If you covered your ears, when you read the headline, I wouldn't really blame you. Isn't it enough to have to worry about gluten (and for many of us, dairy)? Do we really have to restrict our diets further? Well I don’t meant to scare you with a seemingly sensationalistic subject, but just like the CSI guys, I do follow the evidence. And so what I have to say now is really important information. I hope you stopped in your tracks to read this.
Last week at the Gluten Summit, there were so many astounding interviews, and I'll probably be bringing up a few of the more moving topics over the next few weeks. But the most astounding of all was the discussion on GMOs by Jeffery Smith. I've always had a ‘gut feeling’ that GMOs might be problematic, and have avoided them for my family. After all, the rise in food allergies, gluten sensitivities and autoimmune disorders does have amazing coincidence with the timing of the introduction of GMOs in our food system (starting in 1996). But I’ve never really discussed them here, mostly due to the lack of scientific evidence supporting any claims that they are “bad.” And perhaps, thinking the discussion might be a little off-topic. Until now. Recent studies have come to light that genetically modified foods ARE bad for us. And those of us with gluten sensitivities should be concerned.
Genetically modified corn, which comprises most of the corn consumed in the US, can cause intestinal permeability. Just like gluten. Let me say it again. GMO corn causes leaky gut.
In case you are not familiar with the term, intestinal permeability (aka ‘leaky gut’) is when the lining of the intestine develops holes in it, allowing tiny particles of undigested food, toxins, microbes, etc. to leak through the intestinal wall. From there, these particles enter the bloodstream, and can even cross the blood-brain barrier,  prompting an immune reaction and leading to a whole host of diseases and complications, from celiac disease and increased food allergies, to Chron’s disease and possibly even autism and some cancers. Gluten is known to cause leaky gut for celiacs, which is why celiac disease patients often have other associated diseases.
So how does GMO corn cause intestinal permeability? Large scale crops, such as corn, have been genetically engineered to contain a “natural” pesticide, known as Bacillus thuringiensis, or “Bt” for short. You might also hear this GMO corn referred to as Bt corn. This pesticide is actually a bacteria genetically modified from the naturally occurring Bt, and placed into the DNA of the corn, where it is expressed in every part of the corn. Bt attacks the intestinal lining of bugs eating the corn (the corn borer being the targeted insect), and through the after-effects of intestinal permeability, the predator eventually dies. This is the same disease pathway that affects us humans, if we don't get our leaky guts under control.
So why should we be concerned about the poor corn borer consuming Bt? Well first of all, Bt is not selective in who it kills, so if a butterfly or a bee ingests it, guess what. They will die, too. ,  Have you heard? Our monarchs and our honeybees are on their way to becoming endangered species! Are GMO crops to blame? That heart-breaking discussion we’ll have to save for another day.
Back to you and I, and our delicate gut ecosystem. As it turns out, Bt remains in the corn even after we, humans, ingest it. AND it remains alive even as it enters our digestive tract. If left unchecked, it can continue to live in our digestive tract, and if we continue to eat Bt corn, it will continue to thrive. 
So? Is it really harmful to us? Monsanto (and other Big-Ag industry leaders) as well as the FDA would have you believe that there is no problem with Bt corn for human consumption, because (they say) Bt never interacts with humans or mammals. No study on the potential effects on humans was ever done before they unleashed GMOs in our fields and our produce aisles. Why not? Because FDA is in bed with the biotech industry. This is not sensationalistic, conspiracy-theory minded hearsay. Know who just so happens to be the Deputy Commissioner for Foods at FDA? Former Vice President for Public Policy at Monsanto, Michael Taylor! He also was once a lawyer for Monsanto earlier in his career. Things that make you go, hmmm.
In 2008, however, several studies were published showing “serious health risks associated with GM food consumption” by mice and rats, “including infertility, immune dysregulations, accelerated aging, …insulin regulation, …and changes in the liver, kidney, spleen and gastrointestinal system.” These are pretty serious allegations. But we’re just talking about rodents, right? What about humans? Finally in 2012, another study applied the Bt corn toxin to human cells and do you know what happened? Bt corn poked holes in the human cells causing leakage! The Bt toxin has been found in human blood and, scariest of all, in cord blood of unborn fetuses! This means it could reach the brain, and, as Mr. Smith alluded to, could offer a possible explanation for the rising epidemic of autism.
