Is there a connection between bad breath and acid reflux? Gastroesophageal reflux disease (GERD) is a condition where stomach contents return up the esophagus, sometimes all the way to the mouth, causing heartburn and an unpleasant bitter taste. Many professionals and health writers list GERD as a possible cause of bad breath, but few go into any detail about what produces the bad odor. Given that there may be a demonstrable connection, there are a couple of explanations we can consider.
First, symptoms of bad breath and acid reflux often strike after consumption of a large meal. Many foods, though we love to eat them, do not smell too good on the breath afterwards. These include garlic (probably the best known food cause of bad breath), onions, strong cheeses, spicy foods, alcoholic beverages, and a number of other foods. When a recently consumed meal is pushed back up the esophagus, it would not be surprising that an unpleasant smell is produced on the breath.
Secondly, it's no secret that one's stomach contents do not smell too good. The stomach is an acid environment where foods start to break down in preparation for digestive processes in the intestine. If enough time has passed since the food was consumed, stomach contents that return up the esophagus in a case of GERD will have the sharp acidic smell of vomit – an unpleasant odor producing an atypical halitosis and suggesting a link between bad breath and acid reflux.
Thirdly, in cases of chronic GERD, acid stomach liquids repeatedly come in contact with, and burn, the lining of the esophagus. Because the damage recurs frequently, the tissue never has time to heal completely and is thus chronically irritated with continual production of dead tissue. Dead tissue has an unpleasant odor, and when it is present in the esophagus, it's likely to produce an indirect connection between bad breath and acid reflux.
But, the truth is, there does not seem to be a really strong correlation between bad breath and acid reflux itself. A relatively low percentage of people with GERD experience chronic halitosis. Instead, researchers recently reported at the 71st Annual Scientific Meeting of the American College of Gastroenterology (2006) that there is an apparent connection between proton pump inhibitors (drugs commonly used to treat GERD), and chronic bad breath. The drugs, it seems, may cause an overgrowth of odor producing bacteria in the mouth – and anaerobic odor producing bacteria in the mouth are by far the most common cause of chronic halitosis.