It is not whether or not you eat meat or avoid eating animal products.
Healthy eating means making healthy food choices.
Meat is not unhealthy ... junk food, sugar and refined carbohydrates are unhealthy.
The problem with being a vegan is that the more you cut foods OUT of your diet, the more careful and knowledgeable you have to be about your food choices, to make sure your body gets the nutrients it needs.
Therefore, it takes a lot LESS planning to eat healthy as a meat eater than to eat healthy as a vegan.
And poor vegan planning, even if it is all healthy .. is JUST as unhealthy as eating junk food. Because if you are not getting enough protein in your diet, your body starts eating its own muscle to get the protein it needs. Yes, plants have protein. But not as much. You would have to each 5 cups of beans-and-rice, or 20 heads of lettuce, to get as much protein as there is in one half of a chicken breast.