Try feeding high meat content foods and/or raw food diet i.e. a diet free of carbs (which are in all dry foods in some form or another, and many wet foods in the form of cereals). Nature's Harvest (I get mine from PAH), Forthglade (I get from local pet shop), Bozita (online) are all high meat/no grain (carb). Applaws/Encore contain rice, but reasonably low amount, about 1% - although bear in mind its not complete so you shouldnt feed it everyday but mix n match with other complete diets.