If you're not following the 8x8 rule (aka drinking eight 8-ounce glasses of water a day), you might be dehydrated — and this might be the cause of your bad breath. "The saliva in our mouth contains antibodies that can kill some of the bad breath causing bacteria," explains Dr. Baise. "When we are dehydrated our mouths still contain enough moisture to support bacterial growth, but not enough saliva to contain the antibodies necessary to halt this growth." Therefore dehydration can cause bad breath. Plus, there are plenty of other health reasons to stay hydrated, so drink up!

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Many people know that smoking can cause bad breath, but the new trend of vaping can too. This is for two reasons, according to Dr. Baise: "The hot vapor that enters your mouth can dry your mouth, therefore reducing the amount of antibody-rich saliva in your mouth and the nicotine in your vape causes vasoconstriction in your gums," he says. "This makes the protein in you gums more susceptible to break down, which is the main cause of bad breath."

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While you'd think drinking something sweet would only enhance your breath, it surprisingly does that exact opposite. "This is because the bacteria which causes bad breath requires sugar to survive and multiply," explains Dr. Baise. "As sugary, sticky drinks coat the mouth for longer than foods, these are particularly conducive to having bad breath." Since this includes fruit juice and smoothies, it's best to brush your teeth after sipping to kill some of the odor-causing bacteria.

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Gastrointestinal or digestive issues, including acid reflux, can lead to bad breath, according to Dr. Marashi. "The stomach acids have odor and also dry out the throat and mouth, further exacerbating the problem," he says. "At nighttime, laying flat can allow the stomach acids to move up into the mouth." Sleeping at an angle, propped up on pillows, can help reduce the symptoms of reflux as gravity helps keep the acids down in the GI tract. If you suffer from digestive issues, Dr. Marashi suggests consulting with your doctor about how best to alleviate the symptoms of bad breath that come along with them.

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Bad breath can be caused by caused by a myriad of diseases, including lung infections such as bronchitis, emphysema and pneumonia. "Lung cancer usually causes bad breath and is now being used in early detection," says Dr. Stimeman. "Liver failure is another condition that's often signaled by a sweet smelling, musty odor on the breath as the body tries to get rid of by-products of sulfur-containing amino acid breakdown." This symptom is also being used for early detection of diabetes. That said, if you think something's up, it's always best to check in with your physician.

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