Halitosis: 10 reasons -- and remedies -- for your bad breath

Up to 80 million people have chronic bad breath.

(CNN)Are you constantly failing the "sniff test," in which you surreptitiously blow into your cupped hands to check for stinky breath?

(Tip: If you can smell it, then your breath is flat-out noxious, as most of us can't tell on our own, dentists say.)
If your mouth funk rates as "stank-nasty," then you -- and all those around you -- are victims of halitosis, breath that smells so repulsive it could only be attractive to buzzards and flies.
    You're not alone. Up to 80 million people have chronic bad breath, according to the Academy of General Dentistry.
      Besides the obvious impact on your popularity, bad breath can be a sign of diseases and conditions, some serious.
      While you race for a mint, it might help to know the top 10 reasons why your breath smells bad in the first place and what you can do about it.

      1. You stink at brushing.

        Yes, poor dental care is a leading cause of bad breath. When food is trapped between your teeth and under your gums, bacteria get busy breaking it down, leaving behind putrid gases that smell like rotten eggs or worse (even as bad as poop).
        One way to tell if you have bad breath, dentists say, is to floss and then smell the thread. If there's a rank smell on the floss, you'll know for sure your breath is toxic.
        The good news is that you can easily fix this type of bad breath by brushing your teeth with fluoride toothpaste twice a day and flossing regularly. While the brush is in there, don't forget your tongue and cheeks; studies show that brushing them can reduce bacteria load.
        Cosmetic mouthwashes and gum only temporarily cover up the stink, dentists warn, because neither reduces bacteria.

        2. You ate or drank something smelly.

        Coffee. Garlic. Fish. Eggs. Onions. Spicy food. The foods we eat can easily cause bad breath.
        Many of the foods that contribute to stinky breath do so by releasing sulfides. Sulfur, as you know, smells like rotten eggs.
        A mint or stick of gum might mask the reek, but be warned: Odors from some of what you eat can stick around until the food works its way through your system -- even if you brush. According to the Academy of General Dentistry, the allyl methyl sulfide in coffee, onions and garlic can stay in your bloodstream and be expelled via your breath up to 72 hours after consumption.
        Try fighting back with other foods, such as lemons, parsley and crisp fruits and veggies such as apples or carrots that stimulate saliva production, which your mouth relies on to wash away impurities. Drinking water helps too! Caffeine, on the other hand, slows the production of saliva.

        3. You eat a lot of sweets.

        Before you plop that next sugary candy, cake or cookie in your pie hole, listen closely. You might hear the chorus of cheers coming from the bacteria that live in your mouth. For them, sugar is a superfood, and boy, do they have a party gobbling it down, leaving a stink behind.
        Dentists say sticky candies such as gummies and caramels are the worst offenders; if you must eat something sweet, they suggest (oh, joy!) plain chocolate. It has less sugar than many other candies and dissolves more quickly in the mouth.

        4. You're on a low-carb diet.

        Eating a lot of protein and few carbs forces your body into ketosis, when your system begins to burn fat cells for energy.
        The process creates waste products called ketones. Too many of those aren't good, so your body has no choice but to make you a walking stank house, excreting ketones via your urine and your breath. It's a rank odor, which many compare to rotten fruit.
        Try drinking extra water to flush ketones out of your body. If you use breath mints, candies or gum, be sure they are sugar-free.

        5. You're a mouth breather.

        At night, saliva production is decreased, which is why many of us wake up with a rotten taste (and smell) in our mouths, even after diligent brushing and flossing.
        Mouth breathing or snoring, such as from sleep apnea, further dries out the mouth, making your breath even more foul. Called xerostomia, dry mouth is not only unpleasant but potentially harmful. You might develop a sore throat, hoarseness, difficulty speaki