oomis1105,
When hashem finished creation he looked at everything and said it was very good. According to all opinions, this was the state of the world that was perfect in the eyes of god and eventually when moshiach comes, this is how it will be. Which means we will all be vegetarian. According to many sources including navi, man will be vegetarian once again. All the sacrifices were a means for the people of the time to offer to hashem as opposed to offering them to pagan gods. When the third bais hamikdosh is built, there wont be animal sacrifices. This wont be the same world. I know you may attack me for saying this but look in navi (Isaiah is my source) for this. Who said every mitzvah is based on good health? The kohanim were given many a mitzvah that was not good for their health. For example, if you learn mishnah you will see that they had many ailments from the fact that they had to walk around barefoot in the bais hamikdosh. Dont think that every mitzvah hashem gave is good for your health or not bad for your health. The torah isnt a nutrition guide. This doesnt detract from it, but it belittles it if you think that way. Eating meat is proven bad for your health. Thats undeniable. Its scientific fact. the human body would do well not to eat meat, ever. You belittle Hashem when you say that he would not give a mitzvah that is bad for our health. he gave commandments because he wanted people to follow it. Hashem knows that he designed the body for vegetation. he makes concessions to man. Man has the desire to eat meat.In hashems original world, meat eating would have never existed and in moshiachs days, it wont exist.