Tonsillitis, respiratory infections such as sinusitis or bronchitis, and some gastrointestinal diseases may be responsible for a small number of cases of bad breath. Advanced liver or kidney disease and uncontrolled diabetes can also cause unpleasant breath. Halitosis, or bad breath, is mainly caused by sulfur-producing bacteria that live on the surface of the tongue and in the throat. These bacteria can break down proteins at a high rate, releasing odorous volatile sulfur compounds (VSCs) from the back of the tongue and throat.
It is estimated that around 2.4% of adults suffer from bad breath. A diet high in sugar can also be a cause of bad breath, as sugars interact with existing bacteria in the mouth. If you are unsure if you have bad breath, it is best to ask a close friend or family member to confirm your suspicions. Bad breath, also known as oral odor or halitosis, is a very common and treatable condition in many adults.
Poor oral hygiene is usually the main cause of bad breath, but other situations can also be to blame. To diagnose halitosis, a dentist will smell the breath of a person suspected of having it and rate the smell on a six-point intensity scale. Poor oral hygiene can also lead to other oral health conditions such as tooth decay and gum disease, which are also associated with bad breath. Some people worry too much about their breath even though they have little or no smell in their mouths, while others have bad breath and don't know it.
The main symptom of halitosis is an unpleasant smell from the mouth that is considered to be beyond a socially acceptable level.