A 2015 Pew survey found that 88% of AAAS scientists believe that GMOs (genetically modified organisms) are generally safe to eat, while only 37% of the general public did. This was the biggest gap, 51%, of any science attitude they surveyed – greater than evolution or climate change. This hasn’t changed much since. A 2018 Pew survey found that 49% of US adults think that GMOs are worse for your health. These numbers are also similar in other countries.

An important underlying question for science communicators is – what is the source and therefore potential solution to this disconnect between experts and the public? In other words – what drives anti-scientific or pseudoscientific attitudes in the public? The classic answer is the knowledge deficit model, that people reject science because they don’t understand it. If true, then the answer is science education and fostering greater scientific literacy.

However, psychological research over the last two decades has called into question the knowledge deficit model. Studies have found that giving facts often has not result, or may even create a backfire effect (although to scope of this is still controversial). Some research suggests you have to confront a person’s explanatory narrative and replace it with another. Others indicate that ideological beliefs are remarkably resistant to alteration with facts alone.

But the knowledge deficit model is not dead yet. It seems that we have to take a more nuanced approach to unscientific beliefs in the public. This is a heterogeneous phenomenon, with multiple causes and therefore multiple potential solutions. For each topic we need to understand what is driving that particular belief, and then tailor an approach to it.

For anti-GMO beliefs it seems that the knowledge deficit model may be largely accurate. First, anti-GMO beliefs do not align strongly with political identity (unlike, say, global warming denial). It also doesn’t align with religious identity (unlike anti-evolution beliefs). In fact, there is no strong association with any demographic – gender, politics, income, or education.

However, strong opposition to GMO foods does correlate well with scientific knowledge. Extreme opponents know the least about the science of genetics and genetic modification but believe they know the most. The relationship between actual knowledge and self-assessment of knowledge is positive generally, but as opposition to GMOs increases the relationship flips, with increasing self-assessment correlating with less knowledge.

For a quick review, the Dunning Kruger effect does not show this flipped relationship – there is still a positive correlation between knowledge and self-assessment throughout the curve, only the difference between the two changes. So extreme anti-GMO attitudes are worse than Dunning Kruger with increased ignorance correlating with increased self-assessment – the curve actually changes direction.

So the lack of correlation with ideological identity, and the positive correlation with lack of knowledge suggests that perhaps anti-GMO attitudes may be a genuine manifestation of the knowledge deficit model. Well, a new study tests that hypothesis. The authors conducted four studies:

Results from Studies 1 and 2 demonstrated that knowledge of GM technology is a unique predictor of GM food attitudes above general science knowledge and demographic controls.

So first they confirm the knowledge deficit hypothesis, and show that specifically lack of knowledge about GMOs, more so than general science knowledge, predict opposition. In study 3 they replicated these findings between the US, UK, and the netherlands, to show that it is fairly generalizable. In the fourth study they wanted to know if an intervention would be effective:

In Study 4, we sought to overcome this lack of knowledge by teaching people the basic science behind GM technology using a five-week, longitudinal experimental design. Results showed that learning about the science behind GM technology leads to more positive explicit attitudes towards GM foods, greater willingness to eat GM products, and lowered perceptions of GM foods as risky.

So at least for this one topic, the knowledge deficit model has some teeth. We can get traction just by increasing domain-specific scientific literacy.

This probably stems from the ultimate cause of opposition to GMOs. I do think it is based in part to the fact that genetic technology is inherently complex and scary. But I don’t think that fully explains it. We also have to explain the disconnect between knowledge and self-assessment for those who are strongly anti-GMO. This suggests not just lack of knowledge, but misinformation that gives the false illusion of knowledge.

There is a similar relationship between knowledge of the causes of autism, self-assessment about this knowledge, and opposition to vaccines. This is another situation in which misinformation is likely playing a prominent role.

Misinformation seems to play an important role in any anti-scientific belief system, but it may play a larger role in some vs others. For any particular anti-scientific belief there is a combination of scientific ignorance, misinformation, conspiracy thinking, denialism, psychological factors such as confirmation bias and fear mongering, and appeal to religious, cultural and political ideology and identity. But the balance of these factors is different for different topics.

For example, opposition to evolution is dominantly about religious identity. Other factors play a supporting role only, but religion is the driving reason. For opposition to the science of climate change the demographics show it is entirely predicted by political identity.

For anti-GMO attitudes what I see and what the evidence now supports is that opposition correlates with general lack of scientific knowledge, specific lack of scientific knowledge about genetics and genetic modification, specific misinformation about GMOs (probably the biggest factor) and then other factors play a small supporting role, and vary based on the individual’s demographics. So liberals will cite corporate malfeasance, libertarians will cite government overreach, and new agers will focus on GMOs being “unnatural.” Meanwhile those in developing nations often appeal to technological imperialism.

These are all justifications or pretexts to opposition to GMOs, but the driving factor seems to be specific misinformation resulting in fear and disgust (both physical and moral). The good news is – that is a problem that can potentially be fixed. This may be one domain where science education itself can be significantly effective.

Again, this fits my personal experience. Whenever I have the opportunity to speak at length with someone who is anti-GMO, I can always identify specific misinformation and correcting it seems to have an effect. The emotional connection for most people seems to be fairly light, and they are happy to update their beliefs with new information on this particular topic.

We therefore also need to address the anti-GMO misinformation campaign head on. That is what is really driving anti-GMO attitudes. This is something that any scientist or science communicator can do. It doesn’t require specialized knowledge about conspiracy thinking or other critical thinking factors (although that doesn’t hurt). Scientists need to engage with the public and turn this ship around.