Nutrition facts are supposed to be reliable. After all, they're regulated by the government and they're the most convenient way to get the low-down on what you put into your body. read more
Diet drinks contain negligible calories, but not many are truely zero. As other have stated, the use of artifical sweetners is the main way of giving that "sugar" taste but without imparting any energy. Some artificial sweetners cannot be broken down by the body and so don't release energy. read more
"Diet soda can have no calories, carbs or sugar because it replaces sugar with artificial sweeteners. Artificial sweeteners are much sweeter than sugar. So it's possible to use a very small amount for the sweet taste and have a very low level of calories," Andrews says. read more