Beat The Stank

What Causes Morning Breath, According To A Periodontist

And how to beat bad breath in the long term, because mints and gum are only temporary solutions.

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A man sleeping with his mouth open.
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Bad breath plagues everyone at some point. Well, not babies — thanks to their lack of teeth and because the breastmilk they drink contains odor-fighting white blood cells, their breath always smells like sweet newborn. But for the rest of us, waking up next to our spouse, our toddlers, or our dogs is a reminder that bad breath — and especially morning breath — can be truly revolting.

Thankfully, you can easily take care of bad breath on the spot by popping a mint, and there are steps you can take to keep the stink away from your mouth for the long run. “[Bad breath] affects a lot of people, and it can be easily treated,” says Sawan Malik, D.M.D., a Florida-based periodontist, a type of dentist specializing in gum disease and mouth inflammation. But to fix morning breath and bad breath throughout the day, first you need to know what causes it.

The Causes of Morning Breath

The number one cause of bad breath — in the morning or otherwise — is poor dental hygiene. If you don’t brush your teeth well, you leave a lot of food particles and bacteria to hang out in your mouth for much longer than recommended, which can cause bacteria buildup — and stench.

“Whenever we brush our teeth, we are trying to remove bacteria that accumulates on tooth surfaces,” says Ryan Reichelt, D.M.D., director of clinical practices at Tend, a dental clinic. “This bacteria or ‘plaque’ is that white stuff that can make your teeth feel fuzzy or dirty after a long day of not brushing,” says Reichelt.

The bacteria in dental plaque lives off the foods you eat, especially sugars. Brushing not only clears away the bacteria, but also gets rid of any food left behind that it could chow down on. When you don’t brush, or don’t brush thoroughly, plaque bacteria can thrive. And the bacteria’s waste can release a foul odor and even alter taste, says Reichelt.

Similarly, poor hygiene can lead to your tongue trapping bad smells — because both bacteria and foods’ odor particles get trapped in the tongue. “Bad breath is typically caused by not brushing one's tongue,” says Malik. Using a tongue scraper can also keep the tongue from smelling nasty, he says.

Having a dry mouth can also increase the risk of a stinky smell — and is the main culprit behind morning breath. Dry mouth can give you bad breath because saliva is somewhat like natural mouthwash. If saliva isn’t rinsing your mouth regularly, it can be hard to wash away any lingering food particles or odorous bacteria.

What Causes Bad Breath Throughout The Day?

Even if you’re brushing well, pungent foods can cause bad breath in the short term, although how they do so depends on the particular food. Coffee and alcohol cause dry mouth, which can in turn cause bad breath. But garlic and onions, for example, release sulfur compounds in the mouth that can stick around for hours, and they contain smelly chemicals that are absorbed into the bloodstream, flow to the lungs, and are released when you breathe. Mixing strong-smelling foods with saliva and bacteria in the mouth only accentuates their reek.

And food that gets stuck in teeth can allow bacteria to grow until the next time you brush. Meat and other foods high in protein are particularly likely to give you bad breath because plaque bacteria thrive off them.

Smoking can cause bad breath too. The smell is generated when stale smoke particles linger in the mouth and throat, mixing with saliva and bacteria in the mouth and causing “smoker’s breath.”

If you have good dental hygiene your bad breath is persistent, a mouth infection could be the cause. The infection can be anything from a small cut that’s gotten infected, a carious tooth, a fungal infection of the tongue, or the development of gum disease, says Andres Pinto, D.M.D., a professor at the Case Western Reserve University School of Dental Medicine. Gum disease, or periodontal disease, occurs with degradation of the structures that support teeth, such as gums and bone, caused by tartar seeping under the gum lining and infecting the area. “Almost half of the U.S. population suffers from some degree of periodontal disease,” says Pinto.

Last but not least, other health conditions such as stomach reflux, sinus infections, postnasal drip, and metabolic issues can result in bad breath because of the bacteria involved with them. The bacteria lingers in the body, and makes its way to the mouth, especially if you’re experiencing a bacteria imbalance in the gut. In the case of stomach reflux, for example, acids and bacteria travel from the stomach to the mouth via the digestive tract, where waste of the latter can cause bad breath.

Kids get bad breath for largely the same reasons that adults do, but you should also look out for mouth breathing, which can cause bad breath via dry mouth, and for foreign objects stuck in the nose, which can cause an icky-smelling infection.

How To Get Rid Of Morning Breath

Bad breath remedies are relatively straightforward. On the spot, try a mint, mouth freshener spray, or sugarless gum to combat the odor. Specifically, consider products with xylitol, a chemical compound that helps prevent the formation of plaque.

The main advice for combating bad breath, however, is to maintain good dental hygiene. “The first place to start is your general dentist, and they can guide you on proper care,” says Malik. Implement good brushing and flossing techniques twice a day (without overdoing it, because that can cause damage too).

“A great tip to remember is the acronym ‘FBI,’ meaning to floss first, brush, and then irrigate with a mouth rinse or a water pick,” says Malik. When flossing, take your time rather than snapping the floss up and down quickly, Malik says. When choosing a toothbrush, opt for electric for greater effectiveness, and don’t forget to brush your tongue, he adds.

On top of that, try eating more hard fruits and vegetables such as apples and celery, which can act as a natural mouth rinse. That’s because they’re full of fiber, and they brush food residue away from your teeth. They also incentivize the production of saliva, which rinses your mouth out. Be sure to stay hydrated by drinking plenty of water because that will increase saliva production too. And, a new review study finds, taking probiotics could help with bad breath too.

If you’re worried your bad breath might be a sign of something serious, especially if you’re experiencing pain or bleeding in your mouth, see a dentist. “We have hardware capable of measuring volatile organic compounds, common culprits of bad breath,” says Pinto, meaning that dentists can examine the smell in your mouth to pin-point exactly what’s happening in there.

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