You're question is kinda rules-lawyery. It would break a water fast. Joe Cross fasted for 60 days on vegetable juice and made a movie about it; he lost 100 po

You're question is kinda rules-lawyery. It would break a water fast. Joe Cross fasted for 60 days on vegetable juice and made a movie about it; he lost 100 pounds, but yes its not a water fast, but that's somewhat the point of my comment, that there's more to fasting than simply not eating.