Alrighty, this is stuff I actually study, so I can contribute. weee.
Ok, the straight poop (pardon the pun) on colon cleansings is this basically.... its a high fiber diet with lots of water. Go read the labels, they pretty much have one thing in common.. the fiber equivalent of eating a wicker chair. if you want to look at it from the holistic side, just basically picture fiber as natures little scrubbie pad for your intestines, alrighty?
most of the items you'll see in most cleansings and treatments are basically 'just eat good food and complete meals'.
Other methods are good for purposes not really in their descriptions.. skin cleansings? you know, that whole bathe in apple cider vinegar & epsom salts for 30 minutes and scrub yourself? Can't really day it pulls heavy metals out of your skin, but used daily for a week or two, its one hell of an exfoliator