When I am on a water fast I try to completely avoid any calories at all. I occasionally used to drink Zero Calorie drinks because there are no calories so they won’t interfere with my fast.
It turns out that Zero Calorie drinks usually have calories. According to the legal definition a drink can be labeled as Zero Calorie if it contains a up to 4 kcal per 100ml (3.4 US fl oz).
This means that a litre of a Zero Calorie drink is allowed to contain up to 40 kcal!
I thought I’d share this because I didn’t know and if I didn’t then somebody else might not.