8 Things Your Breath Reveals About Your Health

Stop throwing mints at the problem—find out what's causing your bad breath. 

man checking his breath in the bathroom mirror
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By Rose Hayes

Your breath can tell a lot about your health, from clues about your daily habits, to evidence of undiagnosed medical conditions and more. In fact, practitioners of traditional Chinese medicine have used the smell of people’s breath to help make diagnoses for centuries. Dogs can even be trained to detect cancer based on the way someone's breath smells. Here are eight things your mouth odor can reveal, plus ways to get help for common breath issues.

woman flossing teeth in bathroom mirror
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Your hygiene needs help

Most often, bad breath comes from debris that builds up in your mouth. You may feel—and smell—much cleaner after just a few easy hygiene tweaks:

  • Sweep the gunk from your tongue with a tongue cleaner
  • Stick out your tongue while gargling to get mouthwash farther back in your throat

And keep flossing. Headlines in 2016 pointed to a lack of research behind this simple habit, but the American Dental Association stands by its recommendation to floss daily. There may not be enough studies to show a clear link between flossing and cavity prevention, but it does get sticky, smelly plaque out from between your teeth. Plus, early studies suggest flossers have less gingivitis, or gum inflammation.

woman's hands holding a fast food hamburger in her car
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You frequently hit the drive-thru

Need another reason to avoid fast foods and processed meals like instant noodles? One team of researchers discovered higher rates of halitosis, or bad breath, among young people who regularly ate these foods.

This isn’t entirely surprising since diets high in certain foods like sugar, garlic and onions have long been associated with stinky breath. Garlic odor is especially notorious because it sticks around even after brushing. How? It circulates through your system after digestion and is exhaled through your lungs. So steer clear of clingy garlic the night before your next big interview!

man in an exam chair at the dentist.
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You skip the dentist

Bad breath can signal conditions like gingivitis and tooth decay, which require professional attention. Avoid tooth decay by seeing your dentist every six months for a checkup and cleaning.

Dental devices can affect your breath when food particles get lodged underneath them, too. If you wear dentures, remove and clean them nightly. Then, brush your mouth and gums thoroughly to remove germs and promote circulation. Also, dentures should fit snugly enough to eat crisp produce with ease—if they don’t, see your dentist to keep friction-related sores from developing. 

woman reaching for sugar-free candies at her desk
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You have dry mouth

Breath tends to smell worse when your mouth is dry since saliva normally cleans away food particles. Dry mouth can come from certain medications, illnesses or mouth breathing. Sound familiar? These tricks may help:

  • Suck on sugar-free candies, but choose ones with malic acid, which stimulates saliva production.
  • Sip sugar-free drinks or water to keep your mouth moist (swishing and spitting works too).
  • Avoid drying, acidic substances like coffee and alcohol.

If you're still feeling dry after that, consider saliva replacement products like Biotene, which you can find at the pharmacy or grocery store. 

senior man with allergies blowing his nose into a tissue
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Your allergies are acting up

Allergies can cause postnasal drip, or the dripping of mucus from your nose, down into the back of your throat. Mucus then causes bad breath when it lands on your tongue and mixes with mouth bacteria.

It’s important to treat the cause of your postnasal drip. If it’s allergies, ask your doctor if medications like antihistamines, decongestants or prescription nasal sprays could help get your symptoms under control.

It’s also important to drink plenty of water since fluids loosen mucus and can keep it from lodging in your throat. Nasal irrigation kits and saline sprays can moisten and clear your nasal passages, as well. 

senior woman sitting on her couch holding her chest due to heartburn pain
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You have heartburn

If you get occassional heartburn, it's common to feel self-conscious about your breath after burping. It’s rare for bad breath to actually come from your gut, though, since the flap, or spchincter at the top of your esophagus is usually closed. However, chronic heartburn may result in bad breath.

Another possible culprit? The stomach bacteria H. pylori. This germ makes sulfur compounds that can create unpleasant smells, although more evidence is needed to determine exactly how much of an effect this has on halitosis.

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You’re a smoker

All forms of tobacco cause foul breath. They dry out your mouth, irritate your gums and leave an odor that’s difficult to shake. In fact, the smell can remain on your breath for over a day after your last cigarette. It can even be detected on the breath of people exposed to second-hand smoke.

In addition to bad breath, tobacco yellows your teeth and raises your risk of mouth cancer and gum disease. If you’re trying to quit tobacco, Sharecare offers personalized advice through its AskMD Consultation feature. Make an action plan or reach out to a Sharecare expert who specializes in addiction medicine. 

female doctor discussing exam results with a female patient
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You might have a more serious medical condition

Sometimes, the smell of your breath can signal a more serious illness. There are many conditions that lead to changes in breath odor, including certain cancers like stomach and lung cancer, as well as kidney and liver failure.

One example is the acetone-like smell, similar to nail polish remover, on the breath of people with diabetic ketoacidosis (DKA). This complication of diabetes can happen during periods of stress, illness and severe hunger. If you’re living with diabetes, it’s important to know the risk factors and symptoms of DKA since it can be life threatening.

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