Colloidal is a term used for any substance that consists of fine particles that remain in a liquid suspension...in the case of Bentonite this enables it to have an enormous surface area allowing it to absorb more toxic material. This is why liquid Bentonite is preferred over powdered bentonite...the surface area is far greater.

Fiber has numerous health benefits...particularly soluble fiber including psyllium. Soluble fiber...the ones that absorb water and form a gel-like substance...help to lower blood cholesterol levels by sweeping bile acids out of the body and eliminating them in fecal material. These bile acids would otherwise convert to cholesterol and...in turn...promote healthy heart functioning. It is also beneficial in the management of diabetes and some cancers...not to mention all the good things it does for the digestive system!

Here's a link to several articles on the benefits of fiber:

http://www.md-phc.com/fiber/indexfib.html

Good luck with the cleanse!