Cheerios’ GMO-free claim is marketing, enabled by industry critics

FORTUNE — We can make fun of General Mills (GIS) for bragging that it will soon offer “GMO-free” Cheerios. It’s an essentially meaningless marketing stunt. But we should also know that it is in part the actions of many critics of genetically modified crops that made such a move possible to begin with.

So far, there’s no indication that any other companies are planning a similar move. Doing so would be tough for many cereal makers, including General Mills itself, since so much cereal is made from corn (the U.S. crop of which is 80% genetically modified organisms) or contains other GMO ingredients. The Honey Nut variety of Cheerios, for example, contains corn, so it can’t bear the label. But companies that produce food that isn’t made with GMO ingredients might pile on. Products made with wheat, such as bread, could easily include the “GMO-free” label since, as with oats, there is no commercially available GMO wheat (at least, for the time being).

If other brands were to follow General Mills’ lead, it would be a bit like what occurred a few years ago with high fructose corn syrup: The loudest critics of the substance, by focusing on problems that weren’t actually problems (for instance, that HFCS was “poison“), helped HFCS producers ignore the real concerns about the substance. The Corn Refiners Association developed a series of highly disingenuous ads combating the “poison” claim, then tried unsuccessfully to change the name of HFCS to “corn sugar.

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They also gave the food industry an opening: Many food makers started bragging on labels that they contained no HFCS but were made with “real sugar.” From a health perspective, the difference between HFCS and sugar is essentially zero. Both are bad for you, about equally. HFCS has surely expanded the American waistline and has surely led to increases in the incidence of diabetes and other diseases. But that has to do with economics and politics, not with the substance itself. If sugar were just as cheap, it would be equally ubiquitous, and we would have the same problems. And it’s the ubiquity of HFCS that has caused the problems. Corn is heavily subsidized, so compared to sugar, where prices are artificially high because of tariffs, corn-based sweeteners have historically been cheap. HFCS is partly responsible for super-sized fast-food meals where in some cases every component — the giant soft drink, the large order of fries, the condiments on the burger, and even the bun — contains HFCS.

GMOs aren’t poison either, but you might not know that if you listened only to their loudest critics, many of them either charlatans or science-ignoring ideologues. The overwhelming scientific consensus is that GMOs pose no health threat, and yet the public debate is currently centered on whether the government should force food companies to put warning labels on products that contain them — a requirement that normally is reserved for substances that might be hazardous to human health (such as “May Contain Peanuts”). Nathanael Johnson of the environmental news site Grist, who started out as a GMO skeptic, learned after delving deeply into the issue: “When you consider the evidence in sum, the products out there look pretty darn safe.”

Sunday’s epic New York Times article by Amy Harmon — describing how Greggor Ilagan, a member of the Hawaii County Council, learned all about GMOs before voting against a ban of them on the Big Island — tells the tale as well as anything: Harmon, virtually looking over Ilagan’s shoulder as he did his research, shot down myth after myth, both health-oriented and environment-oriented: that GMOs might cause cancer, that they cause childhood allergies, that they are responsible for vanishing bee populations. There is no solid evidence for any of these claims (nor for many others), and yet those are the kinds of claims that are being debated. The anti-GMO people Harmon depicted seemed motivated more by anti-corporate sentiment than by genuine concerns about GMOs. As Marion Nestle, author of Food Politics, has said: GMOs work as a “surrogate for what people really worry about but aren’t allowed to discuss: corporate control of the food supply.”

All of which makes it that much more mysterious why more anti-GMO advocates don’t redirect their criticism toward the real problems posed by GMOs. They mention them sometimes, but often after yelling “CANCER,” or using scare terms like “frankenfoods.”

One problem is that both the benefits and the drawbacks of GMOs are full of caveats. For instance, GMOs have reduced the need for insecticides, which is good, but there are already indications that insect resistance is growing. And GMOs have increased the need for herbicides in a huge way. The caveat there is that while use of the herbicide applied to many GMO crops (which they were bred to stand up to), glyphosate, has increased, the use of other, more harmful herbicides has decreased. The caveat to that caveat is that there is some indication that glyphosate might threaten butterfly populations. Furthermore, weeds, like insects, develop resistances, and some farmers are using highly toxic herbicides to rid their fields of the so-called superweeds that after a time are able to overcome GMO crops. (The New York Times‘ Harmon sort of glossed over the superweed problem).

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Another huge problem that goes under-addressed is the market power that companies like Monsanto (MON) are able to wield through their ownership of seed patents. Many farmers who have saved seeds instead of buying new ones from Monsanto have been subjected to lawsuits over the practice. But this has as much to do with our broken patent system as it does with bad corporate behavior on Monsanto’s part. And the Supreme Court last year essentially upheld Monsanto’s right to file such suits. (Monsanto has posted a standing statement in response to criticism of its suit-happy ways.)

On balance, the presence of GMOs in crop markets has helped more than hurt the farm economy as a whole. But as Grist’s Johnson points out, it could be that rich farmers are getting richer by planting GMO seeds, while poorer farmers aren’t improving their lot at all.

There are many more issues surrounding GMOs, both pro and con, but none of them are so clear cut as to make “GMOs,” as a concept, logically assailable. (After all, genetic modification has been going on since soon after agriculture was devised, via cross-breeding). Intellectually honest skeptics are left to expose the many downsides one by one. It’s easy to see how actually diving into the details of GMOs (or HFCS) makes it disingenuous to argue by slogan. But that’s just what too many activists seem determined to do. Unfortunately, it doesn’t help anybody understand anything, and it gives the food industry an opening to make meaningless marketing claims that are founded on misinformation.

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