Halitosis , colloquially called bad breath , is a
symptom in which a noticeably unpleasant odor is
present on the exhaled breath. Concern about
halitosis is estimated to be the third most
frequent reason for people to seek dental care,
following tooth decay and periodontal disease
(gum disease), and about 20% of the general
population are reported to suffer from it to some
Halitosis is caused due to breakdown of food
particles, saliva, blood or cells by bacteria. Most
of the cases are caused by poor oral hygiene .
Dental caries, mouth ulcers and mouth cancer are
other oral causes of halitosis. Halitosis is also
frequently caused by nose and throat infections.
Other conditions like lung infections, fever, liver
and kidney failure can also result in halitosis.
Improving oral hygiene with regular brushing of
teeth, cleaning of tongue and using mouthwashes
can help to improve halitosis. In some cases,
treatment of the underlying cause of halitosis
results in a cure.
‘More than 90 million people suffer from chronic
halitosis or bad breath. In most cases it
originates from the gums and tongue.’ (Source:
Some patients suffer from halitephobia. These
patients have the delusion that they suffer from
bad breath when it is not actually present. They
get obsessed with cleaning their mouth repeatedly
with mouthwashes and keep using chewing gums
and mints. They also try to keep their distance
from others and avoid social interactions. These
patients require psychological support.
Very rarely, halitosis can be one of many
symptoms of a serious underlying medical
condition such as liver failure , but in the vast
majority of cases the cause is minor and can
often be reduced by adjustments to oral hygiene ,
including brushing or gently scraping the back of
the tongue and improving the health of the gums,
e.g. by using dental floss . Occasionally however,
especially if the origin of the odor is not in the
mouth, halitosis can be more difficult to diagnose
and to manage successfully. Bad breath is a
social taboo and, as a result, perceived or
genuine halitosis can sometimes trigger social
anxiety and depression.
Causes and Diagnosis
Poor oral hygiene is the most common cause of
halitosis. However, a person may suffer from
halitosis due to other conditions as well.
Halitosis or bad breath is caused by diseases
affecting the mouth and sometimes nose or
throat. Bacteria present in the mouth act on food
particles, saliva, cells or blood in the mouth to
produce halitosis. Some causes of halitosis
Poor oral hygiene : Poor oral hygiene leads to
accumulation of food and plaque in the mouth.
These result in inflammation of gums called
gingivitis and of the tissues surrounding the teeth
called peridontitis. Both gingivitis and peridontitis
can cause halitosis. A particular type of gingivitis
called Vincent’s disease or trench mouth causes
very bad halitosis. Besides, dental caries also
lead to oral malodor.
Dry mouth or Xerostomia : Dryness of mouth
could occur in various conditions like Sjogren’s
Mouth ulcers: Bacteria can grow on the tissue
debris and blood of mouth ulcers and cause bad
Dentures : Dentures may increase tongue coat
deposits and lead to halitosis.
Morning halitosis: Halitosis that occurs when one
wakes up from sleep is called “morning
halitosis.” This could occur due to a nose or
throat infection or due to hot, dry surroundings.
Food and addictions : Foods like garlic, onions and
spices result in transient bad breath. Tobacco,
alcohol and betel nut could also cause halitosis.
Respiratory tract infections: Infections of the
upper respiratory tract like rhinitis, sinusitis and
tonsillitis as well as lung infections like
bronchiectasis can result in halitosis.
Cancer: Cancer of the mouth as well as of the
lungs can cause in bad breath.
Gastro-esophageal reflux disease : In
gastroesophageal reflux disease, the stomach
contents move back into the esophagus and
damage the lining of the esophagus. Bacteria
grow on these damaged portions and cause
Other conditions : Conditions like fever, diabetes,
liver and kidney failure result in halitosis.
Fish Odor Syndrome : Fish Odor Syndrome or
Trimethylaminuria is a genetic disorder where the
patient’s mouth and body smell of rotten fish.
Halitosis is diagnosed using the organoleptic
procedure. Improving oral hygiene often helps to
cure the condition.
Halitosis is diagnosed by the presence of malodor
or bad breath. Smelling the air from the mouth
and nose separately and comparing the intensity
of the two odors using the organoleptic procedure
helps to diagnose the origin of the problem. Odor
from both the mouth as well as the nose of
similar intensity indicates that the problem is not
a local one.
Though some tests like gas chromatography (GC)
and sulphide monitoring are available to test
what the malodor is due to, they are expensive
and usually not practical to be carried out.