Here's a funny one: genetically modified food. Okay, so maybe it's not all that funny. But people's reactions to it certainly are.

Despite numerous and huge scientific studies validating the safety and benefits of genetically modified foods (aka GM or GMO foods), people just refuse to be convinced.

Should we be surprised? Perhaps not: Americans on the whole don't know a lot about food.

The delicious irony in all of this knowledge lacking is that – when it comes to GM foods, at least – many of those who think they know the most actually turn out to know the least.

But don't take my word for it.

A new study led by marketing researcher Phil Fernbach from the University of Colorado Boulder surveyed over 2,000 adults based in the US, France, and Germany about their opinions on GM foods.

The researchers also asked participants how well they thought they understood the topic of GM foods, and tested their knowledge of science and genetics with a series of true-or-false statements.

For example: "Ordinary tomatoes do not have genes, whereas genetically modified tomatoes do". Or this one: ""All plants and animals have DNA".

The results were illuminating.

"As extremity of opposition to GM foods increased, objective knowledge of science and genetics decreased, but self-assessed knowledge increased," the authors explain in their paper.

In other words, those who were the most strongly opposed to GM foods in the experiment tended to believe they were highly knowledgeable on the topic, but actually demonstrated decreased understanding of science and genetics compared to other participants.

It's amusing, sure, but according to the researchers, isn't actually surprising.

"This result is perverse, but is consistent with previous research on the psychology of extremism," Fernbach says.

"Extreme views often stem from people feeling they understand complex topics better than they do."

According to the team, results like this reveal a strange, self-perpetuating paradox that makes it difficult to confront the knowledge imbalance.

The phenomenon – also known as the Dunning-Kruger effect – isn't just confined to GM foods, but can exist in other areas where people with extreme and overconfident views misconstrue science (and their own limitations).

"Those with the strongest anti-consensus views are the most in need of education, but also the least likely to be receptive to learning; overconfidence about one's knowledge is associated with decreased openness to new information," the researchers explain.

"This suggests that a prerequisite to changing people's views through education may be getting them to first appreciate the gaps in their knowledge."

Scientists of the world, good luck with that.

The findings are reported in Nature Human Behaviour.