Final answer:
A nurse should recommend a gluten-free diet to the parent of a child with celiac disease, avoiding foods that contain wheat, barley, and rye to prevent damage to the small intestine.
Step-by-step explanation:
When teaching the parent of a school-age child with celiac disease, the nurse should recommend a gluten-free diet. Celiac disease is an autoimmune disorder where the ingestion of gluten leads to damage in the small intestine, specifically to the microvilli which are crucial for nutrient absorption. Foods containing wheat, barley, and rye trigger this harmful immune response and should be completely avoided. Gluten-free foods do not contain these proteins and are safe for individuals with celiac disease, preventing symptoms such as malnutrition, cramping, and diarrhea. Restaurants that offer gluten-free options and reading food labels carefully are important practices for managing the disease.