Senna is the only thing I have ever heard of staining the colon. Did she use a laxative tea, Intestinal Formula #1, or another senna based laxative to move out the P&B? Metamucil is psyllium ground very fine with either Sugar or Aspartame added, and sometimes an artificial flavor. I would rather use just the pure psyllium and skip the additives. Citricil uses cellulose from citrus fruit, but I would rather just eat grapefruit or oranges, its less expensive. I never heard of Bentonite causing staining, people who soak in clay baths clean up pretty goo without staining. I suspect she has used senna either knowingly or unknowingly.