Soy or no Soy?

omigod...now i have to worry about soy too?? by the way...has anyone found a multivitamin that does NOT have antioxidants in it? has anyone tried immpower (supplement) to boost the immune system. the pharmacist at the hospital where i work swears by it...

My oncologist said to avoid all antioxidants (except those naturally occuring in foods) since it works against the chemo and can neutralize the effects of the chemo drugs.

Hello ladies- very interesting thread. Before I was dx in 2004 I was on a high soy diet monitored by a weight loss Dr. LOTS of Soy ISOLATE and Isolated soy products. Since having bc I have eliminated the "isolates" and the isolated from my diet. It is the natural soy LECITHIN that I have come to understand that with moderation is ok. HOWEVER- I am triple negative and still find it hard to consume soy voluntarily. I lost 32 lbs on the diet. But gained 1/2 of it back on chemo. (mood foods) and have been trying to just eat healthier. Like you all have said here, soy is in EVERYTING! Even Tuna! But they are not the processes ones (isolates) so- I'm eased about that. I'm more focused now on getting enough fiber and protien in my body. I was also told and have read that supplements should be avoided too. Good luck to you all...
Nicki

Thanks for the reply HollyHopes. Hope you are doing well with your chemo.

Nicki,

The information about the soy processing came from a baby formula maker. I asked them a question about why they put soy in their organic formula, and they said they have to list it because a trace amount might be in there from the processing plant. Then they went on to explain why we shouldn't eat soy and you see the quote above from them about the hexane in the normal processing. That's the kind we get to eat which is in everything lately.

I just try to stay away from it, but I'm very upset that there is any soy in baby formulas and food stuffs.

About finding stories on the net. I use yahoo, and just ask a question. Is soy safe to eat? and up will come a few hundred hits.

I got conflicting advise from all medical personnel, and I am estrogen positive. I finally found a great nutritionist who works with cancer patients and she explained soy to me. Soy had been one of the major sources of protein in my diet prior to diagnosis.

What I was told that two or three small servings of soy products, i.e., tofu, per week, and small being the operative word, will not harm you. The thing to watch out for are all of the soy based supplements and vitamins, which you should avoid like the plague if you are ER+. The reason is the amount of soy in vitamins and supplements is not regulated, and you really have no idea of what you are getting, whereas you know exactly what you are getting with a 3 oz. portion of tofu.

Hope this helps! I have switched to all non-soy based vitamins and supplements and there are a lot of great products out there.

Take care,

Valerie R

What that story is saying to me is that all of us should be wary of estrogen, even the ER negatives. That is new that even a small amount of estrogen can turn off our immunity system to produce natural killer cells.

I don't think soy will be the answer because the unfermented kind has genistein in it which promotes the growth of tumors. Maybe if they use the fermented type, maybe:

http://www.ncbi.nlm.nih.gov/entrez/query...t_uids=11431339

I just found an article that discusses human clinical trials with soy on mice (of course) and humans with prostate cancer. Prostate cancer has a lot of similarities to bc, so we might think about extrapolating the results to us.

The researchers claim that the whole soy supplement reduced proliferation of the tumor cells, while genistein (a single isoflavone found in soy) promoted tumors.

For what it's worth:

http://www.aicr.org/site/News2?abbr=res_&page=NewsArticle&id=11327&news_iv_ctrl=1201
Boosting Cancer Treatment via Food Compounds

some excerpts:

In laboratory studies, Dr. Sarkar found that genistein along with chemotherapy promoted apoptosis in treated cells, compared to cells treated with genistein or chemotherapy alone.
........
Supported by an AICR grant, Dr. Hillman found that genistein combined with radiation treatment inhibited cancer cell growth significantly more than radiation or genistein treatment alone.

But the researchers discovered that genistein, when given without radiation therapy, promoted metastasis from prostate tumors to the adjacent lymph nodes. "This increased metastasis was a big concern, because we were already running clinical trials using soy," Dr. Hillman notes. In the human trials, no adverse effects were seen.
........
An important difference between the clinical and laboratory studies was that the mice had been treated with a solution of pure genistein, while the people received capsules containing whole soy powder. That difference proved to be key. When Hillman switched the mice to dried powder of whole soy, she found whole soy just as effective as genistein in radiosensitizing prostate tumors. Also, whole soy given without radiation did not increase metastasis to the lymph nodes.
......
In addition to genistein, researchers are investigating the sensitizing characteristics of other dietary agents. Curcumin, a phytochemical found in turmeric; indole-3-carbinol, an antioxidant found in cruciferous vegetables; EGCG, a flavonoid found in green tea; and resveratrol, a compound found in grape seeds and red grape skins, are among the substances shown to enhance the antitumor activity of various chemotherapeutic drugs. Research combining these dietary compounds with chemotherapeutic agents shows increased apoptosis and decreased proliferation in tumor cells from colorectal, liver and ovarian cancers.

In laboratory studies, genistein, curcumin, gamma-tocotrienol - a vitamin E component - and PABA (para-aminobenzoic acid), are among the dietary agents shown to sensitize cancer cells to radiation treatment. This enhanced radiosensitivity has been shown in prostate, cervical, esophageal, breast and melanoma cancer cells.

