claim: In the process, the cows will emit much greenhouse gas, and they will consume far more calories in beans than they will yield in meat, meaning far more clearcutting of forests to farm cattle feed than would be necessary if the beans above were simply eaten by people.”
evidence: A simple exchange of beef to soy beans ( a common feed source for cattle ) in Americans' diets would, according to one estimate, result in meeting between 46 and 74 percent of the reductions needed to meet the 2020 greenhouse gas emission goals of the United States as pledged in 2009.