A vegan diet is not healthy for you. I follow the Biblical diet or the Mediterranean diet.
There's definitely a difference between a vegan diet and a vegetarian diet. Vegans forego all animal products including {GASP} cheese (because it's made from animals' milk). Vegans don't eat eggs, either. They are basically only eating veggies though they ignore the screams of the carrots on whom they commit genocide. Vegans go so far with the anti-animal crap that they will not wear wool or leather products, either, as if the sheep could survive wearing all that unshorn wool; they'd be a chia pet on steroids. If you don't milk a dairy cow that has no calf, they have a tendency to die from bacterial infection from the soured milk, mastitis (an infection in the mammary ducts in the udder caused by a build up of milk which harbors bacteria). Not a quick and painless death by any means.
Vegetarians eat a much healthier diet. I'm no vegetarian, but I do enjoy meatless days; as a kid meatless days were a necessity so my Mom could stretch the food budget (mac 'n cheese dinners. e.g., while today she might have made a pasta with red or cream sauce sauce and cheese). Vegetarians eat eggs and milk and milk products, like cheese. Some vegetarians will not eat animal flesh but will eat seafood.
Given a forced choice, I'd rather go vegetarian than vegan.
I also think a vagitarian diet is not a bad thing.