breast cancer and tofu, how much is too much?

Hi and thank you for answering my question.  I am a 46yo who had estrogen - breast cancer 6 years ago with no nodes involved.  I was treated at the time with chemotherapy and radiation which helped me begin menopause.  For the past five years I have been eating a diet rich in soy products and I find that it really helps with menopausal symptoms as well as weight management. I eat about two servings of tofu and two of flax seed bread a day.  I have recently heard about research showing that soy causes breast cell proliferation and thus may not be healthy for women with breast cancer!  Of course, I started eating it in the first place to help PREVENT a recurrence! The research I have read is confusing at best and my guess is that they really just don't know yet.  My oncologist says tofu is fine in moderation but I never really found out what 'moderation' meant. Also, my 19 year old daughter has started eating a lot of tofu as well, and I wonder if it would be contra indicated for her. I would really appreciate any thoughts that you have on this confusing subject.  Thanks again for your time.

[CCF-RN,MSN-JS]

Dear eyeball, The basis for considering dietary soy in prevention of cancer, or recurrence is based on studies of populations that regularly consume soy-based foods.  These populations show markedly lower incidence rates for breast, colon, and prostate cancer, when compared with populations with lesser intake of soy products.   Various studies have been done looking at the different components of soy which have both estrogen like and estrogen blocking features which is what makes the data confusing.   Overall, the current data are insufficient to draw definite conclusions about the use of soy as preventive agent against breast cancer or breast cancer recurrence.  

As to the term moderation, in Dr. Susan Love

[dmiller3014]

I was also increasing my intake of soy products based on the promotional advertising I was seeing on TV. Mostly soy milk in protein shakes. Then my husband came across some research that basically said our government did studies years ago on soy benefits and the results showed the negatives far outweighed the benefits. It said there was a much estrogen in a glass of soy milk as there is in a birth control pill. Also, something I had already known is that soy is not a natural human food. Human beings can't digest soy raw. It has to be cooked, otherwise it is poisonous. The only animals that can eat it have rudimentary stomachs. (Cows and sheep) I have come to believe we should eat as much raw food as possible, so this ruled out soy products for me. Obviously someone is lobbying heavily to have soy being promoted to the extent that it is today. As usual, our government watches whose toes they step on. I would do more research before I continue consuming soy products of any kind.

[Debster]

I had DCIS breast cancer, which is Ductal Carcinoma. The oncologist told me not to consume soy and flaxseed products because of their estrogen factors. I was very disappointed because I'm perimenopausal and they always made me feel better. I asked him why and he said my particular type of cancer is estrogen fed and too much of these products would increase my chances of the same in the other breast. So I guess it depends on what type you had if these products are good or not, that's why there are conflicting reports.