DURHAM, N.C. "Most people do not realize how much food production contributes to climate change – especially meat.
"Beef is a SUV of food," said Rick Larrick, a professor of management and organizations at Duke's Fuqua School of Business.
The enormous carbon footprint of red meat means that even consuming a little less of it – such as replacing something else for beef once a week – can make a big difference to the environment.
"It's just about small changes, rather than anything or nothing," said Larrick, who found the same in his study of vehicles. Switching from a gas-guzzling SUV to a more efficient SUV saves more fuel than going from a compact car to a hybrid that gets 50 miles per gallon.
Larrick has a story to help people understand how much energy they use. With Fuqua colleague Jack Soll, Larrick proposed a gallon per mile standard that the federal government added new bumper stickers in 2013. Later, he designed a drawing to better explain the household's energy consumption.
"Food is one of the areas where we can also make a difference, it's just not so obvious to people," Larrick said. "We can change our diet much easier than we can change which car we drive."
The food system uses large amounts of energy and generates approximately the same share of global greenhouse gas emissions as other important activities, such as transport. But Larrick found that people do not give the same thought to the food's environmental impact.
"When we see a car on the road, or a light in our room, we see the energy used," Larrick said. "But we do not recognize it with the food we eat, because we have never had to articulate all the steps and costs of putting it on our table."
Larrick worked with Adrian Camilleri at the University of Technology, Sydney, Dalia Patino-Echeverri of Nicholas School of Environmental at Duke, and Shajuti Hossain of Duke's Law School on his new research. Their result, "Consumers underestimate the emissions associated with food but can help with labels" appear online in the journal Nature Climate change.
The researchers asked more than 1,000 participants in a national representative test to assess the energy and emissions of greenhouse gases – by producing a serving of 19 different types of food and using one of 18 different devices for an hour. The measurement scale was based on the energy used and gas emissions generated by a light bulb with 100 watts bulb.
Participants underestimated the environmental impact of appliances and food production, but they underestimated the effects of food significantly more than the appliances. A serving of beef releases so much greenhouse gas emissions as running a microwave for two hours. But people equal the effect of beef serving with a 25 watt CFL lamp for an hour.
The same results were held when other metering scales were used, such as the amount of energy and greenhouse gas emissions required to produce a tomato.
The first significant result is the pure underestimate that happens, said Camilleri, who started the research while a postdoctoral researcher at Duke. The second is that people do not understand the big differences in the environmental impact of different types of food, just as we do not do with appliances, he said.
"We know that a central air conditioner uses more energy than a light bulb, but we do not easily recognize how many times more energy they use," said Camilleri.
"People think that a central AC unit for an hour uses about 5 times more power than illuminating a 25-watt CFL for an hour. The AC device actually uses 100 times more power."
The same goes for food, he said.
"One knows, for example, that beef production releases more greenhouse gases than other foods, and they know they can add something to their estimation," said Camilleri. "But overall they are underestimating the meat, because they do not realize how much higher power it has compared to, for example, a serving of corn. Producing and distributing a serving of beef releases about 50 times more greenhouse than putting corn on the table , people think that beef production produces only twice as much as the corn. "
The researchers also found that information to consumers about their food's carbon footprint can affect the choices they make.
For that study, 120 participants were shown six cans of different soups – three steaks and three vegetables – and were asked to buy three cans with the help of some money they received to participate in the research. A group was also shown information that expressed the relative carbon pressure of each soup, using a yellow-green scale and equivalent light bulb mines.
The participants who showed the environmental impact of producing any kind of soup chose smaller beef soup than those that were not – on average about one can each, compared with about one and a half each.
Creating a column label would not be an easy process, but Larrick said that it's only a way to raise awareness.
"We need creative ways to get people this information," Larrick said. "In the absence of information, people just do not think about this and are not aware of their impact on their choices."
CITATION: "Consumers underestimate the emissions associated with food but help with labels", Adrian R. Camilleri, Richard P. Larrick, Shajuti Hossain, and Dalia Patino-Echeverri. Nature Climate change, December 17, 2018. DOI: 10,1038 / s41558-018-0354-z
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