Halitosis is the technical term for bad breath, a condition estimated to affect 50 to 65% of the population.1
Up to 90% of cases are thought to originate from sources in the mouth, including poor oral hygiene, periodontal disease, coating on the tongue, impacted food, faulty dental restorations, and throat infections.2 3 4 The remaining 10% are due to systemic disorders, such as peptic ulcer (when associated with infection),5 6 lung infections (bad breath can be the first sign in some cases),7 liver or kidney disease,8 9 diabetes mellitus, cancer,10 or even a person’s imagination (healthy individuals sometimes complain of bad breath that cannot be smelled by anyone else and is not linked to any clinical disorder).11
In most cases, bad breath in the mouth can be traced to sulfur gases produced by bacteria in the mouth.12 13 Factors that support the growth of these bacteria will predispose a person to halitosis. Examples include accumulation of food within pockets around the teeth,14 among the bumps at the back of the tongue,15 or in small pockets in the tonsils; sloughed cells from the mouth; and diminished saliva flow. Mucus in the throat or sinuses can also serve as a breeding ground for bacteria. Conditions are most favorable for odor production during the night and between meals.16
Although bad breath primarily represents a source of embarrassment or annoyance, research has shown that the sulfur gases most responsible for halitosis (hydrogen sulfide and methyl mercaptan) are also potentially damaging to the tissues in the mouth, and can lead to periodontitis (inflammation of the gums and ligaments supporting the teeth).17 18 As periodontal disease progresses, so may the halitosis, as bacteria accumulate in the pockets that form next to the teeth.
Lifestyle changes that may be helpful for halitosis
Home oral hygiene is probably the most effective way to reduce accumulations of debris and bacteria that lead to halitosis. This includes regular tooth brushing and flossing, and/or the use of mechanical irrigators to remove accumulations of food after eating. Brushing the tongue or using a commercial tongue scraper, especially over the bumpiest region of the tongue, may help remove the odor-causing agents as well as lower the overall bacteria count in the mouth.
Because of the role of gum disease in halitosis, regular dental care is recommended to prevent or treat gum disease. Treatment for a person with periodontal pockets might include scaling of the teeth to remove tartar.19
A reduced saliva flow increases the concentration of bacteria in the mouth and worsens bad breath.20 One of the most common causes of dry mouth is medication, such as antihistamines, some antidepressants, and diuretics; however, chronic mouth breathing, radiation therapy, dehydration, and various diseases can also contribute.21 Measures that help increase saliva production (e.g., chewing sugarless gum and drinking adequate water) may improve halitosis associated with poor saliva flow. Avoiding alcohol (ironically found in many commercial mouthwashes) may also help, because alcohol is drying to the mouth.
Access by oral bacteria to sulfur-containing amino acids will enhance the production of sulfur gases that are responsible for bad breath. This effect was demonstrated in a study in which concentrations of these sulfur gases in the mouth were increased after subjects used a mouth rinse containing the amino acid cysteine.22 Cleaning the mouth after eating sulfur-rich foods, such as dairy, fish, and meat, may help remove the food sources for these bacteria.
Nutritional supplements that may be helpful for halitosis
Because most halitosis stems from bacterial production of odiferous compounds, general measures to diminish bacteria as well as measures targeted at prevention or treatment of periodontitis and gingivitis may be helpful. Mouthwashes or toothpastes containing a compound called stabilized chlorine dioxide appear to help eliminate bad breath by directly breaking down sulfur compounds in the mouth. One study showed reductions in mouth odor for at least four hours following the use of a mouthrinse containing this substance.23
Preliminary research has also demonstrated the ability of zinc to reduce the concentration of volatile sulfur compounds in the mouth. One study found that the addition of zinc to a baking soda toothpaste lessened halitosis by lowering the levels of these compounds.24 A mouthrinse containing zinc chloride was seen in another study to neutralize the damaging effect of methyl mercaptan on periodontal tissue in the mouth.25 26
Nutritional supplements recommended by some doctors for prevention and treatment of periodontitis include vitamin C (people with periodontitis are often found to be deficient),27 vitamin E, selenium, zinc, coenzyme Q10, and folic acid.28 Folic acid has also been shown to reduce the severity of gingivitis when taken as a mouthwash.29
Are there any side effects or interactions with halitosis?
Refer to the individual supplement for information about any side effects or interactions.
Herbs that may be helpful for halitosis
The potent effects of some commercial mouthwashes may be due to the inclusion of thymol (from thyme) and eukalyptol (from eucalyptus)—volatile oils that have proven activity against bacteria. One report showed bacterial counts plummet in as little as 30 seconds following a mouthrinse with the commercial mouthwash Listerine™, which contains thymol and eukalyptol.30 Thymol alone has been shown in research to inhibit the growth of bacteria found in the mouth.31 32 Because of their antibacterial properties, other volatile oils made from tea tree,33 clove, caraway, peppermint, and sage,34 as well as the herbs myrrh35 and bloodroot,36 might be considered in a mouthwash or toothpaste. Due to potential allergic reactions and potential side effects if some of these oils are swallowed, it is best to consult with a qualified healthcare professional before pursuing self-treatment with volatile oils that are not in approved over-the-counter products for halitosis.
Are there any side effects or interactions with halitosis?
Refer to the individual herb for information about any side effects or interactions.