Skip to main content

The Natural Human Psychology Behind Being Anti-GMO

It's normal and natural to be disgusted by GMOs, but that doesn't mean it's right.
  • Author:
  • Updated:
(Photo: Ken Wolter/Shutterstock)

(Photo: Ken Wolter/Shutterstock)

Anti-GMO sentiment has truly gone mainstream. Earlier this week, the Mexican-food chain Chipotle announced its ingredients are now free of genetically modified foods, a first for a chain. It's a sign of how widespread the desire to avoid GMOs is.

Why are people so opposed to genetically modified foods? Surely there are many reasons, but among them are certain psychological tendencies that nearly all people have. In a new essay, published this month in the journal Trends in Plant Science, a team of philosophers and plant scientists from Belgian universities laid out a couple of these tendencies:


That's not true, of course. Species evolve over time, and people can change species through selective breeding. Without training in the sciences, however, it's hard to intuit this because evolution—and even domestication—usually happens too slowly for any one person to see in their lifetime. Plus, the tendency to classify things into set species might be evolutionarily baked into people, the essay's authors write. Early humans would have needed to learn quickly what tigers are and how they act, and to assume anything that looked like a tiger acted like one, too.

Genetically engineered crops violate people's expectations that species are unchangeable, so they seem weird, unnatural, and monstrous. That also means scientists who work on altering organisms' DNA seem, to many, to be altering something that ought to be unalterable. For religious folks, that translates into "playing God." Yet even those who don't believe in intelligent design are inclined to think, consciously or unconsciously, of natural phenomena as being shaped for a purpose. One recent study found that when physics professors are forced to answer questions under a time crunch, even they fall back on design-based explanations. The professors' scientific training may teach them that such explanations aren't true, but their human tendency is to believe them, especially when they aren't given time to think.

The human bias toward seeing purpose in nature may make even non-religious folks think of plants and animals as sacred. "These intuitions tend to translate in religious beliefs, but they can also contribute to a quasi-religious view on nature," the authors of the new study write. In other words, the bias can translate into a belief that it's not OK to change the current state of nature by altering species, or by releasing altered species into the outdoors.


Disgust is evolution's gift to humanity, to prevent people from making themselves sick by eating rotten stuff. Just to keep people on the safe side, the human disgust threshold may even be lower than strictly necessary. (But also overcome-able through culture. Have you thought about what blue cheese really is?)

This means that people are extra-sensitive about eating foods they find weird. If they find the idea of GMO crops bizarre, then they're not just going to not prefer them. They're going to be repulsed by them. Notably, pharmaceuticals such as insulin are also produced with genetic engineering technology, but don't evoke as much opposition because they aren't food.

Beyond consumption, the idea of disgust also applies to moral reasoning, as psychologists have shown. The issue of GM crops taps into moral disgust because the companies that conduct engineering are often large and powerful. Anti-GMO activists worry about these companies' control over the world food supply, which is warranted in some cases. Once that moral disgust about GMOs is in place in someone's mind, however, it can easily spread to everything related to GMOs, making people oppose GM crops developed by charity organizations and small farms.

Being anti-GMO is a normal, understandable, human stance. It fits in with modes of thinking that humanity has long lived with, and that have long protected us from tigers, food poisoning, and the myriad dangers of the natural world. But evaluating GMOs for what they are—product by product, rather than with blanket disapproval—takes something beyond intuitive thinking.