Hi Dolphinlvr4 !
I've been veggie as a child, and the became vegan in my twenties. My children are vegan & husband veggie (has dairy in some things & eats eggs). We have only seen doctors for sports injuries, because we had to, to get a note to return.
I think most people end up being sick or having issues when they are not eating healthy. Being vegan you can eat oreos & fritos, and of course some prepackaged meals, all of which contain things that aren't really good for you. Processed foods in general cause health issues.
If you are thinking about changing your diet, I would do it slowly and just by adding a few changes daily. Any change can make you feel blaa until your body is able to be free of the toxins. That's why most people feel really crappy during the second to fourth day of a cleanse. Veggies clean your body out and it can even make some people depressed for a week or two.
This is a good site with info on how and why it's best to be veggie/vegan:
http://michaelbluejay.com/veg/natural.html
If you'd like someone that has recipes and random info posted, Elena's site is great !!
http://www.vega-licious.com/