I gave up arguing for and against veggie/vegan diets years ago, and generally keep my personal dietry habits to my self, but going back to the origanal question of the thread here goes......
My experience of being veggi, Started when I was burning the candle at both ends with a blow torch in my early 20's, met the future Mrs andyf who was/is veggie and put me on salads and veggies instead of Mcdonalds, fags and booze (never gave up the booze though
)
Became a 99% veggie for years yet my not so good health and panic attacks never stopped, untill I went to see a kinesiologist who said my body was craving for protien and my adrinal glands and other organs where over sensative because of it, and with to much simple sugers and carbs in my diet (and no exersise)
She started me on protien shakes and with in a week or so the panic attacks that I had suffered for years ( thinking I had a mental illness/stress and taking shit loads of herbal chill out tablets/sprays) just floated away....................
So my point is you need to listen to you body, some of us are natural veggies/vegans and others like me need to be carefull to keep things in-balance.