I fully support the argument posted by Preeto/Bebe/etc that shows that Guru Nanak Dev ji did not care for what food you eat, as long as there is simplicity. We eat to stay alive, like Guru Nanak Dev ji says God could've made any animal a vegetarian, God could've made you a vegetarian and I a non-vegetarian, it does not matter what we eat.  What matters is if you remember God when you eat (and at all times), if you thank God for letting us survive/live another day.  Eh rizak sab ohda ditta... "Tera ditta khawna"

Thank you preeto ji for posting this argument.  In the end, Guru Nanak Dev ji kehnde ne ke sirf moorakh hi eh sochda hai ke kuch khaan ja naa khaan naal tuhadi bhagti/spiritual-life vich kami aa sakdi hai.
u right bro i agree with u