Bad breath (the medical term is halitosis) is an embarrassing but common oral health problem. It's estimated that bad breath impacts more than 50% of the general population around the globe.1 Yet many people who suffer from halitosis are completely unaware of their condition until it’s pointed out by someone else, often leading to awkward social exchanges.

There are a variety of products that promise to eliminate bad breath - from mouthwashes to chewing gum, breath mints, and dissolving tongue strips. In most cases, these only provide a temporary solution. Foul smelling breath can be caused by a number of underlying conditions; and only by treating the root cause can chronic halitosis be stopped for good.

What Causes Bad Breath?

Nearly all (90 percent) of halitosis cases originate in the mouth; the other 10 percent may be caused by gastrointestinal, respiratory, or other non-oral disease. If you experience bad breath only on occasion, it’s probably nothing to be concerned about. Most likely, it has to do with something you ate, an lapse in brushing or flossing, or simply a lack of flowing saliva (which plays a major role in ‘morning breath’). Luckily, good dental hygiene habits are enough to beat the average case of halitosis.

Some of the most common causes of bad breath: 

• Poor oral hygiene: If teeth are not brushed and flossed regularly, particles of food will remain lodged between them. As these particles decay, they release molecular compounds that lead to bad breath. In addition, microbial deposits that build up on the tongue function as bacteria-rich harbors; this is another common source of unpleasant-smelling breath. Regular brushing – including brushing or scraping the tongue - and regular flossing can reduce bad breath.

• Certain foods: Foods like garlic, onions, pickles, radish, and certain spices and condiments contain odor-causing compounds. These compounds are absorbed into the bloodstream and later released when exhaled. Halitosis caused by food is temporary and usually lasts only a few hours.

• Dental problems: Gingivitis, periodontal disease, cavities, dry socket, oral ulceration, and pericoronitis are possible causes. If you notice inflammation of your gums or are experiencing any tooth pain or pain when chewing along with bad breath, visit your dentist to address any possible dental conditions.

• Tobacco and alcohol: Tobacco and alcohol both influence bad breath by introducing volatile compounds into the bloodstream. In addition, tobacco products tend to dry out the mouth, making bad breath even worse since saliva is what keeps your mouth flushed and clear of residual food particles. Insufficient saliva production has a considerable impact on halitosis.

• Dry mouth: Caused by certain medications, health conditions, or excessive alcohol, tobacco, or caffeine consumption, dry mouth is a decrease in natural saliva production. Saliva is very important to oral health. It keeps your mouth clear of debris and provides disease-fighting substances that help ward off cavities and other infections. A lack of saliva means more food particles will decay in the mouth causing bad breath (and other oral health issues), including ‘morning breath’.

Non-oral health conditions

It's possible for bad breath to be caused by an associated health condition. Dieting, snoring, stress, age, and hormonal changes – including menstruation – can also impact your breath. 

The following diseases are known to cause or worsen halitosis:

• Respiratory tract infection
• Tonsillitis
• Sinusitis
• Gastrointestinal disease
• Gastroesophageal reflux disease (GERD)
• Hepatic failure
• Renal (kidney) failure
• Diabetic ketoacidosis
• Leukemia 
• Acute fever

How can I prevent or reduce bad breath?

Most bad breath cases are easy to prevent with healthy dental habits, avoiding odor-causing foods, and regularly visiting your dentist. However, if bad breath persists despite these preventive measures - and underlying health problems have been ruled out - there are a few additional measures you can take :

• Chew sugar-free gum: Look for sugar-free chewing gum marked with the ADA Seal of Acceptance to mask bad breath and stimulate saliva production. Avoid sugary mints or sugar-containing gum, which can increase the risk for tooth decay.

• Try tongue scraping: Don’t just use a toothbrush to clean your tongue. A specially-designed tongue scraper that removes the coating of bacteria accumulated on the tongue can reduce bad breath-inducing sulfur compounds by up to 75 percent. Toothbrush bristles, on the other hand, only reduce these compounds 45 percent according to a comparative clinical trial.

• Keep dentures, retainers, and mouthguards clean: If you wear dentures or have a bridge, clean the device thoroughly at least once a day, and remove it before going to sleep. Do the same for orthodontic retainers and mouth guards, both of which can harbor odor-inducing organisms and bacteria.

• Stay hydrated: The best way to avoid dry mouth and keep saliva flowing is by staying hydrated throughout the day. Drink plenty of water and try to cut back on caffeine and alcohol, both of which can be dehydrating.
  

• Replace your toothbrush: When your toothbrush starts to get frayed or the bristles appear worn, it's time to get a new toothbrush. An old toothbrush won’t do a sufficient job in keeping teeth clean and clear of debris. The American Dental Association recommends replacing your toothbrush every three to four months.

Bad breath happens, but don't stress! Most cases of halitosis can be fixed with simple changes to your lifestyle and oral health routine. UIf the problem persists or is accompanied by other symptoms of dental disease, visit a dentist  as soon as possible to rule out more serious conditions.