A gastroenterologist is a medical doctor who treats digestive system diseases. Gastroenterologists receive training from general physicians. Following medical school, they treat a variety of ailments for three years as medical residents. They then study for three more years in order to become gastroenterologists. With the accreditation, they are acknowledged as authorities on gastrointestinal illnesses and problems. It also grants them the power to do tests and operations that general physicians are not authorized to perform, as well as to interpret the results.