GMOs are very controversial for two reasons. Firstly, there is a lot of misinformation out there and secondly GMOs are not well understood by the general public. Rather than discuss the topic in detail I have decided to focus on some of the common myths. I will present a number of GMO myths and if the reader is interested in more detail they can look at the references.
If you have formed an opinion on GMOs based what you have read on popular web sites and in newspapers, you have probably reached the wrong conclusion. The anti-GMO movement is strong and based almost entirely on emotion and fear. Science does not back up most of their claims.

What is a GMO?
It always amazes me that people form opinions and have strong views on topics without ever taking the time to understand the basic facts. I’ll bet that less than 1% of people, with an opinion about GMO either for or against, actually know what a GMO is. For quite some time I was one of the 99% that thought they knew what a GMO was – I was wrong.
GMO stands for Genetically Modified Organism. In its simplest terms any organism that has had its DNA changed is a GMO. Based on this definition all of the fruits and vegetables you eat are GMOs. We seldom eat native fruits and vegetables that have not been bred to make the food better.
The above definition is not very helpful so people redefining the term. A plant GMO was redefined as a process that a) takes place in a lab, and b) has DNA from a different type of organism (ie not a plant) placed into the DNA of plants. For example, some fish genes were moved into Christmas trees, which then glowed. These are a GMO plant.
This last definition seems to be the one that is used by most people.
What is the Real Definition of GMO?
What about a lab procedure that adds DNA from one plant into another plant – other types of organisms are not involved? Is that a GMO? Some might say yes since it was done in the lab. But what if plant species A is pollinated by plant species B and the offspring have new DNA genes? Is there really any difference just because it was done in a lab? Not really.
There is a French wheat called Renan which was produced by breeders who bathed wheat and two other species of plants in a carcinogen, colchicine, which affects the way chromosomes connect to each other. They then exposed them to X-rays to further alter the DNA. This produced a very disease resistant wheat containing DNA from all three species and it was clearly produced in the lab. It has been grown in Europe for years but it is not a GMO according to the EU because it did not use the gene transfer technology called transgenesis, that has been used for modern day gene manipulation. So being done in a lab is not an important part of the definition.
Consider the sweet potato. When scientists studied the DNA of the sweet potato they found that it contained DNA from a bacteria called Agrobacterium. This DNA has been there for thousands of years. Agrobacterium uses a method of transferring its DNA into other species that is very similar to the method used to make GMOs. The sweet potato is a natural GMO, produced by nature. It has DNA from both plants and bacteria. Should the sweet potato be called a GMO?

Monsanto developed Roundup-resistant seed by transferring DNA from Agrobacteria into plants. Sounds very similar to how nature made the sweet potato?
The last couple of examples show why the previous definition of GMO are not correct. A GMO may or may not have been made in the lab – nature can make GMOs all on her own. A GMO may or may not have DNA from a different type of organism.
It is very difficult to find a suitable definition for GMO. In some ways GMO is a lab procedure, transgenesis, and when this technique is used the resulting organism is a GMO organism. But we now have new and improved procedures like gene silencing, mutagenesis, and CRISPR. Should plants produced by these new procedures also be called GMO? Right now they are not GMOs and they are not controlled by GMO laws and regulations. For a more in-depth discussion about the definition of GMO have a look at . ‘s article on Grist
I find it both amusing and concerning that people have such strong views about something that is not well defined!
Gardeners Can Not Buy GMO Seed
I see comments about this all the time. Gardeners are concerned that they will get GMO seed when they buy a package of seed. This completely unfounded fear has caused most seed companies to stamp their websites and catalogs in big letters; ‘NO GMO’.
The whole thing is stupid. The only way to buy GMO seed is to sign a contract with the supplier of the seed. They won’t do that for a $3 package of seed.
Besides, only a few types of seeds are available as GMO. Common things like carrots and beans are not available as GMO seed even to farmers.
UPDATE 2024: Gardeners in the USA now have access to three GMO seeds. One is the “firefly petunia” which emits a continuous green glow thanks to genes from a mushroom. The other is the tomato ‘Purple’ and the third is the UH Rainbow papaya which is only available in Hawaii.
