National Celiac Disease Awareness Day is observed in the United States every September 13. This day aims to increase public knowledge about celiac disease, an autoimmune disorder triggered by gluten, which is found in wheat, rye, and barley. The observance coincides with the birthday of English physician Samuel Gee, who was the first to provide a comprehensive description of the disease and emphasized that a gluten-free diet is the only treatment. Celiac disease affects individuals who are genetically predisposed, leading to symptoms such as chronic diarrhea, abdominal distention, and malabsorption of nutrients. About 1 in 135 people are diagnosed with celiac disease, while many others experience non-celiac gluten sensitivity. The primary focus of National Celiac Disease Awareness Day is to inform the public about the importance of a gluten-free diet for those affected.