The topic of GMOs can bring up a lot of different responses and emotions. Many people don’t think about GMOs much, or just believe the conventional party line that they are safe and nothing to be concerned about. But anyone who thinks for themselves and looks into the issue generally gets all fired up.
I can see their point of view, but we need to approach GMOs with reason as well as emotion. The topic of GMOs is complex. There are many different ways that foods are genetically modified and different strategies have different potential health consequences. What is true for one kind of GMO may not be true for another. GMOs cannot be lumped all together as a single sound bite.
But, no matter their health consequences, we have a right to know what is in our food. GMOs should be clearly labeled, just as the protein, fat and carb contents ought to be clearly labeled. You have a right to choose what to put into your body. (Even in the current climate, you can still choose, if you are willing to do the research and shop and eat out in the right places.)
On one hand, if GMOs are as safe as Big Ag claims that they are, they ought to be able to convince us with clear, unbiased scientific studies. On the other hand, that Big Ag is so actively involved in controlling what studies get done and what studies get published, cutting off the funding for any institution that does not do their bidding, putting their executives on the boards of scientific journals and forcing the retractions of damaging studies that have been published, spending millions of dollars fighting state GMO labeling initiatives, and other such behaviors just raises the suspicions of those of us who are skeptical that we are being told the truth about GMOs.
But, like I said, GMOs are a mixed bag. For example, the first genetically engineered food product approved by the FDA in 1990 was a form of E. coli engineered to make the enzyme chymosin, which promotes the ripening of cheese. Roughly 80% of hard cheeses sold in the US are made using chymosin from these E. coli. But this is the same technology that is used to train E. coli to make human insulin. The vast majority of the insulin now used in the US comes from genetically engineered E. coli. Does using a genetically engineered enzyme in the production of cheese make the cheese more harmful to you? I would find that difficult to believe.
On the other hand, one strategy used to make corn less susceptible to soft-bodied caterpillars is to genetically engineer the corn to make Bt toxin within its tissues, so that when the caterpillar eats the corn, it dies. Bt toxin is thought to be safe for humans. In fact, farmers can spray the bacteria that make Bt toxin on their plants and still meet government criteria for being organic.
But there are two problems I see with eating corn impregnated with Bt toxin. First, Bt toxin kills the caterpillars by increasing the permeability of the membrane lining their intestines. Increased intestinal permeability is called “leaky gut syndrome” in people. It eventually leads to body-wide inflammation and the development of food allergies and auto-immune diseases. Bt toxin, by itself, probably does not cause leaky gut in humans, but it has recently been discovered that Bt toxin binds with a protein commonly found in mammalian intestines and the Bt-protein complex causes leaky gut. (http://www.gmofreeusa.org/wp-content/uploads/2014/11/2011_11_JAT_CytotoxicityOnHumanCellsOfCry1AbAndCry1AcBt.pdf) Since conventional medicine ignores food allergies and leaky gut, these influences would not be noticed in any food toxicity studies. The rate of auto-immune diseases in the US has skyrocketed since the introduction of Bt corn in the US. (Just a correlation, so far, not a proven causation.)
The second problem is that a bacterium that causes tumors in plants, Agrobacterium tumefaciens, can transfer genes into plant and human cells. It is used in genetic engineering. It is a natural bacterium in soil and in your intestines. It can move the gene that makes Bt toxin from the corn you eat to the friendly bacteria in your intestines, turning your own microbiome into a pesticide-producing factory (http://www.huffingtonpost.com/dr-mercola/bt-corn_b_2442072.html). Once your own friendly bacteria start making Bt toxin, how do you get them out? This may be one more cause of leaky gut syndrome and, thus, chronic inflammation.
Also, glyphosate, the active ingredient in Round Up®, was first patented as an antibiotic. It kills the bacteria in the soil and in your gut. Very little is yet known about the microbiome of the soil and your intestines so, again, adverse reactions to altering these things would likely be missed in toxicology studies. Yet, all of your physical health starts with the health of the soil. And the more we learn about your gut microbiome, the more important it looks. Eating foods with glyphosate residues and spraying glyphosate-containing compounds around your yard are very likely detrimental to your health and the health of everyone else.
There are many more details about the health effects of foods with different GMO strategies, I just presented a couple for illustration.
So, some strategies for genetic engineering are probably safe and other are probably not. It is not accurate, nor wise, to lump all GMOs into one category. What is clear is that GMOs are here to stay. So we really need to get politics and corporate profits out of the way of good, unbiased science and take a clear, honest look at what we are doing to ourselves and the planet with this technology.