Are soy products bad for breast cancer?

Cat123

Hi all, 

I am so confused about whether or not to eat soy products.  I have read so much conflicting information.  I turned vegan when I was diagnosed so it's difficult to not eat tofu, soy milk (I use other non-dairy alternatives but in restaurants they serve soy milk), soy burgers, etc.  I am very ER positive, 97% I believe ,so will soy affect my bc?  There are low instances of bc in asian countries where alot of soy is consumed so it doesn't make sense, however, I read about soy being a phytoestrogen.  I read in one book that phytoestrogens are good because it gets rid of estrogen and other books say it mimics estrogen.  The last update on Dr. Love's site says that soy is alright.  All the info is so confusing.  What do you think?  Has anyone heard anything from an onc or naturopath that you could share?  Thanks so much!

GG27

I'm no expert, I can only tell you what the breast cancer nutritionist told me.  She said that food soy was fine, like soy milk, tofu, edamame etc.  She said to avoid all soy & protien powders.  HTH a little. Dee

Cat123

That's interesting mfrog....I guess she means no processed soy.

GG27

I'm sorry I didn't listen a bit better, I've never been a big soy person.  Also there was a woman there who made the whole thing about her, it was a group class of about 25 of us, so I ended up tuning out.

There should be a nutrition course offered at your local cancer agency, perhaps give them a call.  I was able to call a nutritionist directly to ask about ground flax which I eat everyday & was worried about.

Member_of_the_Club

I was also told some in the diet is fine (I like tofu) but don't take supplements or drink soy milk.

Victoria67

Hi mfrog, do you mind if i ask what your nutritionist said about flaxseed?  I'm curious about that too.

althea

I've gone round and round on the soy issue.  Currently, I'm in the 'not doing soy' camp.  One reason is my underactive thyroid.  Soy is a goitrogen, which means it interferes with your thyroid's ability to take in iodine which it needs for proper function.  Another reason is the ubiquitousness of soy in our foods.  ....or as Michael Pollan says, food-like substances. 

Unless you're making every last morsel of your food from scratch or eating raw, uncooked foods, you'll be consuming soy at nearly every mouthful.  It diminishes attempts to have variety in what we eat.  But what is truly ominous is the fact that 80 to 90% of USA grown soy is genetically modified. 

Have you heard of the phrase 'round-up ready?'  Soy is a 'round-up ready' crop.  I have several reasons for avoiding soy, but truly, I don't need any other reason than GMO to say no to soy.  

bdavis

This was the lunch table conversation yesterday.. I work at a school for this whole week they are serving a vegetarian lunch... extensive lunch... and of course there is tons of soy products. It was the lunch table concensus that soy was not a good thing for BC... plus my onc said so last week... said adding soy sauce to my meat is fine, but everything in moderation... so no soy supplements.

GG27

Victoria67,  She said that the jury is out on ground flaxseed, there is no real evidence one way or the other for recurrance.  Her recommendation was to limit intake to 1 tsp per day, she said no problem for flaxseed themselves, apparently they pass through.   Dee

Husband11

There is no clear answer yet.  The population study from Asia that is touted as showing that it is ok, may not apply to women who have a different history of soy consumption.  The asian women who consumed high amounts of soy after diagnosis, likely consumed high amounts of soy througout their prior lives.

barbe1958

The whole Asian study negates the fact that the Asians consumed soy since BIRTH. They didn't all of a sudden add it to their diet. For them, it can stave off a bc diagnosis. For someone to all of a sudden add it, it may start off a ER+ breast cancer. ER+ cancers shouldn't be fed the very thing that it needs. We often see women diagnosed while pregnant or just after, when all those hormones just fed the cancer.

Not ALL things "natural" are good for you. Especially when your eyes are opened. Why play with fire?

revkat

The theory that the Asian study doesn't apply to other women because they had been eating soy since birth and western women haven't is only a theory. Also, logically, if everything we we eat has soy in it then we too have been eating soy all along, just not in whole food form.

This is an unresolved question (unlike the alcohol consumption question). There is no medical evidence to suggest that eliminating whole soy foods from your diet will reduce your risk of BC or of BC recurrence.

dreaming

At the Cancer Center where I work, we tell patients that soy has hormones and if your cancer is positive for hormones NOT to take,use anything that has hormones,including beauty,herbal products.

barbe1958

Revkat, it's not a theory. That's why soy hit the forefront. It was "believed" to ward off cancer.

pip57

The soy that Asians eat is very different from our GM soy that is refined and processed.  No comparison.

Anonymous

I would get a referral to see a dietitian that specializes in BC.  I did.  I was encouraged to eat soy - in natural form, but I am ER/PR negative.  Everyone is different and there is no general answer.

The answer depends on your specific circumstances.  please get your advice from a medical professional

barbe1958

And make sure you tell "whoever" it is that you are ER+. That makes a HUGE difference!

