Is Pizza Unhealthy?
Pizza can be quite healthy. Whole wheat or grain-free crust (whichever best suits dietary needs), a small to moderate amount of cheese or dairy-free alternative, lots of roasted veggies (onion, bell peppers, broccoli, ect.) homemade pizza sauce, and lean meats if you so desire. Pizzas on the "less healthy" side of the spectrum are genrally pre-packsged, high in sodium/preservatives, made with white flour crust, topped with processed meat(s) and tomato sauce that contains added sodium/sugar, and have few to no vegetables. However, thats not to say frozen pizzas of such ilk cant be enjoyed from time to time.
As others have said, its the excessive cheese and processed meat! Keep it veggie, or use prawns, chicken, or good qualty meat, and add heaps of veggies. I find using cheeses like boccoccini or feta insteaad of mozza keep the fat level down- and they are really tasty!!