Unfortunately, no one can answer the question of whether a juice fast or the Master-Cleanse is better for cleansing and losing weight FOR YOU. I don't know enough about juice fasts to even recommend one, but I do know that they can be used for cleansing. I personally love the Master-Cleanse and it works for me, but I know it is not for everyone. There is a lot of information on juice fasts both here and on the internet. Good luck with whatever you decided to do.