Bad Breath (Halitosis) - Bad breath coming from the mouth

Bad breath coming from within the mouth

In most people who have bad breath (halitosis), the bad smell is thought to come from germs (bacteria) and debris within the mouth. As the bacteria break down proteins and other debris in the mouth, they release foul-smelling gases. One or more of the following may contribute to the build-up of bacteria, debris and bad breath:

  • Food stuck between teeth. Normal teeth brushing may not clear bits of food which can get stuck between teeth. The food then rots and becomes riddled with bacteria. Regular cleaning between the teeth can clear and prevent this problem.
  • Plaque, tartar (calculus) and gum disease. Dental plaque is a soft whitish deposit that forms on the surface of teeth. It forms when bacteria combine with food and saliva. Plaque contains many types of bacteria. Calculus is hardened calcified plaque. It sticks firmly to teeth. Gum disease means infection or inflammation of the tissues that surround the teeth. If your gums look inflamed, or regularly bleed when you clean your teeth, you are likely to have gum disease. The severity can range from mild to severe.
  • Coating on the back of the tongue. In some people, a coating develops on the back part of the tongue. It is not clear why this occurs. It may be from mucus that drips down from the back of the nose (postnasal drip). The coating can contain many bacteria. This explains why bad breath can sometimes occur in people with otherwise good oral hygiene.
  • Tonsil stones (tonsilloliths). These are clusters of calcified material that form in the tonsillar crypts, or crevices of the tonsils. They are made up mostly of calcium but can contain other ingredients such as magnesium and phosphorus, and can feel like a small lump in the tonsils. Rarely harmful, they can be a nuisance and hard to remove and can often cause bad breath.

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Author:
Dr Mary Harding
Peer Reviewer:
Dr Helen Huins
Document ID:
4892 (v43)
Last Checked:
06 July 2017
Next Review:
05 July 2020

Disclaimer: This article is for information only and should not be used for the diagnosis or treatment of medical conditions. Patient Platform Limited has used all reasonable care in compiling the information but make no warranty as to its accuracy. Consult a doctor or other health care professional for diagnosis and treatment of medical conditions. For details see our conditions.