Celiac disease is an autoimmune disorder in which the ingestion of gluten—a protein found in wheat, barley, and rye—triggers an immune response that damages the lining of the small intestine. This damage impairs the absorption of nutrients and can lead to symptoms such as chronic diarrhea, abdominal pain, bloating, fatigue, weight loss, anemia, and growth problems in children. Some individuals may have mild or atypical symptoms, while others experience significant digestive and systemic complications. Celiac disease has a genetic component and is diagnosed through blood tests and intestinal biopsy. The primary treatment is a strict, lifelong gluten-free diet, which allows the intestinal lining to heal and prevents further complications.