Scientific Advisory Board
- Alan Rogol, MD, PhD»
- Ian Rowland, PhD»
- Donna Kritz-Silverstein, PhD»
- Mark Messina, PhD, MS»
- Mary Hardy, MD»
- David Jenkins, MD, DSc, PhD»
Silk®s Nutrition Team
Answered Questions
- Are fermented soyfoods nutritionally superior to unfermented soyfoods?»
- How much soy protein is recommended for daily consumption?»
- What is the status of the Food and Drug Administration (FDA) soy heart health claim?»
- What exactly makes soy heart-healthy?»
- Is soy protein a complete protein?»
- How can consumers determine how much soy protein is in a food?»
- Is there an FDA recommendation for daily isoflavone intake?»
- Is soymilk recommended for infants?»
- Are soyfoods recommended for toddlers and older children?»
- Do isoflavone supplements provide the same benefits as eating soyfoods?»
- Does soy increase the risk of breast cancer?»
- Is it possible to consume too much soy protein?»
- Is the use of soyfoods associated with gastrointestinal disturbances?»
- Does consuming soy affect hormone levels?»
- What is the relationship between soy and thyroid function?»
- Is it possible that soy could have negative health effects on men?»
- What is the relationship between soy intake and prostate cancer?»
- Is soy infant formula safe?»
- Could avoiding soy impact the thyroid function of a person with Hashimoto’s disease?»
- Are soyfoods safe for breast cancer survivors to consume?»
ANSWERED QUESTIONS
Does soy increase the risk of breast cancer?
Answered by Katy Raneri, MS, RD - October 5, 2011
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
Featured Expert
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 >>
References
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.