When parents decide to "do diet," they typically begin with GFCF. Keto CompleteThere are many good books about it, and the food marketplace is increasingly GFCF friendly. This diet entails the removal of all gluten and/or casein containing foods. Gluten is the protein found in wheat, rye, barley, spelt, kamut, and commercial oats, and casein, the protein found in dairy.