Anonymous

YES.  Bring your pathology report.  My dietitian wanted to see mine

revkat

I have not seen studies that showed that soy is metabolized differently depending on how much you have eaten in your lifetime.

My local chain grocery stores all sell USA grown, non-GMO tofu and edamame.

How phytoestrogens interact with ER+ breast cancer is still an unknown. Theoretically it is possible that they stimulate growth. Theoretically it is also possible that they inhibit growth by competing for receptors with your own estrogen (which is much stronger).

Whatever soy's effects are on bc, it is likely to be minimal. It troubles me that so much energy goes into worrying about soy and not into the things that have been shown to have a statistical effect on bc -- maintain a normal body weight, exercise daily, don't drink alcohol, don't take hormone replacement medications.

If you like soy, eat whole food forms in moderation. If you don't like it, don't eat it. 

barbe1958

Again, it's not the point of how much you've eaten in your lifetime, but that you started as an infant and built it up.

barbe1958

Also, I don't know how a US company can say non-GMO when Monsato owns each and every seed used in the US. They have GMO'd everything to death. And soy was their brainchild.

Lowrider54

At stage iv and taking anti hormonals - soy is a no-no - flax seed too (although I don't know the flax story).  Soy is in so many products it is difficult to avoid it altogether but I try - just avoid the big ones - soy beans, soy milk, soy sauce and any product that is primarily soy.  The icky part is being stuck with the supplement tablets as the gel caps are made of soy. 

revkat

Barbe, I don't know where you are getting your information, but non-GMO soy is grown in the US. It actually has a premium price on it for growers due to the non-GMO food movement. Yes, Monsanto is huge and evil, but even so they do not control all the agriculture in the US. Just a lot of it.

Maybe you can help me by finding the study that shows that soy has different effects on your body based on when you began eating it in life. I haven't found that study, only hypotheses that it might attached to discussions of the Asian study.

I know that different doctors and different nutritionist are making different recommendations about soy to their patients. I just haven't seen convincing evidence to say that eliminating whole soy foods makes any difference, even with regard to ER+ breast cancer.  

lago

If I have to give up the hot & sour soup at Sun Wah and never eat sushi with soy sauce I am not going to be a happy camper. Granted these are not things I eat daily (but wouldn't mind a daily diet of sushi ).

I do eat a lot of Asian food but some of it is made with fish sauce. Most times I will ask for low salt, less oil which means they put less soy sauce and use less oil in the dish.

OK so now I'm going to have my healthy salad for lunch: romaine lettuce, red cabbage, carrot, dried corn, craisins, goat cheese, avocado, walnuts topped with my home made dressing of balsamic vinegar, little bit of virgin olive oil, salsa, basil and water. See I do eat healthy most of the time. I'll try an update this post with a photo after I make it.

and as far as alcohol I found this article interesting on medcape (Alcohol May Increase Risk for Breast Cancer Recurrence by Roxanne Nelson). Link won't work but if you google it you can get to it.  I don't think a drink every one in a while will hurt especially for those of us who  have managed to maintain a healthy weight.

dlb823

I'm highly ER+ and both the integrative specialist & nutritionist at UCLA teach that natural soy foods, in moderation, are fine.  Like Dee, I was told no soy protein or soy protein products (like energy bars) that contain soy protein isolates.  The reason is that isolates are a highly concentrated form of soy that is no longer natural.

I share Althea's GMO concern, and also a fact I read somewhere about soy crops being heavily sprayed with herbicides and pesticides, to the point that some soy products might be quite contaminated.  So I try to stick with organically labeled soy products, as well as organic nutritional supplements, if they contain soy, which is a common ingredient in many of them.     Deanna

barbe1958

Okay, I typed "soy and breast cancer" into Google. Here are some excerpts:

Soy Chemistry Controversy - Isoflavones
Soybeans contain all the amino acids essential to human nutrition. Soy foods contain isoflavones (phytoestrogens). These isoflavones have powerful antioxidant properties, and may be able to prevent cell damage (oxidation) caused by free radicals. Soy isoflavones can act like weak estrogens, and may block estrogen receptors, similar to the way that tamoxifen works to prevent a recurrence of estrogen-sensitive breast cancer. Sounds great, doesn't it? But there may be a problem of "too much of a good thing." Just as an excess of natural estrogen may fuel the growth of a breast tumor, too much of the soy isoflavone genistein, in concentrated form in many over-the-counter nutritional supplements, may set the stage for tumor development. But what about Asians who grow up on tofu? Let's look at their rates of breast cancer.

The Well-Polished Chopstick - A Lifetime of Soy and Green Tea
Japanese women typically consume soy beginning in childhood, which may be a key to prevention of breast cancer. In April of 2008, a Japanese study was published on soy consumption and rates of breast cancer. In this study, Dr. Iwasaki and his team recruited 24,226 Japanese women aged 40 to 69. Their study covered 10.6 years, and the women in the study did not keep a food journal, which is sometimes an unreliable component of such a study. The researchers used blood and urine samples to measure isoflavone levels. Women who had the most consistently high levels of genistein (isoflavone from soy) had the lowest rates of breast cancer.

