What Happens When Diners Are Shown Climate Warning Labels on Meat Dishes

The power of the graphic health warning images on cigarette packages that entered widespread usage in the early 2000s has been well studied. Research shows they were successful in deterring people from smoking. In an era of unchecked planetary warming, some researchers wonder whether such a tactic could boost more sustainable behavior. It’s been tried at the gas pump (with inconclusive results) and now researchers are targeting meat.

It seems like it could work. Including a climate warning label on meat dishes in a U.K. experiment reduced how often participants chose meat by 7.4%, according to a new study published in the journal Appetite. Not only that, but the research suggests people would be okay with a policy requiring these types of labels.

Meat has myriad impacts, from increased risk of obesity, cardiovascular disease, and cancer, to environmental pollution, increased emissions, and biodiversity loss. In addition, meat production can spread zoonotic diseases—early in the COVID-19 pandemic, factory farms were among the environments where the virus spread fastest. The researchers wanted to see which category of these concerns—health, climate, or pandemic—would be the most motivating to cut meat consumption.

Led by Jack Hughes, a postgraduate researcher at Durham University’s psychology department, the study surveyed 1,001 adults in the U.K. Four groups of participants were asked to imagine they were in a university cafeteria and had to choose among four dinner options: meat, fish, vegetarian, and vegan. In one group, the meat option came with a warning label that read “Eating meat contributes to poor health,” paired with an image of someone having a heart attack. This saw an 8.8% drop in meat meal choices, compared to the control group. Another group was shown the climate warning label with a picture of deforestation—leading to a 7.4% decrease, while the third got a pandemic warning label with an image of exotic meat. This cut meat choices by 10%.

Studies have shown that meat production contributes a significant amount—in the range of 14% and 20%—of global greenhouse gas emissions. A study from March 2023 warned that at current rates of food consumption the world will surpass 1.5°C of warming by the end of the century, in large part because of the methane that comes from livestock. Switching to a plant-based diet, therefore, can have a dramatic impact.

As part of the U.K.’s strategy to cut emissions, the Committee on Climate Change, which advises the government on its net-zero plans, has called for meat consumption in the country to be cut by 20% by 2030. It was surprising, Hughes told TIME via email, “how large the effect of these labels was”—he thinks they could get the U.K. about halfway to its target.

While the pandemic- and health-related warning labels had more impact than the climate label in the study, they weren’t the most popular as a policy option. Here, participants supported a climate label significantly more compared to the other two. (Or, at least, were ambivalent—whereas most participants actively opposed a policy on health or pandemic warnings.) This implies, says Hughes, “that putting warnings about the impact of meat on meat products might be less controversial than people might anticipate.”

Read more: What to Eat if You Want to Save the Planet and Your Health

The Appetite study is the second of its kind to research the impact of climate warning labels on meat. In a 2021 study, researchers conducted a similar test in the U.S. but with text-only warnings on premade grocery store meat meals. They didn’t find any significant impact of these labels. The difference between the two studies could be due to cultural differences across countries. But, the success of the U.K. study compared to the one in the U.S. could also be chalked up to the inclusion of images alongside text. In addition, the U.K. researchers note, their version included a scientific reference to the source of information (in this case, the World Health Organization, the U.N. Food and Agriculture Organization, and Harvard Medical School), which may have bolstered the label’s effectiveness and credibility.

“It is not up to me to speculate or recommend how companies and restaurants use this research,” says Hughes. “If these were to be implemented in the real world, what our research shows is that putting these warning labels alongside meat options when people are making decisions might be an effective way to reduce the amount of meat people are choosing.”

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