Well considering nearly, if not all modern offshoots of Christianity are rooted in Catholocism, I don't really see why you they need to be separated so. The communions practiced in protestant offshoots are kind of bound to their origins no?
And once again, symbolically eating the flesh and blood of your deity can be referred to as symbolic ritual cannibalism, whether or not you believe that it is literally turning into the blood and flesh of your deity in your stomach.