Ask and ye shall receiveI summon you, GoldShadow.
The Devil (Tom) made me do it.
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First off, you can't digest leaves because plant cell walls are made of cellulose, which humans can't process. So you'd get just about zero nutrition from leaves.
Regarding vegetarianism for health reasons, both a meat-inclusive/omnivoric and a vegetarian/vegan diet can be healthy. It all depends on what you eat and how much of it you eat. Vegetarians and vegans tend to have more deficiencies in vitamins/minerals/nutrients than meat-eaters, and meat-eaters tend to have more excesses. Some people prefer one diet over for various reasons, but both can be healthy, and it's usually easier to eat healthy with an omnivoric/meat-inclusive diet, as long as you know when to restrict yourself. See the following awesome posts I made in an older thread:
http://www.smashboards.com/showpost.php?p=2854382&postcount=54
http://www.smashboards.com/showpost.php?p=2861782&postcount=62
Regarding whether dairy and meat and some vegetarian-derived foods result in harm to animals, I'd have to do more research to make a strong statement, but Livvers seemed to have covered it pretty well.
As for the moral issue, I think it's quite ambiguous. Where do you draw the line? If you are a vegan for moral reasons, and you don't believe in consuming anything where animals are involved, do you also not believe in taking any medication? Tylenol, diabetes medications, blood pressure meds, HIV meds, all were tested in animals. What if you are an epileptic vegan? Do you stop taking antiseizure meds? And where do you draw the line between which animals matter? Hundreds of thousands of insects were harmed, not only by pesticide use, but also by the process of harvesting the vegetables; yet, by definition vegans also do not believe in consuming honey. It becomes a battle of personal boundaries and where you draw your moral borders.
Anyway I think Livvers and some others have covered this pretty well, I might do a bit of research and post here again.
Also I'd like to take this time to note that Livvers's name appears to come from livers, a bodily organ that is sometimes eaten. Coincidence? I think not.