Bad Breath (Halitosis)

Bad Breath (Halitosis): Overview

Alternative names: Oral Malodor, Halitosis

Most people will suffer from some degree of bad breath at some time in their lives.

Diagnose your symptoms now!
  • understand what's happening to your body
  • have a doctor review your case (optional)
  • learn what you should be doing right now

Contrary to popular belief, we cannot smell our own breath because we become accustomed to our own smell.

Causes and Development

Bad breath is a common problem that can be due to many causes.  Only in rare cases do stomach or digestive problems contribute to bad breath.  Most bad breath comes from the back of the mouth.

Temporary bad breath most commonly comes from the foods we eat such as onions, garlic and cabbage which will produce high amounts of sulfur compounds.  The digested sulfur compounds are absorbed and carried by blood into the lungs where they are exhaled to produce bad breath.  However, chronic bad breath is most commonly caused by bacteria that break down food debris left in the mouth.

Common Causes of Bad Breath:

  • Odor-causing foods.  Most commonly, the smell is a result of breakdown of proteins by various bacteria in the mouth.  For example, volatile sulfur compounds and other substances like cadaverine and putrescine are produced by certain anaerobic bacteria .  Foods including garlic, onions and some spices as well as tea and coffee can contribute towards bad breath.
  • Tooth decay or periodontal (gum) disease.  Gum disease and tooth decay will often lead to accumulations of bacteria that can cause bad breath.  If there is gum disease or tooth decay, then treatment should be sought to eliminate these problems first.  Your dentist will examine you and take some radiographs (X-rays) to check for the presence and extent of such problems.  Early detection, diagnosis and treatment of gum disease and tooth decay will help keep teeth functional for life.  Preventive maintenance is essential to ensure continued good oral health.
  • Prolonged mouth dryness
  • Use of tobacco products
  • Sinus or respiratory infections
  • Inadequate oral hygiene.  Poor oral hygiene from infrequent brushing of teeth or cleaning of dentures will lead to food debris left in the mouth, around teeth, on dentures, tongue and cheek surfaces, which will be broken down by bacteria resulting in unpleasant breath.
  • Medications e.g. anti-depressants, diuretics (used for high blood pressure)
  • Medical disorders e.g. esophageal-gastro reflux, chronic tonsil infections
  • Certain bacteria that produce foul-smelling compounds.  The bad smell can also come from the back of the surface of the tongue.  The scraping obtained by the dentist from this portion of the tongue may suggest that this may be the primary source of bad breath in the individual.  In such cases, it will help to use a tongue scraper daily to clean the tongue surface and reduce and prevent the accumulation of bacteria and foul-smelling, bacterial products.

Possible causes of various problems:

Problem: Odor after fasting, dieting, prolonged speaking, exercise, sleeping or taking medications.
Possible Cause: Dryness in the mouth caused by insufficient saliva flow.

Problem: Gums that bleed and bad breath.
Possible Cause: Gum disease caused by poor cleaning between teeth.

Problem: Odor when talking.
Possible Cause: Postnasal drip onto back of tongue.

Problem: Small whitish stones with foul odor appearing on tongue.
Possible Cause: Tonsilloliths from crypts in tonsils.

Problem: Odor appears suddenly from mouth of young child.
Possible Cause: Onset of throat infection.

Problem: Odor in denture wearers.
Possible Cause: Dentures kept in mouth all night or not cleaned properly.

Problem: Odor from nose.
Possible Cause: Sinusitis, polyps, dryness, foreign body, hindered air or mucous flow.

Problem: Bad taste all day long.
Possible Cause: Poor oral hygiene, gum disease, excessive bacteria on tongue surface.

Diagnosis and Tests

The key to effective treatment and management of this condition is proper diagnosis.  Recent research has enabled dentists to understand the causes of bad breath and therefore treat it more effectively.  The main problem is accepting that one has bad breath as most individuals cannot smell their own breath.  Asking friends or seeking other's opinion is usually the best way.  Dentists usually begin by checking for the presence of oral disease or conditions that can contribute to bad breath.