Our Food is Not Natural
One of the misconceptions is that all of our food is produced by natural pollination, or by a human moving pollen from one plant to another, which mimics the “natural way”. This is seen as much better than “lab manipulation.
The reality is that many of today’s cultivars were and are still produced by exposing seeds to harmful X-rays (Radiation Mutation Breeding) and carcinogens. These techniques scramble the DNA and produce new kinds of plants. “The Mutant Variety Database, which collects information on plant varieties created through radiation breeding and other similar ‘mutation breeding’ techniques, logs over 3,000 improved varieties, including grapefruit, rice, wheat and barley. In Vietnam, around half the soya beans planted are mutant varieties.” Rice, wheat, barley, pears, peas, cotton, peppermint, sunflowers, peanuts, grapefruit, sesame, bananas, cassava, and sorghum are just some of the mutant foods we eat today.
The cultivars produced this way are not GMOs, but is there really any difference? If you understand the technologies you would be much more concerned about mutation breeding than GMO.
Since these are not GMO seeds they can be sold almost anywhere in the world including Europe. I suspect that some of these seeds are sold to gardeners in small seed packages.
Organic Gardeners ARE Allowed to Use Genetically Modified Seed
Organic farmers are not allowed to use GMO seed, but they can certainly use genetically modified seed as well as seed produced by mutagenesis.
At the moment they are also allowed to use seed produced by the other newer gene modification procedures. This may change in time.
Organic gardeners growing sweet potatoes are growing a GMO and that is quite acceptable.
Farmers Are Not Harmed by GMO
There are numerous myths about the harm that GMO is doing to farmers, including the following:
- Farmers are forced to buy GMO. Farmers have been buying seeds long before the introduction of GMO seed. Before GMOs, 90% of all seeds planted in developed countries were hybrids, and most were patented and owned by seed companies. GMOs did not change the rules for replanting seed.
- Farmers want to save seed. This is not the case. Saving seed is too much work and it’s too expensive.
- Farmers are forced to buy GMO seed. That is not true. There are many other options. They buy GMO because it is more profitable than other options. GMO crops can also reduce pesticide use making farming safer.
If you really believe these myths, talk to a farmer.
GMO Food is Safe to Eat
Note added Jan 2025: A review was recently published by Richard E. Goodman called Twenty-eight years of GM Food and feed without harm: why not accept them? In it he reviews the evidence for harm caused by GMO food. He concludes “No new GMO has been proven to be a hazard or cause harm to human consumers”.
There is absolutely no scientific evidence that GMO food is unsafe to eat. There has been some research done showing GMO food causes tumors in rats, but that research has been completely debunked. The author, Gilles-Eric Séralini, was forced to withdraw the work due to poor experiment design and a refusal to release data. But the anti-GMO movement still presents it as fact. It’s not.
Consider this for a moment. The procedure used to make a GMO, transgenesis, moves a couple of very specific genes from one organism to another. The process is very controlled, the scientists know exactly which genes are being moved and the DNA in the resulting organism is well tested.
Compare that to natural plant breeding where you mix and shake thousands of genes and have no idea what is in the new organism. This is considered to be perfectly safe to eat. In mutagenesis the radiation scrambles the DNA and we have no idea what it has done to the genes. In fact the damage is so great that most treated seeds don’t even develop properly – their DNA is so damaged that they can’t grow. We consider this food to be perfectly safe to eat.
GMO food is well tested. Natural genetics and mutagenesis undergo almost no testing.
I have no problem with people being against genetically modified food, but the reason for this fear should not be based on food safety. GMO food is perfectly safe.
Naturally Produced Plants May Not be Safe to Eat
Most people think that natural breeding and selection produces completely safe foods. Farmers have been doing this for hundreds of years – how can this cause a problem?