This same study also looked at the effects of Roundup (glycophosate) on humans. See, GMO crops are also genetically engineered to be able to withstand the herbicide, Roundup, so that fields can be sprayed with a crop duster, killing all weeds, but never harming the corn that will soon make its way to our dinner plate. Is it any surprise that this study found that Roundup, even in small doses, is also toxic to humans? Mr. Smith went into a lot of discussion about this, stating that Roundup kills the beneficial bacteria but doesn’t kill E. coli, Salmonella, and botulism, thereby resulting in gut “dysbiosis” leading to (once again) leaky gut, as well as inflammation. As we’ve already discussed, these are conditions that can lead to (once again) autoimmune disorders, increased food allergies, and even autism and cancer. Sweet corn doesn’t look so sweet, now, does it?
So as it turns out, GMO corn is just as bad for us as gluten! Especially, if you are trying to heal an already leaky gut. And so is soy! Well (unfermented) soy is bad for a variety of other reasons, too. So please don’t eat it, ever! And most corn and soy in the US are GMO, and are sprayed with Roundup, too. Know what else is GMO? Refined sugar from sugar beets, and potatoes. Know what else is sprayed with glycophosate? Most grains before being harvested (wheat, rye and barley), as well as lentils, citrus and sweet potatoes.
Maybe this explains why many people feel better after adopting a paleo diet. Most of these GMO foods are, by default, eliminated in the paleo diet. In fact, Mr. Smith goes on to tell of doctors who have prescribed a non-GMO diet to their patients and have found that their symptoms of IBD/IBS, constipation/diarrhea , bloating and gas, gut pain, and even Crohn’s went away!
So what should you do? If you can't give up your corn tortillas, please only consume organic corn, as that is the only corn that is not GMO. In fact, if a food is labeled as organic, it should be non-GMO. You can also look for the “Non-GMO Project” verified labels. You can find out which other foods are genetically modified and download a shopping list at nongmoshoppingguide.com.
Also, you may want to get politically involved. A number of states are working on passing legislation to make food manufacturers label any foods that contain GMOs. In fact, just last week, Kauai County Council allowed a bill to pass which will force companies to disclose what GMO crops are being grown on Kauai. Go, Hawaii! Its hard to know why similar bills were shot down in Washington state this year and California last year. Might we surmise that Monsanto’s power is that far-reaching…?
 Catassi, C. et al. Non-Celiac Gluten Sensitivity: The New Frontier of Gluten Related Disorders. Nutrients 2013, 5, 3839-3853.
Perason, ADJ, et al. Intestinal permeability in children with Crohn's disease and coeliac disease. British Medical Journal Volume 285 3 July 1982.
 Catassi, C. et al. 2013.
Thomas Jefferson University (2012, February 21). Stronger intestinal barrier may prevent cancer in the rest of the body, new study suggests. http://www.sciencedaily.com/releases/2012/02/120221212345.htm
 University of Nebraska Plant & Soil Sciences eLibrary. European Corn Borer and Bacillus thuringiensis. How Bt Kills European Corn Borer. http://passel.unl.edu/pages/informationmodule.php?idinformationmodule=994877762&topicorder=6&maxto=11
Losey, JE. Transgenic pollen harms monarch larvae. Nature. 1999 May 20;399(6733):214.
Ramirez-Romero R, Desneux N, Decourtyec A, Chaffiol A, Pham-Delegue MH. Does Cry1Ab protein affect learning performances of the honey bee Apis mellifera L. (Hymenoptera, Apidae)? Ecotoxicol Environ Saf. 2008;70:327–333. doi: 10.1016/j.ecoenv.2007.12.002.
Mesnage R. et al. Cytotoxicity on human cells of Cry1Ab and Cry1Ac Bt insecticidal toxins alone or with a glyphosate-based herbicide. Journal of Applied Toxicology. Vol 33 Issue 7. Pages 695-699. July 2013.
American Academy of Environmental Medicine. Genetically Modified Foods Position Paper. 2009. http://www.aaemonline.org/gmopost.html
Mesnage et al. 2013.