I agree, our bodies take care of themselves in this respect. Colon cleansers are a huge scam product plaguing the health industry lately. All of the reputable medical sources advise us to avoid them.
I checked the ingredients for rejuvinex and it sounds like you'd spend an awful lot of time in the bathroom and would feel very bad. It's a very high priced laxative
But it would do absolutely nothing to help you lose fat.