Common Causes of Bad Breath & Treatment Options

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Medically Reviewed
by Dr. Lara Coseo
Alyssa Hill
Written by
Alyssa Hill
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Evidence Based
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1 sources cited
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What is Halitosis (Bad Breath)?

Halitosis, which is the medical term for bad breath, affects about 40 million Americans in the United States. Bad breath is characterized by an unpleasant and persistent odor in exhaled breath that is typically not serious. There are a variety of causes of bad breath that are linked to poor dental hygiene, eating habits, or even dehydration.

The tongue also harbors bacteria, and if it is not brushed daily, halitosis can develop. In some cases, if halitosis persists even after brushing, it may be a sign of an underlying infection or disease.

Most people with chronic halitosis do not notice they have the condition. Although, licking the forearm and smelling it will typically indicate bad breath.

Halitosis also occurs less in vegetarians than meat-eaters. This is because if the mouth is not cleaned properly, leftover meat particles will begin to decay and produce a foul smell.

Risk Factors & Causes of Halitosis

The cause of bad breath could be linked to lifestyle habits, diet, poor dental care, or an individual’s medical history. Common risk factors include:

Poor Oral Hygiene

Mouth fresheners, gums, and sprays could help temporarily if used in between flossing, brushing, and rinsing with chlorine dioxide mouthwash. Chewing parsley, basil, mint, or cilantro also helps control bad breath.


Coffee is a highly acidic substance that can lead to dry mouth, tooth discoloration, and halitosis. However, rinsing with mouthwash, brushing, and flossing after drinking coffee reduces bad breath.


Alcoholic drinks and mouthwashes containing more than 25 percent alcohol can lead to halitosis.

Sugar and Processed Foods

Naturally occurring bacteria in the mouth feeds on sugars and results in a sour smell. So, you should eat a balanced diet to counteract the effects of unhealthy foods on your oral health and breath.

Smoking Tobacco

Cigarettes and other tobacco products, such as cigars and chewing tobacco, can cause bad breath and dry mouth. This is especially if your oral health is neglected as well.

Certain Medications

Blood pressure medications, such as beta-blockers, diuretics, alpha-blockers, and calcium channel blockers, can lead to halitosis. Antihistamines, tetracyclines, sulfa, antidepressants, and decongestants can also cause bad breath.

Dry Mouth

Dry mouth, also called xerostomia, is a non-life-threatening oral condition that occurs when the salivary glands in the mouth do not produce enough saliva to keep the mouth wet. It is caused by insufficient fluid intake and certain prescription medications. Cancer treatments, such as chemo, can also result in thick saliva, causing dry mouth.

Xerostomia naturally occurs while you are sleeping and typically causes bad breath in the morning. In particular, adults who sleep with their mouths open are more likely to develop dry mouth.


Low-carb diets (ketosis), fasting, and high-protein diets can cause halitosis. This includes eating excessive amounts of eggs, dairy, and red meat. Not eating enough carbohydrates can also cause this condition.


Dehydration, mucus build-up, and tonsil infections can cause bad breath. Hormonal changes in women, especially during pregnancy, can result in bad breath as well.

Treatment Options for Bad Breath

Halitosis typically goes away on its own with lifestyle changes and proper oral care. In particular, good oral care tips include:

Routine Dental Exams and Preventive Treatment

The American Dental Association (ADA) suggests that adults visit a dentist for regular exams and teeth cleanings at least twice a year (every six months). During dental exams, a dentist or dental hygienist examines the mouth for cavities, decay, gum disease, and other oral health conditions.

Preventing Bad Breath

Brushing twice a day, flossing at least once a day, and rinsing the mouth with an alcohol-free mouthwash regularly kills bacteria and keeps the mouth healthy. Brushing the tongue with a scraper also helps prevent bad breath.

Other halitosis prevention techniques and treatment options include:

  • Chewing Sugarless Gum (stimulates bacteria-fighting saliva).
  • Avoiding Toothpicks (they damage the gums and teeth).
  • Using anti-VSC Oral Care Products (they do not contain alcohol or zinc).
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