Celiac disease develops from an autoimmune response to specific dietary grains that contain gluten. Diagnosis can be made based on the classical presentation of diarrhea, fatty stools, and abdominal bloating and cramping, as well as the presence of specific serum antibodies. In addition, gluten ingestion has increasingly been found to be associated with other conditions not usually correlated with gluten intolerance. The subsequent diversity of the clinical presentation in these cases can complicate decision-making and delay treatment initiation in conditions such as ataxia, headaches, arthritis, neuropathy, type 1 diabetes mellitus, and others. This review explores the etiology and pathology of celiac disease, presents support for the relationship between gluten and other diseases, and provides effective screening and treatment protocols.