Although ASD is not caused by diet, there have been reports of some success in controlling certain symptoms using dietary interventions.

* Gluten / Casein Free Diet ? some individuals with ASD experience limited tolerance or allergies to certain foods especially the proteins gluten and casein, which are found in wheat, rye, oat, and dairy products. Parents and physicians have reported significant behavioral changes when these products were eliminated from the diets of allergy prone individuals on the spectrum. Eliminating gluten and casein from a diet can be challenging, often requiring the elimination of all prepared foods and the careful preparation of wheat, rye, oat, and dairy free meals and snacks. In addition, the diet must be strictly maintained for long-term effectiveness. However, some parents find that the benefits (i.e. ? behavioral changes) far outweigh the extra time and effort that it takes to maintain the diet. Continued research regarding allergies and ASD is still needed.

* Anti-Yeast Therapy ? some individuals with ASD appear to experience excessive yeast accumulations in their digestive systems. Some parents and physician have reported significant behavioral changes in individuals with ASD following anti-yeast therapy. The therapy includes the administration of probiotics such as nystatin and careful elimination of all fermented foods from the diet. Fermented foods that must be eliminated include in barley malt, vinegar, chocolate, pickles, soy sauce, beer, and aged cheeses.