Brush the teeth well and floss regularly. Cleanse the colon. Bad breath is often caused by toxins stored in the large intestine. To cover odor, eat parsley, drink peppermint tea, chew cloves, take chlorophyll, or gargle with barberry tea. Take acidophilus or chew uemboshi plums to improve intestinal flora. To insure proper digestion, chew food well, and drink water in between meals. Calcium, B-complex and C vitamins and the herb myrrh can prevent bad breath when taken daily.