Breath freshener
Find yourself needing breath freshener? Even though you brush well? Your gut may be to blame. (For Spectrum Health Beat)

Is your breath stinky?

For 8 of 10 people with bad breath, the problem begins in their mouths. Good oral hygiene (and a trip to the dentist) can help solve the issue. For some, sinus infections are the culprit.

But if you have a feeling your halitosis doesn’t start in your head, you could be right, according to gastroenterologist Randall Meisner, MD. In fact, your bad breath could stem from your gut, more formally known as your gastrointestinal system.

According to Dr. Meisner, the No. 1 gastrointestinal-related cause of bad breath is acid reflux, otherwise called heartburn or Gastroesophageal Reflux Disease (GERD).

“Sometimes acid and partially undigested food can make its way up from the stomach to the mouth,” Dr. Meisner said.

Basically, if it tastes bad, it probably smells bad, too.

“If GERD is causing your breath problems, you may also have a sore throat, hoarseness and other ear, nose and throat issues,” Dr Meisner said. Not everyone who has GERD has bad breath, but everyone with unmanaged GERD should see a doctor.

Another cause of awful breath is bacterial overgrowth, which means you have too much bacteria in your small intestine. This can occur in those with diabetes and people who have had intestinal surgery.

“In one severe case, I had a diabetes patient who was tested for bacterial overgrowth after some audible, odorous burps in my office,” Dr. Meisner said.

That’s one way to uncover bacterial overgrowth. The more common (and more pleasant!) method is a simple breath-test machine.

The good news: If you have too much bacteria in your system, antibiotics can solve the issue.

Other stomach problems that could cause bad breath include an intestinal obstruction, cirrhosis of the liver, kidney disease and stomach cancer.

“People with bad breath shouldn’t jump to the conclusion they have stomach cancer,” Dr. Meisner said. “But it’s safe to say that if you’ve seen your dentist and eliminated the common problems of bad breath, consulting a gastroenterologist is a reasonable next step.”