The term was coined by Richard Anderson, a naturopath and entrepreneur, who sells a range of products that claim to cleanse the body of such plaques by causing them to be eliminated.[1]
The presence of laxatives, Bentonite clay, and fibrous thickening agents in some of these "cleansing agents" have led to suggestions that the products themselves produce the excreted product regarded as the plaque.
Practicing physicians have dismissed the concept of mucoid plaque as a hoax and a "non-credible concept".[8] A pathologist at the University of Texas School of Medicine addressed Anderson's claims directly, saying that he has "seen several thousand intestinal biopsies and have never seen any 'mucoid plaque.' This is a complete fabrication with no anatomic basis."
https://en.wikipedia.org/wiki/Mucoid_plaque
Just like with so-called "chronic candida", if the condition was real, autopsies and biopsies would prove it. People are just being conned by Naturopaths trying to make a buck.