The question is what would be different about the 13% of women who get breast cancer from the 87% who don't. They all have exposure to pesticides? If pesticide had that great an impact the incidence of BC would be greater.Most smokers do not get cancer, so again the question is what is unique about their biology in the broadest sense? Beth

I spoke with my onc who has done collaboration with Karmonos on this issue and in his opinion the results are very unclear. He does not want me on soy, but says normal intake of any fruits or vegs is fine during treatment.

I found something more current.
Mol Carcinog. 2007 Feb 12;
Genistein sensitizes inhibitory effect of tamoxifen on the growth of estrogen receptor-positive and HER2-overexpressing human breast cancer cells.

* Mai Z,
* Blackburn GL,
* Zhou JR.

Nutrition/Metabolism Laboratory, Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts.

Although tamoxifen (TAM) is used for the front-line treatment and prevention of estrogen receptor-positive (ER+) breast tumors, nearly 40% of estrogen-dependent breast tumors do not respond to TAM treatment. Moreover, the positive response is usually of short duration, and most tumors eventually develop TAM-resistance. Overexpression of HER2 gene is associated with TAM-resistance of breast tumor, and suppression of HER2 expression enhances the TAM activity. Soy isoflavone genistein has been shown to have anti-cancer activities and suppress expression of HER2 and ERalpha. The objective of this study was to test the hypothesis that genistein may sensitize the response of ER+ and HER2-overexpressing breast cancer cells to TAM treatment. The combination treatment of TAM and genistein inhibited the growth of ER+/HER2-overexpressing BT-474 human breast cancer cells in a synergistic manner in vitro. Determination of cellular markers indicated that this synergistic inhibitory effect might be contributed in part from combined effects on cell-cycle arrest at G(1) phase and on induction of apoptosis. Further determination of the molecular markers showed that TAM and genistein combination synergistically induced BT-474 cell apoptosis in part by synergistic downregulation of the expression of survivin, one of the apoptotic effectors, and downregulation of EGFR, HER2, and ERalpha expression. Our research may provide a novel approach for the prevention and/or treatment of TAM insensitive/resistant human breast cancer, and warrants further in vivo studies to verify the efficacy of genistein and TAM combination on the growth of ER+/HER2-overexpressing breast tumors and to elucidate the in vivo mechanisms of synergistic actions. (c) 2007 Wiley-Liss, Inc.

Effect of broccoli, soy on cancer cells explained

April 16, 2007 06:36:29 AM PST

Eating foods like broccoli and soy has been linked to lower cancer rates, and California researchers said on Sunday that they may have discovered the biological mechanism behind the protective effect.

Using cells in a lab dish, researchers at the University of California, Los Angeles, found that diindolymethane (DIM), a compound resulting from digestion of cruciferous vegetables, and genistein, an isoflavone in soy, reduce the production of two proteins needed for breast and ovarian cancers to spread.

"We think these compounds might slow or prevent the metastasis of breast and ovarian cancer, which would greatly increase the effectiveness of current treatments," said Erin Hsu, a UCLA graduate student in molecular toxicology.

The UCLA team, which reported its finding at a meeting of the American Association for Cancer Research, will next test the theory in mice.

The findings highlight "an entirely unique mechanism ... Preventing the invasion and metastasis of cancer cells is crucial," said Dr. Alan Kristal, associate head of the cancer prevention program at Fred Hutchinson Cancer Research Center in Seattle.

Cancer cells express very high levels of a surface receptor known as CXCR4, while the organs to which the cancers spread secrete high levels of CXCL12, a ligand that binds to that particular receptor.

This attraction stimulates the invasive properties of cancer cells and acts like a homing device, drawing the cancer cells to organs like the liver or brain.

The study found that when cancer cells were treated with either DIM or genistein, movement toward CXCL12 is reduced by at least 80 percent compared to untreated cells.

Hsu says that this same chemotactic attraction is thought to play a role in the development of more than 23 different types of cancer.

The amount of DIM and genistein used in the study is probably comparable to use of a high dose of supplements, and is likely not achievable through consumption of food alone, the researchers said.

Both DIM and genistein are already being developed for use as a preventive, and a chemotherapy treatment for breast cancer, although more extensive toxicological studies are needed, they added.

Wow, I just read Soy Alert That Lilly suggested and in the article it said, "Soy foods increase the body's requirement for vitamin D." Wasn't there just some findings that women with breast cancer had very low vitamin D in thier bodies?

Vitamin stores would have DIM. They still have a lot more explaining to do about genistein. They can't have it both ways, does it increase the size of a tumor or decrease it?

Bringing this back to the top since it's such an interesting topic for me.

I didn't want to have my dx hanging around my sig, but I am ER+/PR+/Her2-.  The estrogen was very highly receptive (like 100%). So I am also looking at making some dietary changes. Ironic that I was just starting to bring in more soy products into my diet to help me in my menopause (I'm 56).

So, no edaname?