A clever study suggests that you simply can’t unknow your food’s carbon footprint

Carbon footprint labels cause people to choose meat products with 25% lower climate impact, according to a study of hypothetical purchasing decisions conducted in Sweden. The study lends support to an emerging strategy of carbon labeling in grocery stores—but suggests such labels have to be carefully designed in order to reach those who might rather not think about the environmental impact of their food.

The global food system is responsible for at least one-quarter of all greenhouse gas emissions, and meat has an especially large carbon footprint. Consumers know relatively little about the climate impact of food, prompting the notion that providing more information might nudge them to make more climate-friendly choices.

But there’s also evidence that people avoid uncomfortable information in a variety of realms, including food purchasing. For example, people sometimes turn down the opportunity to learn about the calories in a package of cookies, or the animal welfare issues associated with mass-produced meat. In essence, people may avoid information that they suspect will challenge their beliefs or make them feel bad about their choices in some way.