Bad breath is a persistent or frequently recurring unpleasant odor on the breath, known medically as halitosis. It is most often related to oral and dental care, but problems in other areas, such as the tonsils, sinuses, the area behind the nose and the stomach, can also cause it. This article looks at the topic from both a dental and an ear, nose and throat perspective.
What Is Bad Breath?
Most of the unpleasant odor on the breath comes from volatile sulfur compounds produced when bacteria in the mouth break down food debris, shed cells and proteins. These gases give off the characteristic smell resembling rotten eggs or cabbage. Bacteria collect most densely on the rough surface at the back of the tongue.
The odor noticed on waking in the morning is due to reduced saliva flow overnight and is considered normal; it disappears after brushing and breakfast. Odor after garlic, onions and certain spices is also temporary. Odor that lasts all day despite good oral care and is noticed by people nearby, however, is worth investigating.
Halitosis can occur at any age and is very common. In the vast majority of cases, about 80–90% according to various sources, the problem originates in the mouth. In a significant part of the remainder, the cause lies in the ear, nose and throat region. Systemic causes involving the stomach, lungs, liver, kidneys or diabetes are much less common.
Real and Perceived Bad Breath
Some people believe their breath smells bad even though no one around them notices any odor. This is called perceived bad breath (pseudohalitosis). When anxiety is high, the person may avoid social situations, chew gum constantly or cover their mouth while talking. If no real odor is found on examination, reassurance and, if needed, psychological support are recommended.
Causes of Bad Breath
Identifying the source of the odor correctly is the most important step toward successful treatment. The causes fall into three main groups.
Mouth and Dental Causes
- Irregular tooth brushing and food debris left between the teeth
- A white-yellowish coating of bacteria on the tongue
- Gum inflammation (gingivitis) and advanced gum disease that causes gum recession (periodontitis)
- Tooth decay, infected roots and dental abscesses
- Poorly cleaned dentures, bridges and buildup around braces
- Dry mouth, which can result from drinking too little water, mouth breathing, some medications (antidepressants, blood pressure and allergy medicines) and salivary gland disorders
- Smoking and alcohol use
Ear, Nose and Throat Causes
If odor continues despite good oral hygiene, the ear, nose and throat region should always be evaluated. The main causes in this area are:
- Cryptic tonsils and tonsil stones: The surface of the tonsils has small pockets called crypts. In some people these pockets are deep and wide, and shed cells, food debris and bacteria collect inside them, forming small, white-yellowish, cheese-like, foul-smelling lumps. These are called tonsil stones (tonsilloliths) and are among the most common ENT-related causes of bad breath.
- Chronic tonsillitis: Repeated infections can cause lasting changes in tonsil tissue and foul-smelling buildup.
- Sinusitis: Especially in long-standing (chronic) sinusitis, infected mucus collecting in the sinuses drains down into the throat and causes odor. Many people with chronic sinusitis complain of bad breath.
- Postnasal drip: Thick mucus constantly draining from the back of the nose into the throat is a good food source for bacteria. Allergic rhinitis and sinusitis are frequent causes.
- Nasal blockage: A deviated septum, enlarged turbinates or polyps force mouth breathing, which dries the mouth and worsens odor.
- Reflux: Stomach contents flowing back into the esophagus and the throat and voice box area can cause a sour taste and odor. The type that reaches the throat is called laryngopharyngeal reflux.
- A foreign object in the nose in children: This should be considered in children with a one-sided, foul-smelling nasal discharge.
Systemic Causes
Less commonly, uncontrolled diabetes (a fruity, acetone-like odor), kidney failure (an ammonia-like odor), liver disease and lung infections can also cause breath odor. Prolonged fasting and very low-carbohydrate diets can change breath odor too, through the formation of ketones in the body.
Symptoms of Bad Breath
People often cannot detect the odor on their own breath, because the nose becomes desensitized to smells it is constantly exposed to. As a result, the problem is usually noticed when someone close mentions it or from other people’s reactions. Bad breath is often accompanied by:
- A persistent bad, metallic or sour taste in the mouth
- A white or yellowish coating, especially at the back of the tongue
- Dry mouth, dry lips and a frequent need to drink water
- A catching or foreign-body sensation in the throat when swallowing
- Small, white, very foul-smelling lumps coming out of the mouth when coughing or clearing the throat
- Constant postnasal drip, nasal blockage and a feeling of pressure in the face
- Heartburn, acid regurgitation, morning hoarseness and frequent throat clearing
- Bleeding gums when brushing
These accompanying symptoms provide important clues about the source of the odor. For example, in someone who coughs up tonsil stones, the source is most likely the tonsils; in someone with constant postnasal drip and facial pain, sinus problems come to the forefront.
How Is Bad Breath Diagnosed?
Diagnosis begins with a detailed interview. Questions cover how long the odor has been present, whether it changes during the day, oral care habits, diet, smoking and alcohol use, medications and any other complaints. Avoiding strong-smelling foods such as garlic and onions the day before the visit, and scented mouthwash and gum on the morning of the visit, makes the assessment more accurate.
Patients traveling from abroad are encouraged to bring any previous test results, dental reports, imaging and a list of their medications to the appointment.
