You can also be very healthy without eating a vegan or vegetarian diet. You can't compare vegans who avoid stuff like Oreos and other junk to people who eat processed meat. You should compare health conscious people on both diets.

Most of the health benefits from a vegan diet are also attributable to a vegetarian one, and most or all of the benefits from a vegetarian diet are also attributable to a health-conscious, whole-foods (i.e. - not processed), organically-raised (i.e. - grazed rather than corn-fed cattle; no antibiotics in your meat; free range chickens; traditional-agriculture as opposed to Agri-corp agriculture, etc) foods.

Also your genetics play a huge role, and there is no diet that is perfect for everyone.

Anecdotally, I eat meat and I'm very healthy, because I avoid processed and unhealthy food. My mother and sister are vegetarians and are fat and are borderline diabetic.

People who go a step further and become vegans would be smarter and more knowledgeable and health conscious than the regular person