Does Soy Cause Breast Cancer or Make it Worse?

October is Breast Cancer Awareness.

I am personally saddened to see so many women getting this disease. In my own practice, I see younger and younger women with breast cancer coming for immune support while they bravely undergo chemotherapy, surgery and radiation.

I honor these women’s courage.

In this post and next week’s post, I’m going to discuss topics relevant to breast cancer.

Does Soy cause breast cancer or make it worse?

For years my patients have been worried that eating soy might contribute to breast cancer, or in women who have had breast cancer might stimulate a recurrence. More and more evidence is coming out now to the exact contrary. In fact it appears that soy reduces the incidence of breast cancer or its recurrence.

Let me review some of the latest findings.

Most of the health concerns about Soy come from its concentration of phytoestrogens which are group of natural compounds that resemble estrogen chemically.

It is important to know that phytoestrogens only very weakly mimic estrogen. Most large studies of soy intake have not found that soy causes any harm. This is according to Dr. Anna H. Wu of the University of Southern California School of Medicine. You can see her work here.

In fact, Dr. Wu has found that women who consume an equivalent of about one or two servings of soy daily have a lower risk of being diagnosed with breast cancer or having a recurrence.

Dr.Bette Caan from Kaiser Permanente in California also does research on soy and breast cancer, She is quoted as saying “If people enjoy soy as a regular part of their diet, there’s no reason to stop”. You can read her study here.


Finally the American Cancer Society noted in its recent nutrition guidelines for cancer survivors, that eating traditional soy foods – such as tofu, miso, tempeh, and soy milk – may help LOWER the risk of breast, prostate and other cancers. However they do not recommend soy supplements because they are usually highly processed.

My Colleague Michael Gregor, M.D. reviews all of this information from the medical journal articles in short videos on his Web site. He has given me permission to use his videos from his site on my site for my patients’ and readers’ benefit. I urge you to subscribe to his daily newsletter.

Here is his first video on Soy and Breast Cancer:


His second video below answers the question “Well how much soy is safe then?” Dr. Gregor explains in his video that 3 to 5 servings a day is safe.

Just last week, The New York Times weighed in on the soy issue with the same conclusions.

A year ago the New York Times also had an article giving similar recommendations.

Let me know what you think?

Next week, I will take a look at a big risk factor for breast cancer,that is easy to remove.

About Dr. Soram Khalsa

As an MD, Dr Soram specializes in Integrative Medicine combining diet, nutrition, acupuncture, herbs and nutrition. Visit Dr Soram’s Healthy Living Store where you’ll find high-quality nutritional supplements: