this is my first time on Master-Cleanse but I quit smoking on a green juice fast and it worked out really well. Because you are not eating solid food the nicotine in the sytem is gone in about 24hrs. So the physical withdrawl is not bad at all. Also all those food triggers are gone so you won't be temped to smoke. The morning coffee and cigerette, the after a meal cigerette, etc. So you habits change. I think it a great way to stop smoking. I had tried to quit 2 times before and went back to smoking after a short time. When I quit with the juice fast I was successful and have not smoked since. Good luck!