Isagenix 9-Day Deep Cleansing and Fat Burning System #2

I finished the 2 shake days (pre cleanse) and 2 of the cleanse days. The cleanse days suck. The first one was really hard, the second one was manageable. Now I have 5 more shake days followed by two more cleanse days. I'm not sure how effective this system is for deep cleansing. It's also pricey. I won this system through a giveaway that is why I'm trying it for myself. I have lost 3 lbs. so far. The question is what do I have to do to keep from putting the weight back on after the cleanse is over?