What's the problem with genetically modified food?

What’s the problem with genetically modified foods? Every single bite of food I’ve ever eaten has been from a plant or animal with genes that are different than mine, and I’ve yet to experience any problems (other than from some bad lobster, and that had to do with something other than the lobster’s genes, I think). I don’t see how a tortilla chip made with corn that has a genetic make-up which is a little different could affect a person (especially compared to the affect of the chemicals used to make that delicious jalepeno flavor). Blue corn has a different genetic make-up than normal corn, and nobody seems to be getting sick from those. So what’s the scoop?

Combine a suspicion of new things with the “remember thalidomide?” reflex, and that’s what you get.

Besides, the GM foods they’re coming up with are artificially modified, where a genetic engineer inserts a gene for, say, herbicide resistance into a corn gene. The difference between blue corn and regular corn is really only a cosmetic difference–to the human digestive tract, they’re identical. But no one really knows what the long term effects of humans eating corn that has had genes for herbicide resistance artificially inserted into it will be, thus the nervousness.

The plants and animals that you’re eating, although they may have genes different from yours, co-evolved with your primate genes over millions of years, so they’re used to each other. But your primate genes haven’t had much time to acclimate themselves to something that just came out of Monsanto’s experimental labs last year.

Hmm, let me disagree a bit with DGG, while agreeing with the general thrust of the post.

Valid observation, although the Bt toxin is actually used as organic herbicide now. Perfectly safe as its effects are very insect specific, indeed specific to certain types of insects. The real issue is resistance management.

However, for other insertions… Well there might be some real issues lurking. I think in large part the fear is exagerated, however.

I have to disagree in part here. Much of what we eat didn’t coevolve with us. Most of our domesticates are Near East/Asian in origin and even African domesticates are largely from West Africa and not from our “cradle” – presuming OoA North-East-Africa locations are correct.

So, we’ve been adding and manipulating new and whacky things to our diet for perhaps 10k maybe 15k years. Not much co-evolving there. However, the process of experimention is being sped up. And under everyone’s eyes. No longer is Abdullah or George eat the new funny mushroom and keel over, is it simply a local affair. Nope, its global.

In any event, I think if you search the Great Debates forum you will find several recent threads which discuss this very issue. Be sure however to set the limit to 10 or 30 days as I think more than 5 days have passed.

The actual (as opposed to perceived) problems with GM food have less to do with how the genes react with your digestive tract and more to do with not knowing what you’re eating or where the genes are going. One of the problems is that people are allergic to certain foods. If someone allergic to fish eats a tomato that has been rendered cold-resistant as a result of a fish gene they may possibly have an unpleasant or fatal reaction. A similar problem occurs with people with dietary restrictions like vegans not knowing whether their food is ‘safe’ to eat. There’s no way of telling what you may be eating with GM food.
There’s another problem of never knowing exactly how two genes might interact in a GM food source, and it is theoretically possible to get some unexpected end results that could be toxic.
There are also environmental concerns about the genes from GM crops spreading into wild populations and either making weeds herbicide resistant, or making wild plants insect resistant and allowing them become weeds or wipe out wild insects.
I’m not quite sure what you’re saying above Duck. I agree generally with what you’re saying but there are a few points I don’t quite understand. The genes you’re eating in natural corn haven’t co-evolved with our primate genes over millions of years. Humans have only been in North America for what, 10000 years tops? Added to this the genes being inserted weren’t whipped up in Monsanto’s labs last week. They are herbicide or insect resistance genes naturally found in other species and transplanted into corn. Since the species in question are probably Old World species our digestive systems are probably better adapted to cope with them than we are with many of the products of corn genes. Added to this people have little fear of eating novel food that isn’t GM. Nobody really knows the long-term effect of non-Aboriginals eating Macadamia nuts for example. But no-one is likely to suggest they are somehow dangerous because of this.

Some of this has been discussed here:

Another big problem is not so much their affect on humans, but their affect on the environment.
Imagine the disaster if some Genetically Engineered 550lb salmons escaped from the farm and ended up in the rivers. Or some of the insect resistant corn competed with regular corn for survival and regular corn went extinct.

