All three human studies on soy and breast cancer survival suggest that soy in sufficient amounts may improve survival in women diagnosed with breast cancer.
Breast Cancer Survival and Soy
What about soy food intake and breast cancer survival? We didn’t have a clue, until 2009, when the LACE study was published—Life After Cancer Epidemiology.
About 2,000 California breast cancer survivors followed for nine years. Postmenopausal women, on the estrogen–blocking drug tamoxifen, who got the most of this soy isoflavone in their diet had the lowest rate of breast cancer recurrence—appeared to cut breast cancer recurrence in half. Soy was, if anything, protective. But you can’t just sprinkle some soy sauce. It took soy levels “comparable to those consumed in Asian populations”—one or two servings a day—to reduce the risk of occurrence.
Then came the famous Journal of the American Medical Association study, the biggest yet—5,000 breast cancer survivors. Conclusion: “Among women with breast cancer, soy food consumption was significantly associated with decreased risk of death and recurrence.”
Now this isn’t taking soy isoflavone supplements; this was actually eating soy foods. “[T]he potential benefits are confined to soy foods, and inferences should not be made about the risks or benefits of soy-containing dietary supplements. Patients with breast cancer can be assured that enjoying a soy latte or indulging in pad thai with tofu causes no harm, and, when consumed in plentiful amounts, may reduce [the] risk of disease recurrence.”
And then, finally, 2011: “Soy Food Consumption and Breast Cancer Prognosis.” A third study—the only three such studies in existence—and soy is three for three. “As isoflavone intake increased, risk of death decreased.” What more do we need to know?
To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video. This is just an approximation of the audio contributed by veganmontreal.
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- Guha N, Kwan ML, Quesenberry CP Jr, Weltzien EK, Castillo AL, Caan BJ. Soy isoflavones and risk of cancer recurrence in a cohort of breast cancer survivors: the Life After Cancer Epidemiology study. Breast Cancer Res Treat. 2009 Nov;118(2):395-405.
- Shu XO, Zheng Y, Cai H, Gu K, Chen Z, Zheng W, Lu W. Soy Food Intake and Breast Cancer Survival. JAMA. 2009 Dec 9;302(22):2437-43.
- Ballard-Barbash R, Neuhouser ML. Challenges in design and interpretation of observational research on health behaviors and cancer survival. JAMA. 2009 Dec 9;302(22):2483-4.
- Caan BJ, Natarajan L, Parker B, Gold EB, Thomson C, Newman V, Rock CL, Pu M, Al-Delaimy W, Pierce JP. Soy food consumption and breast cancer prognosis. Cancer Epidemiol Biomarkers Prev. 2011 May;20(5):854-8.
What about soy food intake and breast cancer survival? We didn’t have a clue, until 2009, when the LACE study was published—Life After Cancer Epidemiology.
About 2,000 California breast cancer survivors followed for nine years. Postmenopausal women, on the estrogen–blocking drug tamoxifen, who got the most of this soy isoflavone in their diet had the lowest rate of breast cancer recurrence—appeared to cut breast cancer recurrence in half. Soy was, if anything, protective. But you can’t just sprinkle some soy sauce. It took soy levels “comparable to those consumed in Asian populations”—one or two servings a day—to reduce the risk of occurrence.
Then came the famous Journal of the American Medical Association study, the biggest yet—5,000 breast cancer survivors. Conclusion: “Among women with breast cancer, soy food consumption was significantly associated with decreased risk of death and recurrence.”
Now this isn’t taking soy isoflavone supplements; this was actually eating soy foods. “[T]he potential benefits are confined to soy foods, and inferences should not be made about the risks or benefits of soy-containing dietary supplements. Patients with breast cancer can be assured that enjoying a soy latte or indulging in pad thai with tofu causes no harm, and, when consumed in plentiful amounts, may reduce [the] risk of disease recurrence.”
And then, finally, 2011: “Soy Food Consumption and Breast Cancer Prognosis.” A third study—the only three such studies in existence—and soy is three for three. “As isoflavone intake increased, risk of death decreased.” What more do we need to know?
To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video. This is just an approximation of the audio contributed by veganmontreal.
Please consider volunteering to help out on the site.
- Guha N, Kwan ML, Quesenberry CP Jr, Weltzien EK, Castillo AL, Caan BJ. Soy isoflavones and risk of cancer recurrence in a cohort of breast cancer survivors: the Life After Cancer Epidemiology study. Breast Cancer Res Treat. 2009 Nov;118(2):395-405.
- Shu XO, Zheng Y, Cai H, Gu K, Chen Z, Zheng W, Lu W. Soy Food Intake and Breast Cancer Survival. JAMA. 2009 Dec 9;302(22):2437-43.
- Ballard-Barbash R, Neuhouser ML. Challenges in design and interpretation of observational research on health behaviors and cancer survival. JAMA. 2009 Dec 9;302(22):2483-4.
- Caan BJ, Natarajan L, Parker B, Gold EB, Thomson C, Newman V, Rock CL, Pu M, Al-Delaimy W, Pierce JP. Soy food consumption and breast cancer prognosis. Cancer Epidemiol Biomarkers Prev. 2011 May;20(5):854-8.
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Breast Cancer Survival and Soy
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Content URLDoctor's Note
This is the fifth in my five-part series on the latest research on the impact of diet on breast cancer survival. For two videos on what not to eat, see: Breast Cancer Survival, Butterfat, and Chicken, and Breast Cancer Survival and Trans Fat. And soy joins flax seeds as something breast cancer survivors should probably go out of their way to eat; see Breast Cancer Survival and Lignan Intake, and Flax and Fecal Flora. There are many more videos on soy.
Note also that the JAMA study is open access, so you can download it by clicking on the link in the Sources Cited section, above.
For more context, check out my associated blog posts: Breast Cancer Survival and Soy; How Much Soy Is Too Much?; Are Bioidentical Hormones Safe?; Gerson Therapy for Cancer?; How Tumors Use Meat to Grow; Mushrooms for Breast Cancer Prevention; Why Less Breast Cancer in Asia?; Foods That May Block Cancer Formation; Flax and Breast Cancer Survival, and Breast Cancer & Alcohol: How Much Is Safe?.
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