Bad Breath... The Causes

Causes for bad breath (halitosis) may be broadly classified into oral and extra-oral causes.

Oral causes:
* Gum disease
* Decayed teeth
* Oral ulcers
* Food impaction
* Poor denture hygiene
Drymouth (Xerostomia)
Extraoral causes:
*ENT & related conditions – Rhinitis, Sinusitis, Pharyngitis, Tonsillitis, Asthma,  
Bronchitis, Bronchiectasis
*GI Conditions – Acid Reflux, APD, Constipation
*Foods – garlic, onions etc., coffee
*Systemic diseases – Diabetes, Liver disease, Renal disease

Causes may be local or systemic. The local causes related to halitosis include wearing dentures or partial dentures, faulty dental fillings, drifted, moved or extruded teeth, gingivitis, gum or tooth abscesses, oral cancer and xerostomia or dry mouth.

The human being has over 400 species of different types of bacteria in the mouth of which about fourteen of them, mainly anaerobic bacteria, cause bad breath by releasing sulfur odors. Halitosis is caused by volatile sulfur compounds (VSC – mainly hydrogen sulfide and methyl mercaptan), which are released by the break down of proteins by bacteria. These sulfur compounds are odorous (rotten egg smell) and lousy tasting. Bad breath mostly comes from the back of the tongue, not the stomach or teeth. Most of the odor contributing to bad-breath is produced by anaerobic bacteria, which grow on the back of the tongue. Tongue cleaning reduces mouth odor by 75 percent. The anaerobic bacteria have beneficial effects also as they aid in digestion by breaking down proteins. Persons suffering from badbreath due to oral causes are found to have abnormally high numbers of anaerobic bacteria in the oral cavity. An agent called halimeter is used by some of the specialists which aids in measuring the concentration of sulphide molecules in breath of patients – which in turn gives an assessment about the degree of badbreath the patient has.

Systemic medical conditions contribute to a significant percentage of halitosis cases. Diseases afflicting the nose, sinuses, throat, lungs and the gastrointestinal system – the body parts which are anatomically linked to the mouth – are also found to contribute to halitosis. Eg. conditions like sinusitis, pharyngitis, common cold, bronchitis and asthma, tonsillitis, indigestion and acidity, constipation, etc. are found to cause bad breath. Persons suffering from colds and sinusitis often have postnasal drips of mucus which is rich in protein. Breakdown of the proteins by anaerobes cause release of VSCs causing the bad breath. Medical conditions such as diabetes, renal failure, liver dysfunction, hormonal imbalance etc. are also found to cause halitosis.

Food and tobacco are contributing factors to halitosis but are not a primary cause. Very spicy foods, such as onions and garlic (they contain sulfur compounds called mercaptans), and coffee may be detected on a person's breath for up to 72 hours after digestion. Onions, for example, are absorbed by the stomach and the odor is then excreted through the lungs. Studies even have shown that garlic rubbed on the soles of the feet can show up on the breath. There are 4 categories of food which are found to increase the problem of badbreath by causing an increase in sulfide production by bacteria – drying agents (cigarettes, alcohol), dense protein foods (diary foods, meat and fish) sugars and acids (coffee, fruit juices such as those of citrus, orange, tomato, grapes, pineapple etc.) – all these stimulate growth of anaerobic bacteria. Alcohol being dessicants (drying agents), can only worsen the bad breath. So is the case with alcohol based mouthwashes.

Even stress, dieting, snoring, age and hormonal changes can have an effect on your breath.

Morning breath - Saliva is the key ingredient in your mouth that helps keep the odor under control because it helps wash away food particles and bacteria, the primary cause of bad breath. When you sleep, however, salivary glands slow down the production of saliva allowing the bacteria to grow inside the mouth. To alleviate "morning mouth," brush your teeth and eat a morning meal. Morning mouth also is associated with hunger or fasting. Those who skip breakfast, beware because the odor may reappear even if you've brushed your teeth. Remaining still for long hours with restricted movement of the tongue and jaws such as while traveling long distances, slows down salivary production and will also be associated with bad breath due to the reasons mentioned above.