Bad breath is usually brought on by the breakdown of proteins by bacteria somewhere in the mouth. However, there are several other possible causes that affect the airways, oesophagus and stomach that can also lead to bad breath.
Bad breath, medically called halitosis, can result from poor dental health habits and may be a sign of other health problems. Bad breath can also be made worse by the types of foods you eat and other unhealthy lifestyle habits. People of any age may have halitosis.
Researchers have determined that bad breath typically begins when the waste produced by bacteria in the mouth, nose or stomach comes into contact with the air.
There are numerous nasal triggers for bad breath. Nasal dysfunction, including a genetic abnormality in the nasal passage, may inhibit proper mucus flow. The bacteria found in sinusitis, post-nasal drip and allergies may pass from the nose to the back of the tongue where it can lie dormant due to improper saliva flow or poor dental hygiene.
When bacterial plaque is not removed from the teeth, the gums or between the teeth, it continues to grow and ultimately may lead to halitosis, tooth decay and gum disease
Some types of bad breath are considered to be fairly normal. They usually are not health concerns. One example is “morning mouth.” This occurs because of changes in your mouth while you sleep. During the day, saliva washes away decaying food and odors. The body makes less saliva at night. Your mouth becomes dry, and dead cells stick to your tongue and to the inside of your cheeks. When bacteria use these cells for food, they produce a foul odor.