Most adults suffer from bad breath occasionally, although it may affect up to a quarter of adults on a regular basis.
Bad breath is usually brought on by the breakdown of proteins by bacteria somewhere in the mouth. However, there are several other possible causes that affect the airways, oesphagus and stomach that can also lead to bad breath.
In some cases, bad breath can be a sign of a significant general health problem, so it should not be ignored. However, the usual cause is oral, which can often be treated to resolve the problem.
As bad breath is almost always caused by a problem in the mouth, it is helpful to visit a dentist. But if no oral cause can be identified by the dentist, it is recommended that you see an experienced doctor who can further investigate the causes and manage your treatment.