GMO Soy and Breast Cancer

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GMO Soy & Breast Cancer

In response to concerns raised about the toxicity of Monsanto’s roundup pesticide, which ends up in GMO foods (See Is Monsanto’s Roundup Pesticide Glyphosate Safe?), Monsanto’s scientists countered that these in vitro experiments used physiological irrelevant concentrations, meaning dripping roundup on cells in a petri dish at levels far above what would be realistically found in the human body.

Sure, it’s probably not a good idea to mix up your alcohol with your roundup and chug the stuff, or try to commit suicide by drinking or injecting it. And there are rare cases of Parkinson’s reported after getting directly sprayed with it, or working for years in a pesticide production plant, but that’s not your typical consumer exposure.

As shown in my video GMO Soy and Breast Cancer, some of the researchers responded to the accusation claiming they used the kinds of concentrations that are used out in the fields. Therefore every little droplet we spray worldwide is above the threshold concentration they found to cause adverse effects. Monsanto’s folks responded saying, “Yes, that’s the concentration we spray, but that’s not the concentration that human cells are bathing in. Once it gets into drinking water or food, it’s highly diluted.” And, they’re quick to point out, if we look at people with the greatest exposure—pesticide workers—the vast majority of studies show no link between the use of Roundup and cancer or non-cancer diseases. There are a few suggestive findings suggesting a link with non-Hodgkin’s lymphoma. One study of pesticide applicators suggested an association with multiple myeloma, and one study of the children of pesticide applicators found a tentative association with ADHD, but again these are folks experiencing a much greater exposure level than the general population that may just get a few parts per million in their food. But there had never been any studies done on the tiny levels found circulating in people’s bodies, until now.

In a study out of Thailand, the maximum residue levels were set at parts per million (the concentrations found within human bodies is measured in parts per billion). The study found glyphosate can activate estrogen receptors at a few parts per trillion, increasing the growth of estrogen receptor positive human breast cancer cells in a petri dish. These results indicate “that truly relevant concentrations of the pesticide found on GMO soybeans possesses estrogenic activity.”

But consumption of soy is associated with lower breast cancer risk (See BRCA Breast Cancer Genes and Soy), and improved breast cancer survival (See Breast Cancer Survival and Soy).

That may be because most GMO soy in the U.S. is fed to chickens, pigs, and cows as livestock feed, whereas most of the major soy food manufacturers use non-GMO soy. Or it could be because the benefits of eating any kind of soy may far outweigh the risks, but why accept any risk at all when we can choose organic soy products, which by law exclude GMOs.

The bottom-line is that there is no direct human data suggesting harm from eating GMOs, though in fairness such studies haven’t been done, which is exactly the point that critics counter. This is why we need mandatory labeling on GMO products so that public health researchers can track whether GMOs are having any adverse effects.

It is important to put the GMO issue in perspective though. As I’ve shown (See Lifestyle Medicine: Treating the Causes of Disease), there are dietary and lifestyle changes we can make that could eliminate most heart disease, strokes, diabetes, and cancer. Millions of lives could be saved. A healthy enough diet can even reverse our number one killer, heart disease. So, I’m sympathetic to the biotech industry’s exasperation about GMO concerns when we still have people dropping dead from everything else they’re eating. As one review concluded “consumption of genetically modified food entails risk of undesirable effects… similar to the consumption of traditional food.” In other words, buying the non-GMO Twinkie isn’t doing our body much of a favor.

For more on the public health implications of genetically engineered crops in our food supply, check out the these videos:

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live year-in-review presentations Uprooting the Leading Causes of DeathMore Than an Apple a DayFrom Table to Able, and Food as Medicine.


Michael Greger M.D., FACLM

Michael Greger, M.D. FACLM, is a physician, New York Times bestselling author, and internationally recognized professional speaker on a number of important public health issues. Dr. Greger has lectured at the Conference on World Affairs, the National Institutes of Health, and the International Bird Flu Summit, testified before Congress, appeared on The Dr. Oz Show and The Colbert Report, and was invited as an expert witness in defense of Oprah Winfrey at the infamous "meat defamation" trial.

34 responses to “GMO Soy & Breast Cancer

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  1. This article completely confounds the purported hazards of consuming GMOs and of consuming pesticides.

    Yet it says “we need” mandatory GMO labeling, but says nothing about pesticide use labeling, mutagenic labeling, or labeling for any of many things that might be considered worrisome by some.

    1. Pesticide in high concentration is known to cause cancer. GMO products are made so that a lot of pesticide can be sprayed on it. In small dose though, there is no clear evidence yet, but we don’t know what can be called low dose and does it accumulate over time as we keep consuming pesticide sprayed products? That’s why we need GMO labeling law so 1) people can avoid GMO products if they want to, and 2) track the effect of GMO product.

