Halitosis is the technical term for bad breath, a condition estimated to affect 50 to 65% of the
population.1
Up to 90% of cases are thought to originate from sources in the mouth, including poor oral hygiene, periodontal disease, coating on the tongue, impacted food, faulty dental
restorations, and throat infections.2, 3, 4 The remaining 10% are due to systemic disorders,
such as peptic ulcer (when associated with infection),5, 6 lung infections
(bad breath can be the first sign in some cases),7liver or kidney disease,8, 9diabetes mellitus,
cancer,10 or even a person’s imagination (healthy individuals sometimes complain of bad
breath that cannot be smelled by anyone else and is not linked to any clinical disorder).11
In most cases, bad breath in the mouth can be traced to sulfur gases produced by bacteria in the
mouth.12, 13
Factors that support the growth of these bacteria will predispose a person to halitosis. Examples include
accumulation of food within pockets around the teeth,14 among the
bumps at the back of the tongue,15 or in small pockets
in the tonsils; sloughed cells from the mouth; and diminished saliva flow. Mucus in the throat or sinuses can
also serve as a breeding ground for bacteria. Conditions are most favorable for odor production during the
night and between meals.16
Although bad breath primarily represents a source of embarrassment or annoyance, research has shown that
the sulfur gases most responsible for halitosis (hydrogen sulfide and methyl mercaptan) are also potentially
damaging to the tissues in the mouth, and can lead to periodontitis
(inflammation of the gums and ligaments supporting the teeth).17, 18 As periodontal disease progresses, so may the halitosis, as bacteria accumulate in the pockets
that form next to the teeth.