Also, a normal can of Diet Coke will have around 130 mg of aspartame. The amount of aspartame within that single can be broken down into a protein. All proteins have some caloric value. When you calculate the amount of this "protein" in a single can of Diet Coke, you get 118 mg of aspartylphenylalanine. That equates to a normal can or bottle of Diet Coke containing less 0.576 calories. This is a very small number, but it is not “without calories” as you erroneously claim.