Practicing physicians have dismissed the concept of mucoid plaque as a hoax and a "non-credible concept". 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." Another pathologist, Edward Friedlander, noted that, in his experience, he has never observed anything resembling a "toxic bowel settlement", and that some online photographs actually depict what he recognises as a blood clot. Commenting on claims that waste material can adhere to the colon, Douglas Pleskow, a gastroenterologist at Beth Israel Deaconess Medical Center, stated, "that is the urban legend. In reality, most people clear their GI tract within three days."