Naturally bred potatoes, called Lenape, had to be taken off the market because they contained toxic levels of alpha-solanine and alpha-chaconine, which are human plasma cholinesterase inhibitors. These are not sprayed pesticides. Alpha-solanine and alpha-chaconine are natural pesticides produced by all varieties of potatoes – they are in every French fry you eat, even the organic ones. Selective breeding just increased the amounts to toxic levels.
RC Beier, in a recent study reported that “A new celery cultivar (a result of plant breeding to produce a more pest-resistant variety) was responsible for significant incidences of phytophotodermatitis (inflammatory eruption resulting from contact with light-sensitizing botanical substances) of grocery employees.” Natural breeding produced a variety of celery that caused blistering and rashes on the skin.
Natural breeding is not any safer than genetic engineering. Each method can produce food that is toxic to us. Each plant produced should be properly tested. But new cultivars produced by natural breeding get no testing at all – until you eat it.
GMOs are All About Roundup
A phrase such as, ‘I am against GMOs because I don’t want Roundup to be used” is very common. People associate GMO and Roundup, but that is mostly a false association and shows a lack of understanding about GMO.
It is true that Monsanto developed Roundup and they developed some of the first GMOs. It is also true that Monsanto developed GMO corn and soybean that is ‘Roundup Ready’. This means that growing plants can be sprayed with Roundup and it won’t kill the crop plants.
However, most GMO plants have nothing to do with Roundup. Most GMO plants are not Roundup Ready and most are not produced by Monsanto.
The majority of GMO plants have been developed to reduce the effects of pests and disease.
Non-GMO Herbicide Ready Seeds
Selling Roundup Ready seeds is a big business. Why? Because it adds a lot of profit for both the farmer and the seed company. Europe banned GMO seed and therefore farmers in Europe can not buy such seed.
Not a problem. Companies soon developed herbicide-resistant seeds using mutagenesis. These work just as well as GMO seeds, they are developed in a lab, they have not been as closely tested as the GMO seed, but they are not banned in countries that have banned GMO seeds. Even organic farmers can use them.
As an example, Clearfield is a variety of canola that is herbicide resistant but it is not a GMO.
The point here is that Roundup and GMO really have nothing to do with each other. They are different topics and risks and fears associated with them should be discussed separately.
GMOs Increase Herbicide Use
Andrew Kniss looked at the relative toxicity of herbicide use in the US from 1990 to 2015. He found that herbicide use increased on genetically engineered glyphosate-resistant corn, cotton, rice, and wheat. But the increase in non genetically engineered rice and wheat increased at a faster pace.
The use of GMOs is actually reducing the rate at which herbicides are used.
More importantly, GMOs are also reducing the toxicity of the herbicides used. Farmers using GMO seeds are able to use Roundup instead of the more toxic herbicides they used to use.
Many reports look at the weight of pesticides used and try to do comparisons, but this is mostly a silly, pointless exercise because they ignore the toxicity of the product being used. Consider this simple example. Assume only two pesticides are used. Pesticide A is 100 times more toxic than pesticide B. If I report that total pesticide use has gone up in terms of weight – what does that tell you? Not much. If the total weight has gone up, but the amount of A is down, the situation is much better for the environment.
From a herbicide point of view, GMOs are reducing the environmental impact of herbicide use.
Insect Resistant GMOs Reduce Insecticide Use
As stated above most GMOs have nothing to do with Roundup. Most have been developed to create plants that produce more natural insecticides. Plants produce hundreds of natural pesticides to keep pests from eating them. By genetically altering the DNA, plants can be created that produce more insecticide than normal. If they produce more insecticide, farmers need to spray less often.
This is precisely what Monsanto has done. They developed a soybean called Intacta which requires far less spraying. Jack Kaskey reports that “Soybean growers in northern Brazil who normally make six to 10 insecticide applications a season require only one or two sprays with Intacta crops. “.
The reduction in insecticide use has been so dramatic that “DuPont said it won’t restart a Texas factory that makes Lannate insecticide partly because insect resistant crops ( ie GM crops) have eroded sales”.
If you are anti-GMO, you are also for increased pesticide use!
What about Superweeds?
