Unpleasant odors on the breath are referred to as halitosis: these may be produced by diet, and are often only temporary after consumption of such items as liquor, onions garlic, various spices, wines, etc.
The degree to which halitosis is found objectionable varies with different groups; furthermore, if everyone partakes of the offending item, no one complains. Thus smokers generally have no objection to “tobacco breath,” though non-smokers may complain. Poor mouth hygiene is sometimes a cause of halitosis and may require more frequent brushing of the teeth, perhaps combined with the use of dental floss or other cleansing techniques. Dentures should not be worn continuously and require cleaning from time to time.
Disordered digestion and certain conditions of the nose or respiratory passages may also make the breath odorous. The doctor will direct treatment to the underlying cause in these instances. Where the cause of an offensive odor cannot be tracked down or treated, a masking scent may be the only practical suggestion. Mints and similar items are, of course, widely used for such purposes.