      But one thing is that the consumption of beneficial foods, GMO or non GMO, outweighs its risk, so just because a product is not labeled GMO or not, we should not avoid consuming it.

      1. I think that I remember reading something within the past year about a glyphosate study indicating that that parts per million for glyphosaate as an isolated chemical may possibly be boarderline safe, but that there is a synergistic effect between glyphosate and the chemicals that it is mixed with in Roundup, so that the combination is quite toxic at parts per billion levels for humans, not parts per million. This article came out at the time our government was raising the safety limit for the use of glyphosate because higher concentrations appeared to be needed to deal with glyphosate resistant weeds. Does anyone else remember that coming out sometime within the past year or two? If this information is correct it would appear that there may have been some purposeful slight-of-hand being used to divert government regulators awareness as well as public awareness away from the real danger which would appear to be from Roundup, which is an enhanced glyphosate cocktail. that has apparently not had safety studies performed or even required.

      2. Listened to Jeffrey Smith quite a bit and found him to spin the truth a bit too much for me. I feel that some people and sources don’t care about the truth but have an agenda of their own. It seems that fear mongering pays well.

  2. I am normally along side on what the Dr. states, but not this time. I agree in a perfect world end results would be good. I guess he forgets we had perfect food at one time and the stuff your eating that is killings is made and owned by the same people that are doing the GMO.

    1. I agree, Dale. I would also like to know who thinks that Roundup is a pesticide (bug killer), as discussed here and elsewhere in this chain of videos? And who thinks it’s an herbicide (weed killer, not bug killer)? Congratulations to those of you who voted for herbicide – that’s what it is sold as. However, as Yvonne said in a comment on another post, “glyphosate (the active ingredient in Roundup) was originally patented in the 60’s as an ANTIBIOTIC.” Therefore, we should be looking at disturbances in the human biome (gut bacteria). Why aren’t we? Based on recent research in biome performance, such disturbances would lead to autoimmune disfunction, changes in intellect, and problems in digestion. How about some research in those areas, Dr G?

      1. DoctorDave: To address the first part of your post, concerning the definition of a pesticide: I used to think the same way you do. But after someone wrote an explanation on NutritionFacts recently, I looked it up. It appears that the term pesticide is an umbrella term for herbicides, insecticides, and other killers. You learn something new every day!
        I agree that if there were any research into how Roundup might kill the nice little buggies in our guts, that would be very interesting and helpful. Hopefully scientists will branch out in that area soon. (If they haven’t already…)

  3. I’m not “sympathetic to the biotech industy’s exasperation about biotech concerns when we have people dropping dead from everything else they’re eating.” The “public” isn’t just one person. There are people not interested in the facts about their food, but these usually get interested when illness strikes. That’s why there is so much false information telling lies about what is healthy. People need the truth to make decisions, and they need good educations ( both at home and from institutions) to appreciate truth, knowlege and free choice and how those things affect our lives. When certain truths aren’t common knowlege most of us must first grow up and educate ourselves. But there are plenty of people doing their best to educate themselves and understand how to be healthy and how to help others. Those biotech interests are not exasperated because people are just so ingnorant about health, they are exasperated because if GMO labeling is mandatory, many who are trying hard to be healthy and may exercise their right to choose to not to support their industry with our billions of dollars.

  4. This was hyperbolic. I would never suggest trusting Monsanto, and I am for scientific studies and labeling, but simply rinsing your food would make it safe.

    As far as the environment, let’s get the data and create appropriate regulations.

    (PS – I think Dr Gregor does great work, I donated money last year and will do so this year.)

    1. Brillo, I realize THIS article was about the herbicide, but GMO foods cannot simply be rinsed off and suddenly become non-GMO foods. Their whole point is that they have the ability to do what they do built into their genome, into every cell. Those GMO foods which actually kill bugs also kill the bacteria in our guts – bacteria that is crucial to our health and even survival. THEY are labeled as pesticides, yet people eat them every day.

  5. This was disappointing. I realize Dr G is being as fair minded as possible, but you have to consider the entire picture, not just research done by the companies that are profiting mightily from a product. What about the weeds that have become resistant to glyphosate, requiring more and more of the toxin? Where will that end? What about all those pesticides going into the groundwater, being drunk by babies and played in when children splash in the sprinkler? And are we just to toss those agricultural workers off as irrelevant? Come on, Dr G, consider the WHOLE picture, please.

