Stopping or reducing dietary fiber intake reduces constipation and its associated symptoms . Lack of fiber in the diet was first postulated in 1971 as the cause of diseases such as diverticulosis, hemorrhoids and colorectal cancer[1]. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3435786/
Tight junctions in inflammatory bowel diseases and inflammatory bowel disease associated colorectal cancer https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4789987/