Bad breath, also known as halitosis or fetor oris, affects an estimated 25% of people, globally. There are a number of potential causes of halitosis but the vast majority come down to oral hygiene.
Halitosis can cause significant worry, embarrassment and anxiety but, generally, it is relatively easy to remedy.
In this article, we will discuss the potential origins of bad breath, diagnosis and how to treat it.
Contents of this article:
Here are some key points about bad breath. More detail and supporting information is in the main article.
- Bad breath is estimated to affect 1 in 4 people globally
- The most common cause of halitosis is bad oral hygiene
- If particles of food are left in the mouth, their breakdown by bacteria produces sulfur compounds
- There are a number of common causes of bad breath, including smoking, tooth decay and alcohol consumption
- Keeping the mouth hydrated can reduce mouth odor
- Bad breath in children is often due to a trapped item in the nasal cavity
- Rarer causes of bad breath include bowel obstruction, ketoacidosis and aspiration pneumonia
- The best treatment for bad breath is regular brushing, flossing and hydration
- Crash diets can cause bad breath because of the build-up of ketones.
What is halitosis?
Although bad breath is associated with certain diseases, oral hygiene is the most common cause.
Bad breath is a common problem that can cause significant psychological distress. There are a number of potential causes and treatments available.1
Anyone can suffer from bad breath; it is estimated that 1 in 4 people have bad breath on a regular basis.2
Halitosis is the third most common reason that people seek dental care (after tooth decay and gum disease).3
The most common cause of bad breath is poor dental hygiene. As bacteria break down particles of food, sulfur compounds are produced that cause odor.4
Simple home remedies and lifestyle changes, such as improved dental hygiene and quitting smoking, can often remove the issue. If bad breath persists, however, it is advisable to visit a doctor to check for underlying causes.
Symptoms of halitosis
The specific odor of breath can vary depending on the cause of the problem. It is best to ask a close friend or relative to gauge your mouth odor as it is very difficult to assess it yourself.
If no one is to hand, one way of checking the odor is to lick your wrist, leave it to dry and then smell it. If it smells bad, there is a strong chance your breath also smells bad.
Some individuals are concerned about their breath even though they may have little or no mouth odor; this condition is called halitophobia and can lead to obsessive mouth-cleansing behavior.
Causes of bad breath
One of the major factors involved in bad breath is cigarette smoke.
Potential causes of bad breath include:
- Tobacco: tobacco products cause their own types of mouth odor. Additionally, they increase the chances of gum disease which can also cause bad breath
- Food: the breakdown of food particles stuck in the teeth can cause odors. Some foods such as onions and garlic can also cause bad breath. After they are digested, their breakdown products are carried in the blood to the lungs where they can affect the breath
- Dry mouth: saliva naturally cleans the mouth. If the mouth is naturally dry (for instance, in the morning) or is dry due to a specific disease (such as xerostomia), odors can build up
- Dental hygiene: brushing and flossing ensure the removal of small particles of food that can build up and slowly break down, producing odor. A film of bacteria called plaque builds up if brushing is not regular. This plaque can irritate the gums and cause pockets of build-up between the teeth and gums called periodontitis. Dentures that are not cleaned regularly or properly can also harbor bacteria that cause halitosis
- Crash diets: fasting and low-carbohydrate eating programs can produce halitosis; this is due to the breakdown of fats producing chemicals called ketones. These ketones have a strong aroma
- Drugs: certain medications can reduce saliva and, therefore, increase odors. Other drugs can produce odors as they breakdown and release chemicals in the breath. Examples include nitrates used to treat angina, some chemotherapy chemicals and some tranquilizers, such as phenothiazines. Individuals who take vitamin supplements in large doses can also be prone to bad breath
- Mouth, nose and throat conditions: sometimes small, bacteria covered stones can form on the tonsils at the back of the throat (tonsilloliths) and produce odor. Also, infections or inflammation in the nose, throat or sinuses can cause halitosis
- Foreign body: bad breath (especially in children) can be caused if they have a foreign body lodged in their nasal cavity
- Diseases: some cancers, liver failure and other metabolic diseases can cause halitosis due to specific mixes of chemicals that they produce. Gastroesophageal reflux disease (GERD) can cause bad breath due to the regular reflux of stomach acids.
