Study questions those who question GM foods

Extreme opponents of genetically modified (GM) foods know the least, but think they know the most, a new study suggests.

When researchers surveyed 1000 adults in the US they found that as the degree of opposition to and concern about GM foods increased, objective knowledge about such foods, genetics and science in general decreased – but perceived understanding increased.

The same pattern was found in surveys in France and Germany, and to a lesser extent in surveys testing attitudes about a medical application of genetic engineering technology – gene therapy.

However, it did not apply when it came to knowledge and attitudes about the equally thorny issue of climate change. The direction of the effects was the same, but the results were not statistically significant.

“The lack of a relationship between scientific literacy and extremity of anti-scientific-consensus climate change beliefs is consistent with previous findings and we believe that this is attributable to the polarised nature of the climate change issue,” the authors write in a paper published in the journal Nature Human Behaviour.

“For highly politicised issues, ideological commitments may crowd out effects of individual knowledge on attitudes.”

The study team, which was led by Philip Fernbach from the University of Colorado, US, brought together expertise in business and psychology from three universities in the US and one in Canada.

Their motivation was to understand why there is such a gap between scientists and others on the question of GM foods. In their paper, they note a poll by the Pew Research Centre that found 88% of scientists think they are safe to eat, compared with 37% of lay people – the largest gap for any of the issues tested.

Fernbach and his colleagues probably had a fair idea what to expect, given that previous research has shown that self-assessed knowledge is a strong predictor of attitudes and that people tend to be poor judges of how much they know.

Nevertheless, their findings were pretty clear-cut. 

“Across four studies conducted in three countries, we found that extreme opponents of genetic engineering technology display a lack of insight into how much they know,” they write.

Interestingly, extreme GM opponents were more likely than moderates to cite food safety and health concerns.

As expected, people were more accepting of medical applications of genetic engineering than food applications, but the same patterns emerged. Extreme opponents were less knowledgeable – but thought they were more knowledgeable – than moderates, and they were also poorer at evaluating their level of knowledge.

The studies were comprehensive, seeking to test for general as well as specific knowledge and to account for levels of education. And they add more fuel to the debate about the role and direction of science communication.

“Our findings highlight a difficulty that is not generally appreciated,” Fernbach and colleagues write.

“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.

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