Why Do People Hate GMOs?

Maria Konnikova looks at the psychology of folks' complete distrust of genetically-modified foods:

In a 2013 study, a group of Cornell University researchers found that how a food is labelled affects our perception of how it tastes, what its nutritional value is, and our willingness to pay for it. A hundred and fifteen shoppers at a local Ithaca mall were given three different food pairs. One item in each pair was labelled “organic” while the other was labelled “regular.” (In reality, the two items were identical, and both were organically produced.) The shoppers were then asked to rate the taste and the nutritional value of the products, as well as to guess at calorie counts and say how much they’d be willing to pay for each item. The researchers found that people's calorie estimates for the organic foods were consistently lower: an organic cookie, for example, was seen as approximately twenty-four per cent less caloric than a regular one. They thought the organic food tasted less artificial and was more nutritious over-all. They were also willing to pay somewhere between sixteen and twenty-three per cent more for the organic items. They were, essentially, experiencing something known as the halo effect, a phenomenon whereby one positive attribute of a person or thing colors other, unrelated characteristics in a positive light.
G.M.O.s, in contrast, suffer from a reverse halo effect, whereby one negative-seeming attribute (unnaturalness, in this case) skews over-all perception. In a 2005 study conducted at Maastricht University, in the Netherlands, researchers found that the more unnatural a genetically modified product seemed, the less likely it would be to gain acceptance. A hundred and forty-four University of Maastricht undergraduates were asked to visualize seven products, including butter, tomatoes, and fish fingers, and rate them on naturalness, health, and necessity. They were then asked to imagine genetically modified versions of the same products and respond to three questions: how morally justified it was to eat the food, how much they trusted it, and how natural they perceived it to be. As expected, the scientists found that the less natural a food product seemed, the less likely the participants were to trust or eat it. There was, however, an interesting caveat: if an original, non-modified product was made to seem less natural or more processed to begin with, people became far more likely to trust and accept the genetically modified equivalent.
The negative halo of G.M.O.s doesn’t just affect how we feel toward them; it also impacts how we evaluate their attending risks and benefits. As early as 1979, the psychologist Paul Slovic, who has been studying our perceptions of risk since the nineteen-fifties, pointed out that, when it comes to new, unknown technologies, data always loses out to emotion. For instance, people judge the risks of radiation from nuclear power plants to be much higher than those from medical X-rays—a conclusion that is not backed up by the data and is at odds with the advice of most risk experts—simply because nuclear power plants seem more foreign and inspire greater dread. What’s more, when we’re in a state of heightened emotion, we don’t weigh risks and benefits equally—risks take on an outsized impact and benefits begin to pale in comparison.
Once an initial opinion is formed, Slovic continues, it is very difficult to shift it with new evidence: the exact same piece of information—say, additional data on the effects of G.M.O.s on a natural ecosystem—can be interpreted in opposing ways, depending on your starting point.

I never really understood some of the fears of GMOs.  How would the BT gene addition be so dangerous?  I've never really understood some of the Monsanto conspiracy theories floating out there.  Anyway, it is good to try to understand what makes folks tick.