Vegan

Yeah, raising cattle produces a ton of greenhouse gases from the usual industrial agriculture sources - growing feed for livestock, transporting animals, processing animals, etc.

And above that, cows specifically produce a lot of methane, and feeding them grain in feed lots produces even more methane than normal, because it's not the diet they evolved to eat, and methane is such a powerful greenhouse gas it doubles the overall impact of cattle production.

If you eat an average Western diet, cutting beef from your diet would benefit the environment more than cutting any other single food, by far.

Tldr cow farts.