This past week I read the full text of a new groundbreaking study on GMO’s. It simultaneously sunk my heart and sparked me up.  For the first time since the early 1990’s when GMO’s were introduced into our food supply, we have definitive proof that GMO’s pose a serious and fatal health threat.   Eating GMO corn and the herbicide Roundup at levels currently considered “safe” can cause cancerous breast tumors and multiple organ damage (liver and kidney) and can also lead to premature death in laboratory animals.

The study, led by molecular biologist Gilles-Eric Seralini of the University of Caen in France, was published this month in the prestigious peer-reviewed journal Food and Chemical Toxicology.  After reading this article, you may also want to view this short video that was filmed during the study to help you get the full impact of the significance of its findings.· Click on the image above to view it.

Monsanto’s GMO corn, called NK603, has been engineered to be resistant to Roundup.  This allows farmers to douse fields with massive amounts of Roundup without worrying about killing the corn.  No long-term studies have ever been conducted to determine whether it would kill animals or humans.  Many researchers have previously warned that the GMO corn, sprayed with Roundup or not, is unsafe to eat, and this new study shows they’ve been right all along.  In the groups exposed to the GMO’s and Roundup, both separately and combined, there was a 600 percent increase—or six times more deaths—compared to the control group!

The problem here for all of us is that GMO corn is used to make literally hundreds of foods and food additives.  It shows up in 70 percent of processed or packaged food in U.S. grocery stores.  Some of the common sources of GMO corn are: ascorbic acid, Aspartame, Nutrasweet, baking powder, citric acid, cornstarch, modified food starch, erythritol, xylitol, fructose (any form), maltodextrin, monosodium glutamate,  xanthan gum, and the endless number of corn products such as breakfast cereals, tortilla chips, corn tortillas, corn flour, corn masa, corn oil, high fructose corn syrup, and corn syrup, just to name a few.

The results of this study make it even more imperative to avoid GMO sources of corn by consuming only organic corn products.  By USDA law, organic crops cannot come from GMO seeds.  Eating a processed-free diet also makes it easier to avoid GMO’s. And just to let you know, all of the ingredients in Dee’s Naturals products are non-GMO, including the baking powder.  Most baking powders contain cornstarch, and since there are no GMO labeling laws in the United States, we have no way of knowing if the corn used to make the cornstarch was from GMO corn.  If you want a non-GMO baking powder to use in your home baking, Bob’s Red Mill is a trusted brand.

Now, back to the study.  There were several significant and unique aspects of this study that set it apart from all other research on GMO’s to date:

  • It is the only independent study ever conducted on GMO’s, so there were no conflicts of interest.  This research was conducted by a non-governmental organization in France.  All previous studies have been carried out by Monsanto, the huge agri-giant corporation which owns the patent on the GMO seeds and on the weedkiller Roundup.
  • It is the only long-term animal feeding trial, conducted over two years (the average lifespan of a rat.)  Previously, industry-funded studies have determined that GMO crops are safe to eat, but they were much shorter term, consisting only of 90-day feeding trials.  Opponents of GMO foods have criticized earlier research for being so short-term that it misses any chronic health problems that would be caused from ingesting GMO food long-term.  This new research is significant because it found that even consuming low levels of GMO corn and Roundup, separately or combined, can cause serious health problems in rats that only became apparent after they were older than 90 days. The first tumor was observed after 120 days, but the majority were only detected after 18 months. This would be equivalent to 13-22 years of age in a human eating GMO food and Roundup sprayed food since birth. So far we have not gotten this far along in our unintentional “human large scale experiment.”  This fact alone is what sunk my heart.
  • They used the actual formulation of Roundup that is sprayed on GMO crops. All other research has only studied the effect of the active ingredient in Roundup called glyphosate. In those studies, according to Monsanto, glyphosate alone is not harmful.  However, it is important to note that glyphosate is only able to efficiently penetrate target plant organisms with the help of other compounds present in the Roundup formulations.  When Roundup residues are found in tap water, food, or animal feed, they are from the total Roundup formulation, which is the most commonly used mixture in agriculture. So these researchers used the actual Roundup formulation available on the market, not just glyphosate, so that their study would mimic what people actually get in their food or what has been found in tap water, to study its health effects.
  • They studied the effect of consuming GMO corn alone, GMO corn sprayed with Roundup, and Roundup alone.  No other studies have been this extensive in determining the singular and synergistic effects of GMO corn and Roundup.

Here’s a summary of how the study was conducted (click here to read the study in its entirety):

The Rats:

  • The study was carried out using 200 rats fed a standard balanced diet. They were divided into ten groups, each containing ten males and ten females.
  • One group (the control group) was fed a diet containing 33% of non-GMO corn and plain drinking water.
  • Three groups tested the effect of GMO corn alone. Each group had a different proportion of GMO corn in their feed starting at 11%, then 22% and finally 33% of their total diet.
  • Three groups tested the effect of GMO corn which had been sprayed with Roundup in the field at the same proportions of 11%, 22 % and 33% of their total diet.
  • Three groups were fed the same diet as the control group (33% non-GMO corn) but were given Roundup in their drinking water in order to test for Roundup alone.  The Roundup was administered at three different concentrations with one control group:
  1. The lowest level contained 1.1 x 10-8 % of Roundup, an amount that corresponds to typical contamination found in some tap water (according to the study authors).
  2. The intermediate level contained .09%, which is half of the US MRL (maximum residue limit) of glyphosate permitted in GMO animal feed.
  3. The highest level was .5%, which is half of the strength of Roundup when diluted for use in agriculture.

The researchers took blood and urine samples for analysis monthly for the first three months and then every three months and at the end of the trial studied the rats’ principal organs.

