Foods that are high in insoluble fiber, lactose, and sugars may trigger symptoms of ulcerative colitis. Working with a healthcare professional may help you identify which foods to avoid.Ulcerative colitis (UC) is a chronic inflammatory bowel disease (IBD) that can affect your colon and rectum. Your diet and gut bacteria may play a role in the onset of UC symptoms. Keep reading to discover foods that commonly trigger symptoms of UC.Whole grainsWhole grain products are typically high in fiber, which may be hard to digest if you have UC. A low fiber diet is recommended during a flare-up because it may help reduce the frequency and volume of bowel movements. Whole grain flour is high in fiber because it hasn’t had the germ or bran removed. Other whole grain starches still have the fibrous endosperm, germ, and bran that may irritate UC and trigger a flare-up.Below are whole grain foods that you may want to avoid during a flare-up:Whole grain flourOther whole grain starches• breads• cereals•...