The stomach is another possible cause of bad breath. Acid reflux (heart burn) is a growing problem and bad breath may be a warning sign. Do you lose your voice easily, have trouble swallowing at times, have chest pain? Have you started getting a lot of cavities after years with no cavities? See your doctor. Even more importantly, change your lifestyle. Give up junk food and get as much fat out of your diet as possible. Try altering your food intake for a month and see if your breath (and the reflux) improve. For more dietary information, I like www.drmcdougall.com.