  6. Putin and Russian officials have kicked out Monsanto from Russia. The difference between Putin and America which is really governed by Big Business is that Putin is doing everything he can to make his people, country, and military strong, whereas, Big Business in America is doing everything it can to make a lot of money at the expense of anything and everything. This is why Big Global Business entities are trying to encircle Russia with NATO bases because Russia wants nothing to do with Monsanto and Globalization.

  7. Look at the facts , 9.4 million tons of Round-Up have been sprayed since it’s invention in 74 worldwide . About 180 million pounds annually in USA , that figure might include Canada not sure. We sold out to Monsanto so long ago yet nobody realized it. When my parents came to Canada in the 50’s a hoe was used for weed control in the sugar beet fields , The first hoeing the beets were blocked out to a single plant and the weeds were hoed out , a tractor and cultivator was used between the rows , they were paid $14 a acre, between them they could hoe an acre a day, soybeans were grown in rows like corn and the soys were only cultivated with the tractor , the soys grew as tall as corn maybe 6 feet or more , once established they out competed weeds. Oats grew up to 6 feet tall too and we kids were told to go out and pull out the weeds , once the oats were going they simply out competed the weeds, Today’s varieties stand maybe two feet tall and just don’t compete well with weeds. Monsanto is invested in seed production for good reason, even if you don’t use GMO seed , the varieties aviable today are highly dependent on pesticides and fungicides to get a high crop yield. My last corn crop I used a recommended hybrid corn , but since I never replaced my pesticide license I had to cultivate my corn with no herbicide usage at all, in the center of the field I had used one bag of old fashioned open pollinated corn. I had to cultivate 4 times , on my third trip thru the corn field I noticed that the open pollinated corn was out competing the weeds compared to the hybrid corn. Come harvest time , the combine had a bushels to acre meter on it , we were quite surprised that the open pollinated yielded almost exactly the same, that was not expected.
    Today we have young people unemployed by the droves , we have the affluent going to the gym to keep fit . Nobody’s on the land, nobody has a hoe, the organic movement lobby to use more synthetic chemicals, more than the 10 they use now . Monsanto farm’s the farmers and now control the food production of the world . A few people have now awakened to that fact , some are concerned , most are not.

    1. “Monsanto farm’s the farmers and now control the food production of the world . A few people have now awakened to that fact , some are concerned , most are not.”

      This to me is the biggest problem. This takes away free choice. Always bad. No one entity or group should control the food production of the world. Many people don’t even understand where food comes from. Also, remember the ads “better living through chemistry”? Lies and propaganda.

    2. At my house, the weeds grow next to my vegetables and fruit plants and it is just a nuisance and it makes my garden look “ugly”. I pull out the weeds when I can but otherwise it has no effects on my plants because I fertilize well with organic matter. I also never spray any chemical on my plants and accept bug bite and so called “ugly” fruits. But the food industry has conditioned the consumer to like the perfect looking fruits and vegetables and so now they are busy spraying insecticides and pesticides in the quest of making nice looking but nutritionless and harmful produces.

  8. When did the governing authority come up with the idea in the first place that companies can sell any food substance to the public until someone (FDA) proves it unsafe instead of proving the safety of these artificial products for consumption on limited testing and or knowledge?

    1. It came about when the governing authority started getting money from the companies that produce and sell the food. And some of it is not even real food.

  9. I look at for nutritional info but just want to point out that poisoning the planet and other life, especially amphibians with RoundUp, is bad for our health in a RoundAbout way. Our individual health at each moment of our individual lives seems to take a lot of our attention. Along with our individual wealth. I don’t think that would disagree with that. I suppose I’m hinting that we need to always consider the health of the planet and the health of the future when we talk about health in any way shape or form.

      1. Thanks Thea but I think that Campbell, PCRM, Ornish etc all subsequently posted it on their blogs.

        Being In the Philippines/Australia .means I tend to see these things an hour or two before many people in the US.

  10. Well, at least we still have the option to buy organic and/or grow our own food. It’s too bad that organic at the grocery store is very expensive, though. I live on disability, but always buy organic when things are on sale or in season, for lower prices. And when, for example, organic strawberries are sky high, I just go without. I don’t want to eat GMO food, no matter how much money I don’t have.

  11. Why don’t they just use Phosphorus instead of glycophosphates? They could even use Sulfur. Sulfur improves productivity.

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  13. Now it has come to light that organic food can be sprayed with glyphosate, active Round up ingredient, and still be considederd organic. Unknowing consumers, like me, pay high prices for organic foods that are still killing them. Glyphosate accumulates in your body and causes more and more problems. These are some of the resources that I have used to educate myself. One even said that glyphosate combines with the genestein in soy to increase the glyphosate’s effect.
    Dr. Seneff

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