Gastrointestinal diseases refer to conditions that affect the stomach, intestines, and other parts of the digestive system. These conditions can include gastritis, peptic ulcers, colitis, celiac disease, inflammatory bowel diseases, and many others. Gastroenterologists specialize in diagnosing and treating these diseases using diagnostic procedures such as gastroscopy, colonoscopy, stool analysis, or specific tests for food intolerances. The goal is to restore the health of the gastrointestinal system, alleviate gastrointestinal symptoms, and improve the quality of life for patients.