Hjemmesiden Vox.com skriver bl.a:
Food production is responsible for about 25 percent of the greenhouse-gas emissions heating up the planet. And scientists have long known that meat has a bigger climate footprint than fruits and vegetables do — partly because meat takes more energy to produce, but also because cows tend to burp up a lot of methane. (Cows, in turn, have a larger impact than pigs or chickens.) That’s why, last year, a US nutritional panel advised Americans to consider eating less meat for environmental reasons. “A diet higher in plant-based foods … and lower in calories and animal-based foods is more health promoting and is associated with less environmental impact than is the current US diet,” the Dietary Guidelines Advisory Committee said.
Kilde: Study: Going vegetarian can cut your food carbon footprint in half – Vox