Treatment and Prevention

Good brushing and flossing habits will help reduce bad breath.  However, most people do not brush their teeth properly as it takes nearly 3 minutes to do so and most spend 45-60 seconds.  Furthermore, bad breath can come from bacteria residing deep within crevices on the back of the tongue and thus a tongue scraper is required.

Mouthwashes will only provide temporary relief from bad breath.  In fact, most mouthwashes contain alcohol, which has a drying effect in the mouth allowing bacteria to grow better.  There are newer mouthwashes without alcohol as well as those which have compounds that react with and neutralize odor-causing volatile sulfur compounds produced by bacteria in the mouth.

The DOs and DON'Ts of bad breath

  • Visit your dentist and have your teeth cleaned regularly
  • Floss and clean between your teeth as advised by your dentist
  • Brush your gums and teeth using the proper technique
  • Practice regular cleaning of your tongue, either by scraping or brushing
  • Use an alcohol-free mouthwash regularly
  • Drink plenty of liquids
  • Chew sugar-free gum especially when your mouth feels dry.  Alternatives include parsley, mints, fennel seeds or dill seeds.
  • Clean your mouth after eating or drinking milk products, fish or meat
  • Keep your dentures clean and soak them overnight in antiseptic solution
  • Eat fibrous vegetables and fruits to stimulate saliva flow and reduce build-up of food particles.


  • Ignore the problem
  • Drink too much coffee
  • Let young children use mouthwash as they tend to swallow it
  • Rely solely on mouthwashes – instead, practice good oral hygiene and eating habits
  • Let your concern about bad breath affect your life adversely.

Signs, symptoms & indicators of Bad Breath (Halitosis):

Symptoms - Head - Mouth/Oral


Symptoms - Sleep

Mouth breathing while sleeping or often waking up with a dry mouth

Without sufficient saliva, oral bacteria are not washed away.  This often leads to bad breath.

Risk factors for Bad Breath (Halitosis):


Dental / Oral


Effects of a Low Carbohydrate Diet

The acetone resulting from a state of ketosis escapes through the lungs – giving Atkins Diet followers, for example, what one weight-loss expert calls "rotten-apple breath." [Health 19 (1996): p.102]  The other ketones have to be excreted by the kidneys.  In a study funded by Dr. Atkins himself, most of the people that could stick with the diet reported headaches and halitosis (bad breath).


Environment / Toxicity

Organ Health

Tonsil Stones

A medical study conducted in 2007 found a strong association between tonsilloliths and bad breath.  Among those with bad breath, 75% of the subjects had tonsilloliths while only 6% of subjects with normal breath had tonsilloliths.

Symptoms - Head - Mouth/Oral

Wearing clean/wearing dirty dentures all day or wearing dirty dentures while awake

Dentures tend to collect particles of food and form bacterial plaque and tartar deposits, which are ideal places for bacteria, fungi and viruses to hide.  These in turn can cause mouth infections, gum disease, decay of any remaining teeth, and bad breath.

Concerned or curious about your health?  Try The Analyst™
Symptom Entry
Symptom Entry
Full Explanations
Optional Doctor Review
Review (optional)

Bad Breath (Halitosis) suggests the following may be present:

Environment / Toxicity

Recommendations for Bad Breath (Halitosis):



Report by The Analyst™
Click to see sample report
Health problems rarely occur in isolation or for obvious reasons

Your body is a highly complex, interconnected system.  Instead of guessing at what might be wrong, let us help you discover what is really going on inside your body based on the many clues it is giving.

Our multiple symptom checker provides in-depth health analysis by The Analyst™ with full explanations, recommendations and (optionally) doctors available for case review and answering your specific questions.


Weak or unproven link: may be a sign or symptom of; may increase risk of; may suggest
Weak or unproven link:
may be a sign or symptom of; may increase risk of; may suggest
Strong or generally accepted link: often increases risk of
Strong or generally accepted link:
often increases risk of
Definite or direct link: is a sign or symptom of; increases risk of
Definite or direct link:
is a sign or symptom of; increases risk of
Definitely or absolutely counter-indicates: strongly contraindicates
Definitely or absolutely counter-indicates:
strongly contraindicates
May be useful: may help with
May be useful:
may help with
Very useful: is highly recommended for
Very useful:
is highly recommended for
We use cookies for traffic analysis, advertising, and to provide the best user experience