Rarer causes of bad breath
As mentioned earlier, the most common reason for bad breath is oral hygiene, but other situations can also be to blame.
Rarer causes of bad breath (halitosis) include:
- Ketoacidosis: when the insulin levels of a person with diabetes are very low, their bodies can no longer use sugar and begin to use fat stores instead. When fat is broken down, ketones are produced and build up. Ketones can be poisonous when found in large numbers and produce a distinctive and unpleasant breath odor. Ketoacidosis is a serious and potentially life-threatening condition5
- Bowel obstruction: breath can smell like feces if there has been a prolonged period of vomiting, especially if a bowel obstruction is present
- Chronic kidney failure: an odor similar to ammonia or urine has been noted in patients with chronic kidney failure. Waste products normally removed by the kidneys are left to build up in the bloodstream6
- Bronchiectasis: a long-term condition where airways are wider than normal, allowing for a build-up of mucus that leads to bad breath7
- Aspiration pneumonia: a swelling or infection in the lungs or airways due to inhaling vomit, saliva, food or liquids.
Diagnosis of halitosis
Often, a dentist will simply smell the breath of a patient and rate the odor on a six-point intensity scale. The dentist may scrape the back of the tongue and smell the scrapings as this area can often be a source of the aroma.
There are a variety of sophisticated detectors that can rate odor more precisely, they include the following:
- Halimeter: detects low levels of sulfur
- Gas chromatography: measures three volatile sulfur compunds - hydrogen sulfide, methyl mercaptan and dimethyl sulfide
- BANA test: measures for a specific enzyme produced by halitosis-causing bacteria
- Beta-galactosidase test: levels of the enzyme beta-galactosidase have been found to correlate with mouth odor.
Treatment for bad breath
Oral hygiene is the key to most bad breath issues.
The best method to reduce halitosis is good oral hygiene; it ensures that cavities are avoided and reduces the likelihood of gum disease.
It is recommended that individuals visit the dentist for a check-up twice a year.
The dentist may recommend a toothpaste that includes an antibacterial agent or an antibacterial mouthwash.
Alternatively, if gum disease is present, professional cleaning may be necessary to clear out the build-up of bacteria in pockets between the gums and teeth.
Other lifestyle and home remedies for bad breath include:
- Brush teeth: brush at least twice a day, but preferably after each meal
- Floss: flossing reduces the build-up of food particles and plaque from between the teeth - brushing only cleans around 60% of the surface of the tooth
- Clean dentures: anything that goes into your mouth - dentures, bridge, mouth guard - should be cleaned as recommended on a daily basis. Cleaning prevents the bacteria from building up and being transferred back into the mouth. Changing toothbrush every 2-3 months is also important for similar reasons
- Brush tongue: bacteria, food and dead cells commonly build up on the tongue, especially in smokers or those with a particularly dry mouth. Sometimes, a tongue scraper can be useful
- Avoid dry mouth: drink plenty of water. Avoid alcohol and tobacco, both of which dehydrate the mouth. Chewing gum or sucking a sweet (preferably sugar-free) can help stimulate the production of saliva. If the mouth is chronically dry, a doctor may prescribe medication that stimulates the flow of saliva
- Diet: avoid onions, garlic and spicy food. Sugary foods are also linked to bad breath. Reduce coffee and alcohol consumption. Eating a breakfast that includes rough foods can help clean the back of the tongue.
If breath odor persists despite the factors listed above being under control, it is recommended that an individual visits a doctor for further tests to rule out other conditions.
A comparison of acidity levels in the mouths of individuals who did and did not breathe through the mouth during sleep finds mouth breathing may promote dental erosion and decay.
Research published this week in the Annals of the American Thoracic Society demonstrates that a diet high in fiber might reduce the chance of developing lung disease - yet another reason to eat healthily.