Remember back in the early 90’s when people started getting sick after taking supplements of the amino acid tryptophan ? The government ended up banning sales of tryptophan in health food stores. After several years of investigation, the tryptophan related deaths were found to have been caused by a minor contaminant in the amino acid that only appeared in lots that were produced using a strain of recombinant bacteria specifically modified to increase tryptophan production.
Making arbitrary changes to the biochemical pathways of an organism can have unforseeable and sometimes deadly consequences.

I would also point out that in the U.S., genetically modified products aren’t released to the market until they have been approved by the Environmental Protection Agency, the U.S. Dept. of Agriculture and the Food and Drug Administration. FDA looks for allergic or other reactions, USDA looks for the effect on other species, and EPA looks for everything else.

There has been at least one instance of a genetically modified product being withdrawn from testing after it was found to cause allergic reactions so there are safeguards in place.

When dealing with the possibility of risk, one never says never. But overall, your risk of suffering an adverse effect from a genetically modified soybean is consiederably less than getting sick from the salmonella found on your home cutting board.

The allergy risk and the concern raised by not just vegans but also people whose religious beliefs require dietary restrictions are valid, but mostly because there has been serious resistance to appropriate labeling. If GM foods were labelled as such, and information was available as to what genes had been added, those concerns could be mostly answered.

I think a more serious concern is the role of pesticide resistance. If genetic modification allows farmers to apply pesticides without restraint (because their crops have been made resistant) you can bet that pesticide use will greatly increase. Even if you don’t support organic farming practices (I do) you might wonder if pouring unlimited amounts of pesticide into the soil is really a good thing. You might compare the effect that years of overuse and misuse of antibiotics has had on disease-causing bacteria.

It has also been well documented that pesticide resistance will spread to nearby plants. In other words, the pesticides will no longer be effective against anything. Then what will we do?

Well, this is not really a problem. First, corn hardly competes – both genetically-engineered and “naturally”-engineered corn are pure products of man and utterly incapable of competing in the wild.

Real issues are (a) trait transfer to closely related species esp. wild relative. Not super likely but needs to be studied. (b) I can’t think of B right now. All in all I think the real issue is possible trait transfer to “wild” populations rather than engineered competition with unengineered life.

Okay, too much rum, will go away now.

Pesticide resistance is an interesting issue. On the one hand, having the pesticide genes in the plants can lead to far less pesticide being used. With proper engineering, you can set it up so plants will only express pesticide when and where they’re bitten. A bug starts chewing, and that leaf begins making stuff to kill it. Obviously, this is far more efficient, safer and more environmentally friendly than indiscriminately spraying poison all over acres of crops (and land) at regular intervals.

However, some argue that the efficiency itself is a problem. With more insects getting exposed to the pesticide, due to the targeted delivery, there will be a much higher selective pressure to evolve resistance to the pesticide. And if resistant strains develop, that whole strain of crop, which may have cost millions of dollars to produce, will be useless.

Another concern with engineered pesticide is processing. It’s a different process to get it out of the food instead of off it, like we do now. However, it’s just different - not impossible.

You might want to check out Cecil’s column on this topic:
What’s the story on genetically engineered foods?, which I thought was particularly good. It also spawned a good debate in the Comment on Cecil’s Column forum, Genetically engineered food, in which Cecil himself entered the fray on the very second post.


I was speaking in broad, general terms. Generally speaking, plants and grasses and grains and seeds and nuts and fruits have co-evolved with primates over millions of years. By this time our DNA knows pretty much what to expect from plants’ DNA. Nothing in the last 60 million years of evolution has equipped mammal genes to cope with something that just came out of Monsanto’s experimental labs last year.

And who knows where it all will end? [speaking rhetorically here]


Broadly speaking most plants and animals we use have in no way shape or form co-evolved with primates. As I noted, most domesticates are of West Asian origin. Others are West African. Others are East Asian. They did not co-evolve with primates in any meaningful way. We had little or no contact with much of what we eat until we exited Africa c. 100Ky ago. Our DNA does not “know” anything. Rather, we either tolerate or not the compounds found in any given plant. Much of what is “genetically” engineered is in fact naturally occuring genes producing naturally occuring substances inserted into the genome of a given plant.

