PHOTO: iStock/Thinkstock
Lisa Munniksma
May 24, 2016

I was in college when genetically modified crops were introduced. I was getting an ag degree (not sustainable ag—those didn’t exist then), and I fully bought in to the idea that GMOs were going to feed the world. Higher yields, fewer inputs, drought and pest resistance—they were a miracle of modern science!

Fast-forward 10 years, I was living in industrial-farming country, and a crop-duster plane flew low over my farm while I was riding my horse, set to spray the farm next door. I started thinking about the chemical that was in that plane, the crops it was going to treat and my life in the middle of this landscape. That was the beginning of my path toward GM-crop skepticism.

It’s now been 20 years since GMOs have been introduced to the marketplace, and 94 percent of cotton, 93 percent of corn and 94 percent of soybeans planted in the U.S. are genetically modified. Last week, the National Academy of Sciences released a report about the safety of GMOs and how the promises made by GM-seed manufacturers have held up. This report pulls together data from studies done since the beginning of GM seeds and questions and comments from the public regarding the potential effects of GMOs, and it’s fascinating.

As someone who isn’t completely anti-GMO but who is against the environmental damage that’s caused by GMOs, there are parts of this report that are hard to read because they don’t fit into what I have come to believe. There are also parts that sing exactly what I’ve been saying all along. Either way, it’s good for me—for us—to read a summary of 20-plus years of GMO data evaluation. In case you don’t want to read the whole 407-page report, here are six things you may have been told or believed about GMOs that the NAS says are wrong.

Myth 1: GM Crops Have Higher Yields

NAS says: The researchers found that crop yields have increased since the introduction of GM seeds, but they can’t pin that finding on the GM crops themselves. Conventional plant-breeding techniques have been improving during the past 20 years, as well, and there’s no evidence to say that it’s the genetic modifications rather than the improved plant breeding that have caused the yield bump.

Myth 2: GM Crops Are Responsible For A Lack Of Crop Rotation & Diversity

NAS says: The NAS report says crop rotation and crop diversity has declined in the Midwest U.S., but it could be because commodity-crop prices dictate planting decisions rather than because of the availability of or pressure to plant GM seeds. The report also says the number of crop varieties in use around the world has declined significantly in the past century, but much of this loss of biodiversity took place before GM seeds were available.

Myth 3: Bt In GM Crops Has Reduced Insect Biodiversity

NAS says: NAS’s review of research actually found that GM crops with a Bacillus thuringiensis trait resulted in higher insect biodiversity than crops that are sprayed with a pesticide. The use of Bt crops has resulted in regional declines in pest-insect species. Also, the use of Bt crops has reduced the spraying of pesticides on those fields.

Myth 4: GM Crops Allow For Increased No-till Planting, Thus Reducing Erosion & Improving Soil Tilth

NAS says: While no-till and reduced-till practices have increased over the past 20 years, researchers found no direct correlation between the introduction of GM crops and no-till’s increase.

Myth 5: Livestock Fed GM Grains Aren’t As Healthy

NAS says: NAS researchers looked at experimental data and long-term data on the health and feed conversion of livestock from before and after the introduction of GM feed and found no overall difference.

Myth 6: GM Foods Cause Autism In Children

NAS says: The patterns of children with autism spectrum disorder is too similar in the U.S. and United Kingdom to pin the fault on GMOs. (In the U.S., GMOs are a common part of the diet; in the U.K., they are not.)

The findings go on for hundreds of pages, addressing some very common questions about and objections to GM crops. Reading this whole report is probably unreasonable, but you might look at the summary of findings to pick out and read about other issues that are most important to you.


Next Up