Assessing the Odor
The doctor can assess the odor directly by asking the patient to breathe out through the mouth and then through the nose. Odor that comes from the mouth but not the nose usually points to a source inside the mouth, while odor from the nose as well suggests the nose and sinuses. Some centers also use devices that measure sulfur compounds in the breath.
Dental and Oral Examination
The teeth, gums, tongue surface and any dentures are examined. If gum disease or decay is suspected, a dental evaluation is requested. Other investigations often prove fruitless unless oral causes have been ruled out first.
Ear, Nose and Throat Examination
Tonsil size, the depth of the crypts and whether stones have collected in them are assessed; if needed, the tonsil is pressed gently to look for buildup in the crypts. An endoscope, a thin instrument with a camera, is used to examine the inside of the nose, the sinus openings, the area behind the nose, the tongue base and the larynx. Redness and swelling in the larynx can be a clue to reflux. A CT scan may be requested if sinusitis is suspected. If a systemic illness is suspected, blood sugar, kidney and liver tests are done or the patient is referred to the relevant specialist.
Treatment of Bad Breath
Treatment should target the source of the odor. Products that only mask the odor bring temporary relief but do not solve the problem.
Oral Care
- Brush your teeth at least twice a day, especially before bed, with fluoride toothpaste for at least two minutes.
- Clean between your teeth every day with floss or an interdental brush.
- Gently clean the tongue surface, especially the back, with a tongue scraper or a soft brush. This simple step is one of the most effective ways to reduce bad breath.
- Remove and clean dentures every night to give the mouth a rest.
- Have regular dental checkups and professional cleaning, and get gum disease and cavities treated.
- Drink enough water during the day; sugar-free gum can help by increasing saliva flow.
Antibacterial mouthwashes, used on a doctor’s advice and for a limited time, can reduce the bacterial load. Keep in mind that alcohol-containing mouthwashes can dry the mouth.
Treating Ear, Nose and Throat Causes
For tonsil stones, the first step is gargling with warm salt water or a suitable mouthwash after meals, together with good oral hygiene. In patients who form stones often and have marked odor, cryptolysis procedures that shrink and flatten the tonsil crypts using laser or radiofrequency may be performed. In selected patients with chronic tonsillitis, or when other methods have not helped, tonsil removal (tonsillectomy) may be considered.
For odor related to sinusitis, saline nasal rinses, steroid nasal sprays and, when needed, antibiotics are used. Endoscopic sinus surgery may be considered for chronic sinusitis that does not respond to medication. If allergic rhinitis is present, allergy treatment is adjusted. A deviated septum or enlarged turbinates causing nasal blockage can be corrected to reduce mouth breathing.
For suspected reflux, recommendations include avoiding late and heavy meals, leaving at least two to three hours between the last meal and bedtime, raising the head of the bed and cutting down on coffee, alcohol and acidic and fatty foods. When needed, acid-reducing medication is used and follow-up may be shared with a gastroenterologist.
Possible Risks and Important Considerations
Bad breath usually has a harmless cause, but it can significantly affect social relationships and self-confidence. Some self-treatments, however, may create new problems instead of solving the old one:
- Trying to remove tonsil stones with toothpicks, cotton swabs or hard objects can injure the tonsils and cause bleeding.
- Long-term, unsupervised use of antiseptic mouthwash can disturb the normal balance of mouth bacteria and stain the teeth.
- Constantly masking the odor with mints or gum can delay diagnosis of underlying gum disease or sinusitis.
See an ENT specialist without delay if the odor is accompanied by a mouth sore that has not healed after two to three weeks, enlargement of one tonsil only, difficulty swallowing, blood-streaked phlegm, unexplained weight loss, persistent hoarseness or a one-sided, foul-smelling nasal discharge.
Bad Breath: Frequently Asked Questions
Does bad breath come from the stomach?
Breath odor from the stomach is less common than people think. Most odor originates in the mouth. However, in some people with reflux, it may contribute to a sour taste and odor; in this case, treating the reflux can ease the symptoms.
Why do tonsil stones form, and do they go away on their own?
Tonsil stones form when food debris, cells and bacteria collect and harden in deep tonsil pockets. Small stones may fall out on their own with coughing or gargling, but if the crypts are deep, they tend to form again.
Will removing my tonsils cure bad breath?
If the source is tonsil stones or chronic tonsillitis, most patients notice a clear reduction after tonsil surgery. However, if there are also mouth and dental causes, these need to be treated separately.
How can I tell if I have bad breath?
Licking the inside of your wrist and smelling it after a few seconds, or gently scraping the back of your tongue with a clean spoon and smelling it, can give you an idea. Still, the most reliable assessment is the opinion of someone you trust and a medical examination.
Can postnasal drip cause bad breath?
Yes. Thick mucus constantly draining into the throat encourages bacteria to multiply and can cause odor. When the underlying sinusitis or allergy is treated, the odor usually improves as well.
Conclusion
Op. Dr. Tayfun Demirel, an ENT specialist, evaluates patients with bad breath at the practice in Ataşehir, Istanbul, with a detailed examination covering the tonsils, nose, sinuses, the area behind the nose and the larynx. Once the source of the odor is identified, treatment is planned individually, in collaboration with a dentist and other specialists when needed. To book an appointment, please get in touch. This article is for informational purposes only; an in-person examination is required for diagnosis and treatment.