To phrase the issue as you are is to badly, very badly misunderstand the issue.

And of course a big part of the problem is companies failure to disclose information to the consumer. In addition, many of the seeds which are genetically modified are much more expensive than standard ones. IIRC, Monsanto seeds were also modified so that they required use of a pesticide made by the same company (“Roundup ready”). The license agreement also required yearly payments to the company. These factors have important ramifications for small farmers, especially in Third WOrld countries who cannot afford the inflated prices for benefits which may not be needed.

So GM foods justly deserve consumer caution. The track record thus far is not encouraging.

Duck Duck Goose wrote:

Not to pile on, but there are a couple of other arguments against this statement. First, virtually none of the food crops that are around today are as they were when man first tripped over them. Our hunter-gatherer ancestors introduced changes to their genes through domestication, long before they started farming. For example, the natural almonds were so bitter as to be almost inedible; the natural peas spilled their fruit on the ground before it was ready to eat; the natural corn ears were finger-sized. Modern versions of them have been genetically modified by our ancestors.

Second, for the last 100 years or so, we’ve been more radically modifying the genes, sometimes through deliberate exposure to radiation or harsh chemicals, with the goal of randomly damaging the genes. The resulting plants are then tested to see if any of them have desirable characteristics. The argument that the bio scientists make is that their art is not different in kind than what we’ve done before - it’s just now more effiecient and precise.

The FDA’s argument against labelling, BTW, is that a mandatory label would imply a safety concern - that’s what warning labels are for - and there is none. If we required labels for other reasons, such as to satisfy political desires like this, then why don’t we require that our produce be labelled to inform us whether the person who picked it was a member of a labor union?

I have read (no cite) that one concern is that seed grain could be engineered in such a way as to make it imnpossible for growers to produce second generations of seed of a crop and would therefore be stuck with buying it from the original source.

This would make subsistance farming in much of the third world far less viable, especially as the genetically modified grain might be of a quality that non-geneticly modified grain would not be able to compete against in world markets.
I have no idea if this is a valid concern, maybe someone could enlighten me.

Could Paprika et al please read the other thread please? I believe information was presented there which puts this in context. In fact there is an excellent link to a WashingtonPost article which I think to be quite good.

In re the dead seeds, that was a program proposed by Monsanto, and renounced in 1998 or 1999. Monstanto, the morons, were brilliant in coming up with public relations disasters through ill-concieved… Anyway, the idiot responsible for those things is out, and Monsanto got bought out. (My dislike for them is of course aimed at a certain chef and his coterie and not my wonderful coleagues there.)

I don’t believe the dead seeds issue is a real threat in the near term, even for 3rd world since first, most present work, for better or worse is aimed at 1st world markets – seeds are a bit expensive for the kind of farmer you’re worried about.

Frankly, I think there has been an immense over-rection.

In re Ready Roundup – hmm, let me see. Walking a fine line here, but the RR seed was made resistant to the Roundup herbicide, or more precisely the particular compound, as far as I recall. This does not require Roundup but it would be rather pointless to plant this seed if you were not a Monstanto Roundup customer. And what’s wrong with that? It’s not like they could muscle folks into using Roundup (and in fact it was compatible with some other herbicides but for licensing resons Monstanto did not, obviously, promote this. There is some legal and other disputes in this area so I will not comment further.).

No, CurtC: speaking as someone working for a non-American major in the field, we’r for labeling. Always have been. We’re always understood, in a way those morons who once were in charge of Monsanto did not, that you have to win consumer confidence. Testing and oversight are our protection. If you read the WP article linked in the other thread you’ll find this was the industry’s historical position.

The above reply sounds a bit nasty, sorry I banged it out rather hastily.

I would like to point out that ALL modern foods are genetically modified. Except we used to call it “animal husbandry” and “plant hybridization.”

Yep, they call that an “F1 Hybrid” and it takes no special recombinant DNA technology to create one. It has been standard practice to produce and sell F1 Hybrid seed corn for many years.