Posted: Yesterday at 18:29
Cows have two stomachs and can process cellulose unlike humans.
I don't think it's hard to pass on meat and fish if that's your thing but I suspect veganism is quite feasible too. You'd need a lot of protein supplements mind you.
Depends on the level of training too. If you're getting off hd couch to run a 5k once in a while and lose weight no problem. If you have your heart set on a team GB vest forget it