But a less expensive and more healthful alternative to beef is something that most people associate with gas: beans. A team of scientists publishing in the journal Climatic Change say that a nationwide effort to swap beef with beans could help the U.S. meet more than 50% of its emissions goals by the year 2020.

The paper emphasizes that beef cattle are the most carbon-intensive food to produce. That’s because cows burp and fart methane, a powerful greenhouse gas. Pound for pound, legumes deliver more calories and more protein than beef with a far, far smaller carbon footprint.

“What this article attempts to show in a very clear way is that a single change in a food habit could have a dramatic effect on greenhouse gas production,” said Joan Sabaté, executive director of Loma Linda University’s center for nutrition, healthy lifestyle and disease prevention, and coauthor of the study. “The nation could achieve more than half of its greenhouse gas reduction goals without imposing any new standards on automobiles or manufacturing.”

Replacing beef with beans isn’t the only option. One recent study suggests that substituting half of the meat consumed worldwide with crickets and mealworms could cut farmland use by one-third. Moreover, the remaining two-thirds could be managed in a more eco-friendly way if we look to kangaroo farts for inspiration, reports Gross Science host Anna Rothschild:

Cows burps release a ton of methane into the atmosphere. Can other animals, like kangaroos, teach us how to make cow gas more eco-friendly?

The good news is that Americans cut their beef consumption from 2005 to 2014 by 19%, according to the Natural Resources Defense Council. An even more dramatic shift in eating habits along these lines could take years or decades—but this new study is the first to indicate that by simply swapping one food for another, we could achieve up to 74% of the greenhouse gas reductions that we need to make our 2020 target.