Dietary Soy Versus Soy Supplements
The isoflavones found in soybeans, sesame seeds, and legumes are about one hundredth as powerful as natural female estrogens. If you're getting your isoflavones from dietary sources, you'd have a hard time overdosing yourself, unless you went on an all-soy diet. So wouldn't those capsules containing soy isoflavones that are sold as hormonal support and bone health protection be safe? The answer is: it depends. Pills with isolated soy isoflavones may cause trouble - not enough studies have been done yet on people to determine whether or not high concentrations of those isoflavones may encourage the growth of breast cancer. If you're taking soy supplements to help with menopausal symptoms, speak with your doctor about what level of isoflavones may be safe for you.

Here's another one:

The Start of the Soy Concept

There are a lot of questions raised with regards to soy. Some people ask if women who survived breast cancer should start avoiding eating tofu and other soy products. Also, is it true that if a person wants to stay away from this cancer they should avoid drinking soy powdered milk? The concept about soy and how they can promote cancer is very confusing and still no concrete answer to this question. Thus, the relevancy of soy to breast cancer is will connected with estrogen that acts like a stimulant that can be a receptors of breast cancer cells that can make them grow. There is always a potential if you eat a lot of soy products when you have cancer, and this is why most doctors will advice women who are undergoing breast cancer to avoid eating soy products. In contrary, some say that soy is not harmful. It can actually protect women from cancer because of its component isoflavones that can give a good strength in your body system. Soy products in considered as of the healthiest food due the protein content that will make your body strong and can build your muscle tissues.

And another: (how many do you want?)

Whether soy can help protect against breast cancer in post-menopausal women is unclear at this time. Some researchers believe that soy consumption may actually increase the risk for breast cancer in post-menopausal women because the chemical structure of plant estrogens (phytoestrogens) is very similar to estrogen. Jeanne Petrek, MD, surgeon and breast cancer specialist at Memorial Sloan-Kettering Cancer Center in New York, recently told the American Cancer Society that phytoestrogens could possibly be misinterpreted by the body as estrogen and increase the risk of breast cancer in post-menopausal women. ⁽¹⁾

barbe1958

Oh, I Googled "GMO soy" as well. I was mistaken, only 91% of soy seeds are GMO but the rest are sprayed so much that that will kill you. Here's an excerpt:

GMO soy is destroying land and the environment

It is not only people that are bearing the brunt of biotech greed, though; the environment in South America is suffering tremendously as well. Sensitive ecosystems like the Amazon Rainforest and the Cerrado, a large and very fragile savannah, have been bulldozed in many areas to make room for more GMO soy. And there is no end in sight to this practice.

In Brazil, 1.2 million hectares of rainforest have already been leveled to cultivate GMO soy. And in Argentina, about 18 million hectares of land are now growing the crop, which represents more than half of the nation's entire growing areas. And all of the GMO crops, as well as many non-GMO crops, are regularly doused in highly dangerous chemical pesticides, which ruin both the environment and human health.

"In Brazil, the toxic and hazardous pesticides paraquat and endosulfan are still used," explained Jaime Weber, a friend of Geleano that works to promote sustainable and non-toxic organic agriculture in Brazil. "It is a myth that these are not used on GM crops. GM soybeans are sprayed just as much with paraquat [as non-GM]."

Paraquat is linked to Parkinson's disease and other neurological disorders (http://www.naturalnews.com/026177_Parkinsons_disease_pesticides.html) while endosulfan is known to disrupt the endocrine system.

"Both the spraying of conventional farming and GMO cultivation [pose] severe health risks to farm workers and those living around the fields," added Weber, noting that the large, industrial farms routinely violate safety standards and spray in irresponsible and dangerous ways because they know they can get away with it without penalty.



Learn more: http://www.naturalnews.com/030390_GMO_soy_poverty.html#ixzz1CGsFvfsM

barbe1958

Oh goodie!! That one included a link.

I'm not an idiot revkat...

lago

Is there less incidence of breast cancer in Japanese women due to soy consumption or is it because they eat very little dairy (less fat)?

barbe1958

VERY good point Iago!!! See, that's where rumours about "good things" come from. Like on the other thread where is said that 60 out of 10 MILLION women with breast implants get Lymphoma from the implant. I bet 60 out of ANY 10 million people would get Lymphoma!!

I drive a car + I have breast cancer = Driving a car caused my breast cancer. Give me a million dollar grant and I'll prove it!

barbe1958

Hang on!! As a passenger in a car, the seatbelt would have rubbed exactly under my breast where my tumour grew....I may be on to something! BUT, am I a passenger more than a driver, or less......??