I heard something to do with Nitrogen and …cow farts(?) I am really unsure of this and would like to learn more.
Answer -
4 Parts
- Ethical reason for consuming animals
- Methane produced by cows are a harmful greenhouse gas which is contributing to our current climate crisis
- Health Reasons - there is convincing evidence that processed meats cause cancer
- it takes a lot more calories of plant food to produce the calories we would consume from the meat.
Details about the answers are in the comments
Since you specifically mentioned “cow farts”, you were probably thinking of this: https://www.dw.com/en/fact-check-is-eating-meat-bad-for-the-environment/a-63595148
tl;dr - cattle produces a lot of methane while digesting stuff