Tallying up the carbon cost of your food
A recent study compared environmental impact across different producers for the same foods. Even the lower 10th percentile of beef producers emit 36 times as much carbon dioxide as a typical pea producer. Coffee has a surprisingly large carbon footprint because it’s often grown on cleared land.
What are we looking at here? More evidence that what we eat has an enormous impact on the health of the planet. In a newly released study from Science, researchers collected food production data from more than 38,000 farms in 119 countries. They looked at 40 foods that represented about 90 percent of what the world eats, measuring environmental impact through land use, freshwater withdrawals, and greenhouse, acidifying, and eutrophying emissions. They also evaluated 1,600 processors, packaging types, and retailers.
Beef has the highest impact, followed by cheese, pork, chicken, and fish. Even the lower 10th percentile of beef producers emit 36 times as much carbon dioxide as the typical pea producer. Coffee pops up as a food with an unexpectedly heavy carbon footprint. The study explains that emissions from deforestation and cultivated soils account for 42 percent of the variance in a product’s greenhouse gases. Coffee is often grown on cleared land, but it’s difficult to figure this out in the grocery store.
It also found that the environmental cost of producing the same goods can be highly variable. The authors note: “This heterogeneity creates opportunities to target the small numbers of producers that have the most impact.” Across all products, 25 percent of producers contribute on average 53 percent of each product’s environmental impact.
“What we eat is one of the most powerful drivers behind most of the world’s major environmental issues, whether it’s climate change or biodiversity loss,” says Joseph Poore, a co-author of the paper. Producers need to be incentivized to track impact and make findings transparent to consumer, he adds. Until then, we can’t support the producers who try to be environmentally sustainable.
Here’s a definite takeaway: Eat more plants. If we all cut meat and dairy from our meals, we would reduce food’s land use by 76 percent, greenhouse gases by 49 percent, and acidification by 50 percent.
Emily Zhang is a Stone Pier Press News Fellow based in Palo Alto, CA.