sentences:  Recent findings have called this hypothesis into question; specifically, the hair and nail changes may not improve with improved nutrition.Other conditions consisting of multiple hamartomatous polyps of the digestive tract include Peutz–Jeghers syndrome, juvenile polyposis, and Cowden disease.Related polyposis conditions are familial adenomatous polyposis, attenuated familial adenomatous polyposis, Birt–Hogg–Dubé syndrome and MUTYH.