The overall body of research indicates that soyfoods do not increase the risk of breast cancer or cancer recurrence. Although some in vitro and animal studies suggest that soy isoflavones, but not whole soy foods, might be contraindicated for women at high risk for breast cancer,1 human clinical trials support the safety of soy and soy isoflavone consumption.2 In fact, research indicates that soy consumption during childhood and/or adolescence is associated with a lower risk of breast cancer later in life.3,4 A recent study indicates that soy is not only safe for breast cancer patients, but it may also have a positive impact, potentially helping to decrease the incidence of breast tumor recurrence.5
The American Cancer Society confirms that breast cancer patients can consume soy foods like soymilk, tofu and edamame regularly.6
Katy Raneri is the director of nutrition at WhiteWave Foods. Her responsibilities include establishing an industry-wide center of expertise in health and wellness for the company; developing and implementing Full bio >>
1. Ju YH, Fultz J, Allread KF, Doerge DR, Helferich WG. Dietary genistin stimulates growth of estrogen-dependent breast cancer (MCF-7) tumors implanted in ovariectomized athymic mice. Carcinogenesis. 2006; 27: 856-63.
2. Messina MJ, Wood CE. Soy isoflavones,estrogen therapy, and breast cancer risk: analysis and commentary. Nutr J. 2008 Jun 3;7:17.
3. Korde LA et al. Childhood soy intake and breast cancer risk in Asian American women. Cancer Epidemiol Biomarkers Prev. 2009; Apr 18(4): 1050-9.
4. Shu X et al. Soyfood intake during adolescence and subsequent risk of breast cancer among Chinese women. Cancer Epidemiol Biomarkers Prev 2001; 10:483-8.
5. Xiao OS et al. Soy food intake and breast cancer survival. JAMA. 2009; 302(22):2437-2443.
6. Doyle C et al. Nutrition and physical activity during and after cancer treatment: an American Cancer Society guide for informed choices. CA Cancer J Clin. 2006 Nov-Dec; 56:323-53.