Master Cleanse Diet.....Detox Question?

Okay, Im not going on the "Master cleanse" diet to lose weight but I have heard that the lemonade works for clearing your body of toxins. However, I have a question. I planned to do the diet for 5 days to clear my body, but when I am done with the detox does this mean I have to stop smoking ( I smoke cigarettes and go to hookah bars sometimes). I am not going to smoke while I am detoxing, but I want to smoke when I get done with the detox. Will I be defeating the purpose of detoxing? Will the smoke bring back ALL of the toxins I cleared my body of or will the cleanse at least clear some of the toxins? Just asking because I told my friend that "I cant wait until this is over to have a cig" and he said everything you got rid of will instantly come back if you smoke.... please enlighten me