Reducing your diet’s carbon footprint can be a confusing and often daunting task.
One in four Americans is trying to eat less meat, and one-third of Americans drink non-dairy milk every week, a Gallup poll in 2020 found, but does eating green mean you have to give up meat completely?
In a new study published in the journal Nature Food, researchers from Tulane, Stanford and Harvard Universities revealed how simple food swaps can significantly cut your carbon foodprint without requiring you to totally change what you eat.
“This study shows that cutting dietary carbon emissions is accessible and doesn’t have to be a whole lifestyle change,” Diego Rose, senior author and nutrition program director at Tulane University School of Public Health and Tropical Medicine, said in a statement.
“It can be as simple as ordering a chicken burrito instead of a beef burrito when you go out to eat. When you’re at the grocery store, move your hand one foot over to grab soy or almond milk instead of cow’s milk. That one small change can have a significant impact,” he said.
In their study, the team analyzed diet data from over 7,700 Americans and identified commonly eaten food with the highest climate impact. They then calculated how an individual’s carbon footprint would change when these foods were replaced with nutritionally similar, lower-emission options.
“For us, substitutes included swapping a beef burger for a turkey burger, not replacing your steak with a tofu hotdog,” Anna Grummon, lead author of the study and assistant professor of pediatrics and health policy at Stanford University, said. “We looked for substitutes that were as similar as possible.”
Roughly 26 percent of the world’s man-made greenhouse gas emissions come from the production and distribution of food, scientists estimate, but not all foods are equal when it comes to emissions. Over half of these emissions come from livestock farming, the United Nations Food and Agriculture Organization estimates, despite meat providing only about a fifth of the world’s calorie consumption.
Of these emissions, 62 percent are caused by cows alone, which produce at least 5 times more greenhouse gas emissions than chicken per kilogram of protein, according to data from the FAO. Therefore, switching beef for lower-impact meat like chicken could significantly impact your carbon footprint.
While red meat is a useful source of iron and protein, studies have linked the over-consumption of red meat to an increased risk of cancers, heart disease and stroke.
“There is overlap between sustainable diets and healthy diets,” Grummon said. “Our study shows that changing just one ingredient, making one swap can be a win-win, resulting in meaningful changes in both climate outcomes and how healthy our diets are.”
In total, the team found that making these simple dietary substitutions could reduce the average American’s carbon foodprint by roughly 35 percent while also boosting diet quality by 4 to 10 percent. The largest projected reductions in emissions were seen in mixed dishes like burritos and pasta, where it’s easy to substitute a lower-impact protein instead of beef.
While the researchers emphasize that these simple substitutes are not a cure-all for global climate objectives or personal health goals, they do demonstrate that small, consistent changes can have a large impact.