Spraying a lot of Roundup does produce super weeds which are weeds that have become resistant to Roundup.
Many people think that the reason for such weeds is that the GMO Roundup Ready crops are cross-pollinating with weeds, which in turn produce GMO weed offspring. That is not very likely with most crops since the crops and weeds are too genetically different to breed. There is a slight chance this might happen with oilseed rape and sugar beet.
Superweeds are produced the old-fashioned way. A genetic mutation occurs in a single plant that makes it Roundup-resistant. It then survives a spraying event and passes on its genes to future offspring. This type of natural selection has been documented well before the introduction of GMOs.
An increased use of GMOs has resulted in increased Roundup use, and this could lead to more superweeds.
But this is a problem with the use of Roundup, not with the GMO technology itself. Remember that most GMOs have nothing to do with Roundup.
Conclusions about GMO
The GMO technology and the food produced from it is perfectly safe to eat. In fact, it is much safer than traditional breeding of plants and it is safer than other technologies like mutagenesis, although neither of these alternatives are high risk.
Some 89% of scientists agree that GMO food is safe and 57% of Americans say GMO food is NOT safe. This drastic disconnect is both interesting and troubling. The difference may be due to the fact that people do not trust science. It might be due to the fact that the anti-GMO movement has done a tremendous brainwashing job. It is probably a bit of both.
Each GMO plant should be evaluated on its own merits. It is foolish to clump them all into one bucket and call them all bad. The new Golden Rice is a GMO that will prevent thousands of children in poor countries from going blind. There is no science to show it has any harmful effects and the seed will be given to farmers free of charge. There is no large company to blame for getting rich. But people sitting in countries with lots of food on the table are trying to block its use. I find that despicable.
This link is a good discussion as to why Golden Rice is still not be used by most countries.
GMO are here to stay. If it is not this technology it will be another one, but genetic manipulation is not going away. We might as well learn to understand it and start making intelligent decisions about it.
Ignore the fearmongers!
Comments
GMO is such a controversial topic that I will not post people’s opinions. If you have facts to present or references to add to the discussion I will be more than happy to include them in the comment section below.
Excellent as usual, Robert. I have been researching and writing about food production, GMOs and GEs for decades. Most of my knowledge comes from interviews with university professors and scientists, and reading studies relevant to the topic. A few comments: A top Professor of Agriculture at the U of MN said to me once, on the topic of GMO food production, “One of the big factors behind the ignorance of those who protest against GMOs is they have absolutely no idea of the scale of production necessary to feed the world’s population.” Even understanding what he means exactly requires more knowledge than the anti-GMO crowd possesses. I asked him, “What do you think the status of food availability in the US would be if farmers were planting the same seed strains, and raising livestock in the same manner, as they did in the 1940s?” His eyes lighted up, and he said, “What a fabulous question! It would take a bit of work to arrive at an approximate answer, but it’s safe to say that the US would be encountering significant starvation levels, as would the world.”
As for definitions, I also never—NEVER—have a discussion with someone opposed to GMOs (or even someone on the fence) who actually understands what it is they oppose. What they oppose, of course, is Genetic Engineering (GE), the so-called “Frankenfoods” that they fear. Ignorance on the part of the public, and laziness on the part of the media (plus complicity among some of its members) has led to the inaccurate definition that all GMOs are in this category. As you point out, a majority of GMOs do not involve genetic engineering; more often they are created via such centuries-old, man-aided processes as cross pollination. Just as all Azaleas are Rhododendrons, but not all Rhododendrons are Azaleas, all GE foods are classified as GMOs, but not all GMOs are GE. Something the anti-GMO crowd doesn’t even remotely understand.
I usually leave the anti-GMO (actually, anti-GE) crowd with this: World starvation rates, and problems of food availability, are at all-time historic lows. The greatest single reason for this decline is the advent of GMOs, and there isn’t a food scientist of agricultural expert in the world who would disagree with that statement. I’m sick and tired of well-fed, ignorant Americans, their bellies full from shopping huge grocery stores brimming with food, fighting against the science that is critical to creating enough food for millions of suffering humans in Africa, South America, Asia and elsewhere. This isn’t about you.
