Bad breath, or halitosis, is common and can have several causes. In many people the source is in the mouth, but persistent odor can also be associated with dry mouth, nasal or throat conditions, medications, tobacco use, or certain medical conditions. [1][2]
Medically reviewed by Dr. Walter Kostrzewski, DMD
Dr. Kostrzewski has more than two decades of experience in dentistry and reviews the dental information published by ACE Dental Resource.
What Causes Bad Breath?
| Possible cause | Clues or explanation |
|---|---|
| Tongue coating and oral bacteria | Bacteria can break down debris and produce odor-causing compounds. |
| Gum disease | Persistent odor or bad taste can occur with periodontal disease. |
| Dry mouth | Reduced saliva means less natural cleansing; medications and mouth breathing can contribute. |
| Food and tobacco | Some foods and tobacco can temporarily or persistently affect breath. |
| Dental problems | Decay, infections, and other oral conditions may produce odor. |
| Nasal or throat conditions | Sinus disease, post-nasal drainage, and some throat conditions can contribute. |
The ADA notes that volatile sulfur compounds are major contributors to oral malodor and can arise from food breakdown, dental plaque, and bacteria associated with oral disease. [2]
Could Bad Breath Mean Gum Disease?
It can. Persistent bad breath is one possible sign of gum disease, especially when accompanied by bleeding, swollen gums, recession, or loose teeth. It is not specific to gum disease, however. If you also have gum symptoms, see our Gum Disease guide.
What Can You Do About Bad Breath?
- Brush twice daily with fluoride toothpaste.
- Clean between your teeth regularly.
- Gently clean your tongue as part of your normal oral-hygiene routine.
- Stay adequately hydrated, particularly if dry mouth is contributing.
- Avoid tobacco.
- Clean dentures and dental appliances according to your dentist’s instructions.
- Arrange a dental examination if the odor persists despite good home care.
These steps address common oral contributors, but they do not guarantee that every case of halitosis will resolve. The cause needs to be identified when the problem persists. [1][2][3]
Does Mouthwash Cure Bad Breath?
Some mouthrinses can reduce odor temporarily, while therapeutic rinses containing active ingredients may provide longer-lasting control in selected situations. Mouthwash should not be treated as a substitute for brushing, interdental cleaning, or treatment of an underlying dental problem. [2]
Bad Breath and Dry Mouth
Saliva helps clear food debris and bacteria. Dry mouth can therefore contribute to bad breath. If a medication seems to be causing persistent dryness, do not stop it on your own; discuss the problem with the prescribing clinician or dentist.
When Should You See a Dentist?
See a dentist if bad breath persists despite good oral hygiene, especially if you also have bleeding gums, swelling, tooth pain, loose teeth, a persistent bad taste, or another new oral symptom. A dental examination can look for gum disease, decay, infection, and other oral causes.
What If the Dentist Finds No Oral Cause?
If a dental examination does not identify an oral source and the problem persists, your dentist may recommend evaluation for other possible causes. Depending on your symptoms, this may involve a physician or another healthcare professional.