I'm not Kristine, and I'm far from an expert on this, but I do have a common sense feel for the issue.

If colon cleansing was a true way of 'cleansing' the body of bad or toxic things, then it would be alot more main stream. Our bodies are made to perfection, really. We have an elimination system that should work properly, when we treat it or feed it appropriatly.

Now, I hope you don't get me wrong here, I have cleansed at home numerous times in numerous ways. I've even done a epsoms salt flush followed by a 5 day juice (organic) fast. I'm the same. Constipation~ any change in your diet can cause this (sans adding fiber).
My fear for someone choosing to cleanse on a regular basis is that the body adapts when it dosen't really have to.
I do believe there are those that have 'slow' colons, but don't necessarily think it's a health issue.
my 2 cents,
Peace,
Brenda

p.s. - aloe vera juice is a great supplement to drink to aid in a healthy colon.!