Well said.
I am really looking forward to new GMO developments – there are some great things coming. And if we don’t call them ‘GMO’ maybe they will be better accepted.
If current levels of corn and soy production were so necessary to prevent starvation why is such a large portion of the harvest channeled to industrial end uses such as ethanol. The entire corn-fed beef industry sprang from need to market a glut in corn/grain production.
Thanks for a well written and well researched article.
Opened my eyes on this topic. Glad to read a non emotional article on GMOs it’s often hard not to get swept up with the groundswell of ‘everything natural’ is the only way to go. So well done on presenting a more balanced viewpoint.
Thank you.
Thanks for a great post that covers all the bases!
It’s sad that anti-GMO sentiment is holding us back from things like golden rice, high omega 3 soybeans, blight-resistant American chestnuts, etc. GM technology is so useful that it’s destined for popular acceptance, but it’s frustrating that we have to spend so much time entertaining irrational fears.
As a person educated in science, I find it both frustrating, and unbelievable. The louder voice always seems to win, even if completely irrational.
Good stuff! Thanks for the education!
Keep up with the good work, Robert
Thanks for the kind words.
Hear, hear!
I bring up Golden Rice when GMOs arise in conversation, most people have never heard of it… But then I live in France, a country with lots of food on its tables.
It is always so refreshing to read such a balanced presentation about GMO’s. The one thing I wondered about is the “super” weeds. It is my understanding that within a given population there are genetic variations that can result in some of the population being stronger than others, thus they are the ones who reproduce when the weaker are killed off. This is similar to what happens with bacteria “becoming” resistant to antibiotics. They are not really “super,” just the ones that have survived.
Exactly the same process.
You wrote a good article, thank you.
I think fear of GMO is fear of the unknown. Also when huge companies make huge profits they naturally become the bad boys, through envy or through hatred of the obscene amounts of money that could, maybe should, be spread around more equally or fairly. Combine GMO and huge companies and you have a perfect entity to hate.
Interesting point about nature doing its own gene modification. I think we all forget that when GMO is discussed. Your point about GMO seed being better tested is probably true but I think many would not trust the results, or would feel only the good results were published. I’ll ignore the testing side for this reason, but that leaves GMO equal to naturally changed genes.
There are plenty of very very dangerous and lethal natural plants and poisons so I think natural mutations are clearly not safe all the time. I’m sure GMO is safe at present because there isn’t much of it about but once they have GMO’d millions of things like nature has then I’m sure they’ll equally make a lot of bad things as well…again making GMO equal to natural mutations.
For me, I’ll keep to simple things. I don’t trust Organic foods any more than GMO but for different reasons. I’ll stick to growing my own where possible, then I have no one to blame but me…and I can live with my mistakes 🙂
Nice post.
I know I’m entering an old conversation but for the people like me reading it new, I want to say the natural vrs science aspect is precisely the problem. People don’t understand just how dangerous nature is. Long ago I had a colleague referring to some medicine or food of something say, if it is natural it is safe. I immediately thought of deadly nightshade, digitalis and monkshood.
I refer to plants because when people like that say nature they mean plants. They do no not mean anything else, not tigers nor pneumonia nor dog tics nor (ahem) novel coronavirus 19.
People have a peaceable kingdom concept of the plant world that is so at odds with what I know. So we start with that problem. And their view of farming is so….gentle.
I’m against Monsanto suing farmers as much as the next person, and wary of salmon genes going into tomatoes etc but how is layering and grafting not technology. How is hand pollination not unnatural? How for that matter is pollination itself not interference? And if as some say, we are part of nature, and nature has no problem using lots of means to get one set of genes to another, does she care if it is done with someone in a lab coat under a roof, the various animals, insects bacteria etc. plants interact with or most common just plain wild mutation?
Because it has not been done exactly that way before? But that supposes that nature is static and unchanging—and surely Darwin clued us in on how wrong headed that is.