The Corn:

The type of GMO corn fed to the rats is known as NK603. This is a Roundup-tolerant variety of corn owned by Monsanto (according to the film, the researchers had to secretly purchase the GMO corn from a source in Canada, as Monanto does not allow the corn to be purchased without a contract, and they don’t allow it to be used for research by any organization other than themselves).

The control group was fed the nearest isogenic, non-GMO corn. (So basically they compared Monsanto’s GMO corn to a non-GMO corn that has similar DNA structure. (Monsanto claims their GMO corn is theoretically genetically identical to non-GMO corn and they claim they should not have to study long term effects of their GMO corn for this reason.)

They studied both the GMO corn grown in a field by itself with no Roundup applied as well as the GMO corn which had Roundup applied to it. They were careful to grow the non-GMO corn, the GMO corn and the GMO corn with Roundup applied in similar fields and conditions.

The Findings:

It is important to remember that this was a two year experiment. Most lab rats live about two years, so this experiment followed these animals through what a normal life-span would be for them.

In the study article, there is a detailed summary table (Table 2) that you can take a look at. It gives you a quick comparison of the most frequent health effects caused by the GMO corn and GMO corn with Roundup and Roundup in water. The interesting thing that you notice right off is that indeed the GMO corn and GMOcorn/Roundup and Roundup water groups always have more health problems than the controls.

  • 50 percent of male rats and 70 percent of female rats fed Monsanto’s GMO corn and Roundup died prematurely, compared to only 30 percent and 20 percent in the control group.
  • The largest palpable growths were found to be non-regressive tumors. Tumors were found to increase in size and number over the course of the experiment. The tumors were usually 2-3 times more likely in the treated groups than controls. This was in both females and males.
  • In females the largest tumors were in total 5 times more frequent than in males after the 2 year period. 93% of them were mammary (breast) tumors. (Hmmm, anyone making a connection to the increase of breast cancer in human females?)
  • At the end of the two years 50-80% of the treated female animals had developed tumors while only 30% of the controls were affected.
  • The Roundup treatment groups showed the greatest rates of tumor incidence with 80% of the animals affected. These breast tumors are generally known to be mostly estrogen-dependent (Roundup has been shown to disrupt natural compounds in the body which synthesize estrogens as well as interfere with estrogen and androgen receptors in cells).
  • The second most affected organ in the females was the pituitary gland. They were affected 2 times more than the controls for most treatments (The pituitary gland is very important as it regulates many hormonal systems of the body).
  • The largest palpable tumors in the males (in their kidneys and skin mostly) were by the end of the two years on average seen twice as often as the controls.
  • The most affected organs in the male rats were the liver, digestive tract and kidneys. Liver congestion and both visible and microscopic areas of dead liver tissue were 2.5-5.5 times more frequent in all the treatment groups than the control groups.
  • The males at the highest Roundup treatment  had almost double the usual amount of estrogen.  (Hmmm..anyone seeing a connection to men eating GMO food that are using Viagra or some other erectile enhancer?)  This one brought to my mind all the farmers reporting poor fertility in their animals they’ve been feeding GMO corn feed.  Could this also correlate to the huge increase in human infertility?

My Thoughts:

One other significant thing to note is that the groups with smaller amounts of GMO corn, GMO corn with Roundup and Roundup water caused as much damage as the groups who consumed or drank larger amounts. And even the group that had no GMO corn, and was only exposed to the Roundup in the water, developed tumors.  What sank my heart about this study was the realization that people, especially children, who are ingesting as much as 11% of their diet as GMO food could be causing themselves as much organ damage and growing as many tumors as those  eating 33% of their diet as GMO food. That’s horrifying!

I’ve written before about GMO’s, and I’ll keep writing about them until we finally see some legislation in this country.  It’s been disheartening to learn that in general, a 90-day animal study is all Monsanto has had to provide to win approval of any of their genetically modified crops.

I do want to point out that criticisms have quickly emerged, suggesting insufficient sample sizes, a breed of rats prone to tumor growth, and a lead researcher who was seemingly already convinced of the dangers of GMOs. One of the critics, Charles Benbrook of the Center for Sustaining Agriculture and Natural Resources at Washington State University, also pointed out “On the other hand, the study is actually more carefully designed and has the same sample size as the original study conducted on behalf of Monsanto and submitted to regulatory agencies in support of the approval of the tech in the first place. If industry thought that study had a good design, it’s a little disingenuous of them to be criticizing this study.

He is quoted in The Huffington Post as saying “I do think that this new study again raises an alarm bell, and ought to be followed up by much more careful studies with larger sample sizes, more than one species of lab animal and conducted by people that have no dogma on the side, haven’t done research in the area and don’t have an opinion in the area.”  Benbrook has also warned about the increased use of pesticides that has come with the explosive growth of GMO crops designed to be resistant to the chemicals.

It may sound exaggerated, but genetically modified foods are, from my perception, one of the most significant health threats of our time.  This study has proven that.  We are living in a food experiment and we are all the laboratory rats.  Please do all you can to avoid GMO’s.

If you want to learn more about GMO’s and how to avoid them, you can read my previous article, The Most Important Food Fight of Our Time, and my  three-part article on GMOs Just Say No to GMO’s part 1part 2, and part 3.


Gilles-Eric Séralini, Emilie Clair, Robin Mesnage, et. al., “Long term toxicity of a Roundup herbicide and a Roundup-tolerant genetically modified maize, ” Food and Chemical Toxicology

Sewell, Anne, “Results of first animal feeding trial on GM maize & Roundup,” Digital Journal (accessed September 25, 2012).

Peeples, Lynn, “GMO Debate Heats Up: Critics Say Biotech Industry Manipulating Genes, And Science,” Huffington Post (accessed September 25, 2012).