The truth about bad breath

Is last night's garlic-laden pasta or your poor brushing technique causing your halitosis—or is it something else altogether?

Published: July 2015

Rarely does a patient come to see me for a problem with bad breath. But recently, a 64-year-old accountant came into my office for an appointment, continually holding a cupped hand over his mouth as he answered questions about his medical history. He was firmly convinced that his breath was offensive.

When I commented that his cover-up made him hard to understand, his wife noted that he had been doing it for many years without good reason and much to her annoyance. And from what my own nose told me after examining him, his fears were unwarranted.

Do you or don't you?

The fact is, we’re not really very good at detecting halitosis, or bad odors in our own breath. As many as one in four people who complains of bad breath doesn’t actually have it. Although the exact prevalence of the condition is unknown, it is thought to range from 15 to 30 percent based on studies done in several countries, and men have the dubious distinction of outscoring women.

But whether you do or don’t—and there’s no definitive way to tell, short of asking the opinion of others—might be moot. That’s because the accompanying anxiety and fear can cause suffering as well as affect relationships, as depicted in myriad ads for mints and mouth rinses. If you have received confirmation of your halitosis from a friend or family member, read on.

Avoid the offenders

When it comes to short-term bad breath, garlic and possibly scallions and raw onions are common offenders. Those fragrant foods can cause breath problems even if you cleanse your mouth meticulously after eating them. Garlic’s odor can be excreted by the lungs for up to two days after ingestion. Alcohol, coffee, and smoking also cause their own characteristic breath odor.

In an overwhelming majority of chronic halitosis cases, the problem originates in the mouth. The human oral cavity is a storehouse for harmless bacteria, which feed on the leftover bits of food that get trapped between the teeth and deposited in crevices along the gum line.

As a result, smelly amino acids are released in gaseous form. It is probable that dozens of those gases, including hydrogen sulfide (think rotten eggs) and an aptly named amino acid called cadaverine, combine to produce malodorous breath.

In addition, those bacteria can initiate and perpetuate infections including gingivitis and periodontal disease along the gum line, leading to rank odor.

The back part of the tongue can contribute to bad breath by providing a surface where bacteria can feed on remnants of postnasal drip. The tonsils can also cause an unpleasant smell.

Chronic halitosis is rarely the result of disorders of the esophagus, intestine, or stomach. But the occasional burp or reflux of stomach acid can produce temporary foul-smelling breath.

Find out if low-fat diets work and whether these trendy foods are actually healthy.

The sweet smell of success

These strategies can help you keep your breath smelling fresh:

  • After eating, rinse your mouth with water to help you dislodge any food particles that might remain there. You might consider a mechanical irrigating device to help with rinsing.
  • Rinse and gargle twice each day with plain water or warm water in which half a teaspoon of salt has been dissolved. It’s best not to gargle twice per day with rinses that contain alcohol, which might be carcinogenic to tissue in the mouth.
  • Use a soft, plastic tongue scraper before going to bed to gently remove deposits of bacterial debris from the back of the tongue.
  • Eat a high-fiber diet to help with mouth cleansing. Note that pineapple might contain a beneficial enzyme.
  • See your dentist to treat any dental or gum infections. Go to your hygienist for regular professional cleanings. How often you go will depend on your overall dental health.
  • Use a mint or a scented spray now and then if you think it’s needed for bad breath.

Editor's Note:

This article also appeared in the August 2015 issue of Consumer Reports on Health.

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