Structural gastrointestinal diseases are those where your bowel looks abnormal upon examination and also doesn't work properly. Sometimes, the structural abnormality needs to be removed surgically. Common examples of structural GI diseases include strictures, stenosis, hemorrhoids, diverticular disease, colon polyps, colon cancer and inflammatory bowel disease.

Your liver is your body’s second-largest organ (after the skin). It sits just under your ribcage on the right side and is about the size of a football. The liver separates nutrients and waste as they move through your digestive system. It also produces bile, a substance that carries toxins out of your body and aids in digestion.

Irritable bowel syndrome (also called spastic colon, irritable colon, IBS, or nervous stomach) is a functional condition where your colon muscle contracts more or less often than “normal.” Certain foods, medicines and emotional stress are some factors that can trigger IBS.