A feeling of disgust about meat can be a powerful predictor of how much meat a person eats — even more predictive than self-control — and may offer a way to reduce meat consumption on a global scale, according to new research on the psychology of eating behaviors.

The study, published May 6 in Appetite, surveyed 711 participants in a sample of 10,000 adults living close to Exeter, a town near Bristol, England. Nearly three-quarters of vegetarians, pescatarians and vegans were disgusted by meat, while only three in 100 omnivores felt meat disgust, the researchers found.

"Meat is such a big and positive part of our culture, that people can be seen as kind of weird for not liking it," lead author and University of Exeter researcher Elisa Becker told The Academic Times. "But everybody can relate [to meat disgust], whether they're vegetarians or omnivores. I've come across a few people who felt really understood and validated."

"More and more psychologists are working on how we can get people to eat less meat," said Becker's co-author, Natalia Lawrence, in an interview with The Academic Times. A better grasp of what drives meat disgust could help cognitive psychologists design interventions for people who want to eat less meat for environmental, medical or ethical reasons, starting with something as simple as an iPhone app. In 2019, Lawrence and other Exeter researchers designed an app-based online game called Food Trainer that helped players lower their meat intake by 22% after just four days.

Eating meat increases one's environmental footprint because raising animals for food produces 14.5% of global greenhouse gases — a greater percentage than the emissions from every car, train, ship and plane on Earth, combined. Yet even as people supplement their diet with plant-based meat substitutes, global meat consumption continues to grow. One recent study showed that the world's population consumed four times more chicken per capita in 2013 than in 1961. 

The Exeter researchers believe these trends need to change, but they see societal and even familial pressure as barriers to be overcome. Lawrence highlighted the theory of the 4Ns as a way to understand how people rationalize meat consumption: most people believe meat is nice, normal, natural and necessary. "I think it's tragic that there are lots of children that are naturally grossed out by meat or just have a disinclination to eat it, and then parents think it's necessary ... My mum used to sort of force me to eat bloody steaks on a Sunday lunch, and I hated it," she said.

Lawrence may have felt core disgust toward meat or one of three other types of disgust that differ based on the stimuli. This first kind comes from obvious pathogen threats such as vomit or spoiled foods that humans evolved to avoid. The second category of injury or animal-reminder disgust is sparked by seeing open wounds and corpses, which remind humans of their own mortality and death. The third category is based on ethical concerns. "Moral disgust is what it says on the tin, really … when you feel disgusted by immoral behavior," explained Becker.

"All of these three types of disgust could be applied to meat. Meat-eating can be seen as immoral; meat could be seen as eating a limb, and meat is quite a bigger threat in terms of pathogens than plant foods," Becker said. "Our study has already confirmed this: Meat is more disgusting, in general, than plants."

Most participants in the study were omnivores or flexitarians, while roughly 15% were vegetarians or vegans. To test the levels of implicit meat disgust, Becker and Lawrence asked the participants to complete an Implicit Association Test that had them quickly sort words or drawings into categories with keys on a computer. Meat and carbs were represented by six images each, which ranged from a full roasted chicken to a potato. Descriptive words such as "foul" and "tasty" were placed in one of two categories: "disgusting" or "delicious."

Becker and Lawrence found a significant correlation between implicit and explicit meat disgust, the latter measured by a questionnaire on eating habits. Becker notes that their design set a high threshold for meat disgust, since participants had to show a strong average across all six different images of meat. "You can't just explain away the 3% of meat eaters who might have been disgusted by one random picture of bacon — the study doesn't work like that," she said.

The co-authors found that 73.6% of vegetarians were disgusted by animal meat compared with only 3% of omnivores. Flexitarians, or those who described their eating habits as, "I try to keep my meat consumption low," reported meat disgust 15.3% of the time.

The researchers followed up with 197 participants six months after the initial survey to gauge whether a feeling of meat disgust varies with time. The amount of meat that omnivores and flexitarians ate tied into the knee-jerk reaction of meat disgust, the researchers noted. Meat disgust was a stronger predictor of a flexitarian's eating habits than self-control, which, in this study, meant resisting the temptation to eat meat. "Emotional responses can be a much more powerful way to change your behavior than using willpower," Lawrence said.

For an upcoming study, Becker surveyed participants during Veganuary, a campaign where people pledge to stop eating meat, eggs and dairy for the month of January as a New Year's resolution. In 2021 alone, the campaign drew over half a million participants. In preliminary results, Becker saw a lower meat intake in people who experienced higher meat disgust, though she is quick to note that a causal relationship is still unproved. "It doesn't bring us any closer to the question of answering what comes first, meat disgust [or meat intake]," Becker said.

"When you do something like Veganuary for a month, you know that meat is obviously not necessary. Maybe those feelings of disgust and guilt that people have deep down" can help reduce meat intake, Lawrence said. "If you stop eating meat for a while, does that more negative side come out?"

The study, "Meat disgust is negatively associated with meat intake — evidence from a cross-sectional and longitudinal study," published May 6 in Appetite, was authored by Elisa Becker and Natalia S. Lawrence, University of Exeter.