Does Coca-Cola Convert rust? Results

What I want to know is why phosphoric acid is in Coca-cola in the first place... makes sense every once in a while I drink a coke my teeth feel like they're dissolving (because they basically are)
FYI, sodas are terrible for your body. They spike your blood sugar badly, and are made with corn syrup for sweetener which is especially bad. Nothing good about them. I stopped drinking them, lost 15 lbs, and feel much better. If it can clean out the sludge in a car radiator, then its probably not very good to consume.