I strongly condemn anyone who claims that a healthy person's colon is full of parasites or anything else harmful. There's absolutely no evidence to support it. It's quackery, in my opinion, to try to make healthy people believe they're sick. They want your money. Bottom line? If you had "parasites" or matter that had never passed, you'd be extremely sick and/or in a lot of pain. Medical tests would confirm that something's wrong. You NEED the bacteria that are in your gut.

Psyllium is a good source of fiber, but I think it's cheaper by the bag.

If it ain't broke, don't fix it. Drink plenty of water and eat enough fiber. That's all your colon needs. It takes care of itself. You don't need to "cleanse" it any more than you need to cleanse your eyeballs.