I'm glad that this issue was raised, because I was just considering using Bentonite.
The websites PTree posts are excellent. Jason Eaton , an expert on Bentonite, writes of the uses the government has for Bentonite including a detox for heavy metal poisoning like radiation poisoning. He mentions the healing properties when used externally that he has seen.
He mentions the absorbing properties of the Bentonite (Aluminim Silicate). But I caught him in a couple of mistakes.
He writes that Bentonite creates and has an its own electromagnetic field. This cannot happen because aluminum is not magnetic whatsoever. Aluminum is used for electrical and thermal conductivity, though.
If he is finding a magnetic field, then his bentonite must have traces of magnetic minerals and therefore not pure. This leads me to ask what other impurities are in the clay?
The second area of concern is his statement when treating patients:
"We have noticed that initially patients may worsen... This is due to an increase in circulating bacterial particles and toxins, which promote an antigenic reaction that produces an intense inflammatory response. This provokes increased arthralgias, myalgias, depression, fatigue, and poor memory."
He openly admits the symtoms of aluminim poisoning: depression, fatigue, and poor memory.
My last concern is that Bentonite is a clay. Dr. Clark says you can get parasites from just the soil of the Earth. parasites create bacteria, also.
Jason Eaton admits that patients worsen initially due to increasing bacterial particles and toxins. He theory is that your body is battling itself. The old "You have to get worst to get better. Live through the pain syndrome".
I prefer my own analysis which is that the parasites and bacteria are introduced into the body via the bentonite clay. The aluminum is poisonous. Our bodies naturally want to eject whatever is not good for it.
Jason Eaton, the expert on Bentonite, writes, "I've learned a very few precious things. First, that a "new" fungal infection is much easier to eliminate than an established one. Second, that fungal outbreaks increase dramatically when there is a disturbance in the acid/basic balance in the body...The hard part to consider NOW is what, if anything, is causing an acidic disturbance in the body."
If he studies a little bit more, he will find out that the very Bentonite he is using is causing the acidic disturbance in the body. Silicate is a salt or ester derived from silicic acid. (Sraight out of Webster Dictionary).
I believe there must be a better way to cleanse the colon than subjecting ourselves to clay that is unclean from parasites, bacteria, aluminum poison, and who knows what other toxin metals.