85% of all cases of bad breath originate from the mouth! In addition, 10% of the problem can be found in the (E)NT region. The remaining 5% is situated by a number of common diseases.
The accepted idea that bad breath comes from the stomach is totally wrong!

you can almost never smell your own breath


Oral bacteria are the source of the odors. When certain types are available in large amounts in the mouth, than the problems start. These micro-organisms are located between the teeth, on the tongue dorsum and in the periodontal pockets. In all these places it is not only warm, but also humid and there is plenty of food available. The present malignant bacteria (with Latin names as Porphyromonas gingivalis and Treponema denticola) thereby produce various acids that can cause a bad taste. This, however, is an individual problem. After all, another person can not experience the “bad taste” in your mouth!

oral micro-organsims couse the problem

But besides acids, these “animals” also produce (sulfur) gases, such as hydrogen sulphide, mercaptans and substances such as putrescine and cadaverine!
When these products are released in the mouth and then exhaled, we speak of bad breath or halitosis! The more dry the mouth, the easier the gases can escape!



Tongue coating is the largest contributor to the breath odor. The tongue may have a yellow, brown or black coating. These are bacteria, food debris and desquamating epithelial cells. In addition, the tongue can be rough or grooved. This roughness or these grooves give extra shelter to the bacteria: ideal to produce their foul odors!

coating causes odors

Dental plaque between the teeth or in the gingival pockets is the other major component of mouth odor. Thus, gum diseases such as gingivitis (inflamed gums) and periodontitis (inflamed supporting tissue around the teeth) are strongly associated with bad breathing.

For more information about gingivitis and periodontitis (periodontics), please visit the website of Mondcentrum Dr. Bollen (www.parimplant.com).

periodontitis and halitosis go hand in hand

The throat and nose area plays in lesser extent a role in halitosis. In particular, the presence of the tonsils can be decisive. In these “sponges”, the same bacteria are located and produce similar odors as in the rest of the mouth. Sometimes these bacteria along with food and epithelial cells are emitted as small grains: tonsilloliths. These small clots smell very unpleasant.

tonsillolith in the tonsil

Furthermore, foreign objects in the nose (often in children) can cause an odor. Even thick mucus in the throat can also be populated with bacteria and smell bad.

Some specific diseases, give a particular smell. Diabetic patients often smell sweet out of their the mouth. Liver diseases, lung diseases and endocrine problems can be detected with the smell out of the mouth. Also all kinds of cancers can cause unpleasant mouth air: e.g. lung cancer provides a very bad breath.
Note that stomach problems play only in less than 0.5% of cases a role in bad breath! So a gastrointestinal examination (gastroscopy) is not directly needed to discover the cause of halitosis.

gastroscopy is seldom necessary