The microscopic uneven surface of the tongue can trap bacteria that produce odors, contributing to bad breath.
Bad breath, also called halitosis, can be embarrassing and in some cases may even cause anxiety. It's no wonder that store shelves are overflowing with gum, mints, mouthwashes and other products designed to fight bad breath. But many of these products are only temporary measures because they don't address the cause of the problem.
Certain foods, health conditions and habits are among the causes of bad breath. In many cases, you can improve bad breath with consistent proper dental hygiene. If simple self-care techniques don't solve the problem, see your dentist or physician to be sure a more serious condition isn't causing your bad breath.
Bad breath odors vary, depending on the source or the underlying cause. Some people worry too much about their breath even though they have little or no mouth odor, while others have bad breath and don't know it. Because it's difficult to assess how your own breath smells, ask a close friend or relative to confirm your bad-breath questions.
When to see a doctor
If you have bad breath, review your oral hygiene habits. Try making lifestyle changes, such as brushing your teeth and tongue after eating, using dental floss, and drinking plenty of water.
If your bad breath persists after making such changes, see your dentist. If your dentist suspects a more serious condition is causing your bad breath, he or she may refer you to a physician to find the cause of the odor.
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Most bad breath starts in your mouth, and there are many possible causes. They include:
- Food. The breakdown of food particles in and around your teeth can increase bacteria and cause a foul odor. Eating certain foods, such as onions, garlic and spices, also can cause bad breath. After you digest these foods, they enter your bloodstream, are carried to your lungs and affect your breath.
- Tobacco products. Smoking causes its own unpleasant mouth odor. Smokers and oral tobacco users are also more likely to have gum disease, another source of bad breath.
- Poor dental hygiene. If you don't brush and floss daily, food particles remain in your mouth, causing bad breath. A colorless, sticky film of bacteria (plaque) forms on your teeth. If not brushed away, plaque can irritate your gums and eventually form plaque-filled pockets between your teeth and gums (periodontitis). Your tongue also can trap bacteria that produce odors. Dentures that aren't cleaned regularly or don't fit properly can harbor odor-causing bacteria and food particles.
- Dry mouth. Saliva helps cleanse your mouth, removing particles that cause bad odors. A condition called dry mouth or xerostomia (zeer–o-STOE-me-uh) can contribute to bad breath because production of saliva is decreased. Dry mouth naturally occurs during sleep, leading to "morning breath," and it worsens if you sleep with your mouth open. Chronic dry mouth can be caused by a problem with your salivary glands and some diseases.
- Medications. Some medications can indirectly produce bad breath by contributing to dry mouth. Others can be broken down in the body to release chemicals that can be carried on your breath.
- Infections in your mouth. Bad breath can be caused by surgical wounds after oral surgery, such as tooth removal, or as a result of tooth decay, gum disease or mouth sores.
- Other mouth, nose and throat conditions. Bad breath can occasionally stem from small stones that form in the tonsils and are covered with bacteria that produce odor. Infections or chronic inflammation in the nose, sinuses or throat, which can contribute to postnasal drip, also can cause bad breath.
- Other causes. Diseases, such as some cancers, and conditions such as metabolic disorders, can cause a distinctive breath odor as a result of chemicals they produce. Chronic reflux of stomach acids (gastroesophageal reflux disease, or GERD) can be associated with bad breath. Bad breath in young children can be caused by a foreign body, such as a piece of food, lodged in a nostril.
March 10, 2018
- Bad breath: Causes and tips for controlling it. The Journal of the American Dental Association. 2012;143:1053.
- Mark AM. Targeting bad breath. The Journal of the American Dental Association. 2015;146:932.
- What is halitosis? Academy of General Dentistry. http://www.knowyourteeth.com/infobites/abc/article/?abc=H&iid=306&aid=1254. Accessed Jan. 14, 2016.
- Dry mouth. National Institute of Dental and Craniofacial Research. http://www.nidcr.nih.gov/oralhealth/topics/drymouth/drymouth.htm. Accessed Jan. 14, 2016.
- Should I floss? Academy of General Dentistry. http://www.knowyourteeth.com/infobites/abc/article/?abc=f&iid=302&aid=1244. Accessed Jan. 14, 2016.
- Diagnosing and treating bad breath. Dental Abstracts. 2014;59:203.
- Tongue scrapers only slightly reduce bad breath. Academy of General Dentistry. http://www.knowyourteeth.com/infobites/abc/article/?abc=t&iid=306&aid=3192. Accessed Jan. 14, 2016.
- Bollen CML, et al. Halitosis: The multidisciplinary approach. International Journal of Oral Science. 2012;4:55.
- Salinas TJ (expert opinion). Mayo Clinic, Rochester, Minn. Feb. 13, 2016.