Consumption of Soy Isoflavones Benefits Postmenopausal Breast Cancer Patients

New research has emerged linking soy isoflavones to reduced recurrence of breast cancer-at least in some women. The results were published in the Canadian Medical Association Journalon Monday.

Researchers at the Cancer Hospital of Harbin Medical University in China conducted food-frequency questionnaires on 542 women who received breast cancer surgery between August 2002 and July 2003. Over an average follow-up of 5.1 years, researchers were looking for any relationship between dietary intake of soy isoflavones and breast cancer recurrence or death.

For premenopausal women, no clear relationships were observed.

Postmenopausal women, however, offered a significant insight. For these women, those who consumed high amounts of soy isoflavones (more than 42 mg daily) were 33% less likely to have breast cancer recurrence compared to subjects who consumed low amounts (less than 15 mg daily).

For women with hormone-positive breast cancer, a 13% decreased risk was observed thanks to high soy isoflavone consumption. Women who were receiving anastrozole therapy (a common breast cancer drug therapy) with high soy isoflavone intake experienced a 19% reduced recurrence compared to low-intake women.

In all patients, soymilk accounted for 26% of soy isoflavone intake, followed by tofu (21%) and soy flour (15%).

To read the full study, click here.