Causes of bad breath

What you eat affects the air you exhale. Certain foods, such as garlic and onions, contribute to objectionable breath odour. Once the food is absorbed into the bloodstream, it is transferred to the lungs, where it is expelled.

Brushing, flossing and mouthwash will only mask the odour temporarily. Odours continue until the body eliminates the food. People on a diet may develop unpleasant breath from infrequent eating.

If you do not brush and floss daily, particles of food remain in the mouth, collecting bacteria, which can cause bad breath. Food that collects between the teeth, on the tongue and around the gums can rot, leaving an unpleasant odour.

Dentures that are not cleaned properly can also harbour odour causing bacteria and food particles.

One of the warning signs of periodontal (gum) disease is persistent bad breath or a bad taste in the mouth. Periodontal disease is caused by plaque, the sticky, colourless film of bacteria that constantly forms on teeth. The bacteria produce toxins that irritate the gums. In the advanced stage of the disease, the gums, bone and other structures that support the teeth become damaged.

Bad breath is also caused by dry mouth (xerostomia), which occurs when the flow of saliva decreases.

Tobacco products cause bad breath, stain teeth, reduces one's ability to taste foods and irritate gum tissues. Tobacco users are more likely to suffer from periodontal disease and are at greater risk for developing oral cancer.

Bad breath may be the sign of a medical disorder, such as a local infection in the respiratory tract (nose, throat, windpipe, lungs), chronic sinusitis, postnasal drip, chronic bronchitis, diabetes, gastrointestinal disturbance, liver or kidney ailment.

Smoking or chewing tobacco-based products causes bad breath and can also stain teeth, irritate gum tissue, and exacerbate tooth decay.

Overnight, bacteria accumulate in the mouth, causing bad breath that is commonly referred to as 'morning breath.' Some people breathe through their mouth at night, which can cause dry mouth and worsen morning breath.