White tongue is usually from Candida. look up Dvjorge, Frostymug, they cured themselves by doing Nystatin retention enemas's. Clean diet, Cleaning your colon and Nystatin powder(sugar free) should do the trick. then once the Candida is under control you start adding high quality probiotics, and foods that feed your good bacteria like kefir, Saurkruat, Oatbran etc...