A new analysis drawing on 570 studies with data covering 38,700 commercial farms shows dramatic variation both worldwide and within-region in the environmental impact across all major foods, but confirms that beef in particular and animal products in general are responsible for the greater part of food’s impact on earth, which adds up to 31% of global warming emissions (including non-food agriculture), and 43% of ice- and desert-free land. Supplementary material available for free (and is very comprehensive), while the main article is for subscribers only (here).
Poore, J., & Nemecek, T. (2018). Reducing food’s environmental impacts through producers and consumers. Science, 360(6392), 987-992.