The 0/0/0 refers to carbs/fat/sugar, so if it has protein it may have a few calories (like egg whites). I was drinking a 6-pack of Zevia a day before I started IP. The problem with most soda is that it is acitic. IP is very alkalizing and because of this, people do not experience the complications that others do on "protein type diets" such as kidney stones, gout, bone spurs... The diet soda (with nutrasweet) is really bad and has been linked to metabolic syndrome. That said, If you decide to have Zevia soda, make sure it doesn't contain phosphoric acid and make sure you drink your water in addition to it. I have not had any soda in 3 months...drinking that much Zevia was an expensive habit.