Bad Breath


Bad BreathThe clinical name for this is Halitosis, and is used to describe unpleasant odours exhaled in breathing. Bad Breath has a significant impact, both personally and socially, on those who suffer from it, and is estimated to be the third-most-frequent reason for seeking a dental appointment, after tooth decay and gum disease.

In most cases (85–90%), bad breath originates in the mouth. The intensity of bad breath differs during the day, due to eating certain foods (such as garlic, onions etc.), obesity, smoking, and alcohol consumption. Because the mouth is exposed to less oxygen and is inactive during the night, the smell is usually worse upon awakening (we are all familiar with “morning breath”). Bad breath may be transient, often disappearing following eating, brushing your teeth, flossing, or rinsing with a mouthwash.

Bad breath may also be persistent (chronic bad breath), which is a more serious condition, affecting some 25% of the population to varying degrees. It can negatively affect the individual’s personal, social, and business relationships, leading to poor self-esteem and increased stress.

What causes it?


The most common location for (mouth-related) halitosis is the tongue. Tongue bacteria produce malodourous compounds and account for 80 to 90% of all cases of mouth-related bad breath. Large amounts of naturally occurring bacteria are often found at the back of the tongue, where they remain relatively undisturbed by normal activity. This part of the tongue is relatively dry and poorly cleansed, and bacterial populations can thrive on remnants of food deposits, dead epithelial cells, and postnasal drip.

Cleaning your tongue

The most common reason to clean your tongue is for the control of bad breath. Methods used against bad breath, such as mints, mouth sprays, mouthwash or chewing gum, may only temporarily mask the smells created by the bacteria on your tongue, but cannot cure bad breath because they don’t actually remove the source of the bad breath. In order to prevent the production of malodourous compounds, the bacteria on the tongue must actually be physically removed, as must the decaying food debris present on the rear areas of the tongue. Most people who clean their tongue use a tongue cleaner (tongue scraper), or a toothbrush. Specially designed tongue cleaners are a lot more effective (collecting and removing the bacterial coating) than toothbrushes (which merely spread the bacterial accumulations on the tongue and in the mouth).


The average mouth contains over 600 types of bacteria. Several dozen of these can produce high levels of bad smells when incubated in the laboratory. Other parts of the mouth may also contribute to the overall smell, but are not as common as the back of the tongue.

Gum Disease

There is some controversy over the role of periodontal diseases in causing bad breath. Whereas bacteria growing below the gumline (subgingival dental plaque) have a foul smell upon removal, several studies reported no statistical correlation between malodor and periodontal parameters.


The second major source of bad breath is the nose. In this occurrence, the air exiting the nostrils has a pungent odour that differs from the oral odour. Nasal odour may be due to sinus infections or foreign bodies.


In general, putrefaction from the tonsils is considered a minor cause of bad breath, contributing to some 3–5% of cases. Approximately 7% of the population suffer from small bits of calcified matter in tonsillar crypts called tonsilloliths that smell extremely foul when released and may cause bad breath.


The Cardia, which is the valve between the stomach and the oesophagus, may not close properly due to a Hiatus Hernia, allowing acid to enter the oesophagus and gases escape to the mouth. A Zenker’s diverticulum may also result in halitosis due to aging food retained in the esophagus.


The stomach is considered by most researchers as a very rare source of bad breath.

Systemic Diseases

There are a few systemic (non-oral) medical conditions that may cause bad breath, but these are extremely infrequent in the general population.


At the current time, chronic halitosis is not very well understood by most doctors and dentists, so effective treatment is not always easy to find. Six strategies have been suggested:

1. Gently cleaning the tongue surface twice daily is the most effective way to keep bad breath at bay; that can be achieved using a tongue cleaner or tongue brush/scraper to wipe off the bacterial biofilm, debris, and mucus. An inverted teaspoon may also do the job; a toothbrush should be avoided, as the bristles only spread the bacteria in the mouth, and grip the tongue, causing a gagging reflex. Scraping or otherwise damaging the tongue should be avoided, and scraping of the V-shaped row of taste buds found at the very back of the tongue should also be avoided. Brushing a small amount of antibacterial mouth rinse or tongue gel onto the tongue surface may further inhibit bacterial action.

2. Eat a healthy breakfast with rough foods which will help clean the back of the tongue.

3. Chewing Gum: Since dry-mouth can increase bacterial buildup and cause or worsen bad breath, chewing sugar-free chewing gum may help with the production of saliva, and thereby help to reduce bad breath. Chewing may help particularly when the mouth is dry, or when one cannot perform oral hygiene procedures after meals. This aids in provision of saliva, which washes away oral bacteria, has antibacterial properties and promotes mechanical activity which helps cleanse the mouth. Some chewing gums even contain special anti-odour ingredients. Chewing on fennel seeds, cinnamon sticks, mastic gum, or fresh parsley are common folk remedies.

4. Gargling right before bedtime with an effective mouthwash. Several types of commercial mouthwashes have been shown to reduce bad breath for hours in peer-reviewed scientific studies. Mouthwashes may contain active ingredients that are inactivated by the soap present in most toothpastes. Thus it is recommended to refrain from using mouthwash directly after toothbrushing with paste.

5. Maintaining proper oral hygiene, including daily tongue cleaning, brushing, flossing, and periodic visits to your dentist. Flossing is particularly important in removing rotting food debris and bacterial plaque from between the teeth, especially around the gumline. Dentures should be properly cleaned and soaked overnight in antibacterial solution.

6. Mouthwashes: Mouthwashes often contain antibacterial agents including cetylpyridinium chloride, chlorhexidine, zinc gluconate, essential oils, and chlorine dioxide. Zinc and chlorhexidine provide strong synergistic effect. They may also contain alcohol, which is a drying agent.

Related Pages:

1. Five causes of bad breath:

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