen-like action in tissues. Isoflavones "“ such as genistein "“ are believed to in due course have estrogen-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 propos 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 estrogen "“ 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. The authors conclude that while this finding is potentially vital regarding soy intake, large multicentre clinical trials are still needed to provide more data.
SOURCE: Canadian Medical Association Journal, October, 2010