anybody experience with juice fasting?

hello!
i read this one 30 day diary about juice fasting. does anybody know what The Master Cleanse lemonade is made of? also does one have to use laxatives for a "complete detox"? i'm always a bit worried that it's not good for your body. also i'm 5'9 and weigh 125 pounds and really want to do this for detox rather than loosing weight. is there any risk?
thank you so much :)