Researchers are just beginning to explore the gluten/casein/autism link. They are looking into it because so many families have claimed to see positive results in their autistic children when they them on this diet. It is not yet clear why the diet should help but in time, we'll probably have our answers. Meanwhile, I would suggest trying the diet with your child since there is no real downside. Gluten-free breads, pastas and pastries are readily available in regular supermarkets now so your child needn't suffer. There are lots of milk alternatives available, lots of allergy-free kid friendly cookbooks and lots of on-line support for gluten-free and food intolerant cooks. If you don't see results you can always go back to the old way. Keep in mind that every body is different and it may take a few months before you will see the total result of the diet switchover.  Good luck.  Sarah Chana