You’ve heard it a million times before: The key to good oral health is regular brushing. But even if you brush, gurgle mouthwash and scrape your tongue, plaque and bacteria can still linger in and around your teeth.
That’s why dentists strongly recommend flossing, too, ideally once a day. Keeping up with these flossing recommendations can feel like a chore (and, yes, your dentist can tell if you actually floss) but there’s one telltale sign you need to up your flossing game: Your floss stinks when you smell it.
“If the floss smells bad, it might indicate plaque buildup with bacteria accumulation, food impaction or gum inflammation,” Dr. Natalie Jeong, the chair of the department of periodontology at Tufts University School of Dental Medicine, told HuffPost.
Here’s what stinky floss means — and what you should do about it:
What does flossing actually do?
Before we dig into what smelly floss can tell you about your oral health, here’s a quick review of what flossing accomplishes in the first place.
According to Jeong, brushing your teeth two times a day — while effective at preventing oral diseases — doesn’t fully clean the spaces between your teeth. “Brushing cleans the surfaces of your teeth. However, your toothbrush bristles can’t effectively reach between teeth,” she explained. Over time, food particles and plaque can harden and develop into tartar, which leads to gum disease.
This is where flossing comes in. It cleans the narrow spaces that your toothbrush can’t reach, between your teeth and under your gum line. “Brushing without flossing is like washing only the front and back of a dish but not the sides,” Jeong said.
According to Marisol Tellez Merchan, the chair of the department of oral health sciences at Temple University’s Maurice H. Kornberg School of Dentistry, flossing has been shown to reduce gingival inflammation, tooth loss and tooth decay.
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If your floss stinks, it’s a warning sign your mouth is harboring bacteria.
What smelly floss means
If you floss and you take a whiff of the string afterward and it has a stench, you may have some bacteria or food lingering in your mouth.
A mild odor isn’t usually a concern, especially if you recently ate or haven’t flossed in a while, according to Jeong. To her, it’s a sign you may not be brushing or flossing efficiently.
“Smelly floss, or evidence of any food debris stuck in the floss or surrounding tooth structure, is a sign you may need to floss a bit more or even brush again,” Merchan said.
But does this mean you should smell your floss every time you do it? Not necessarily, Jeong said. But giving it a quick sniff every once in a while may provide some helpful insights into your oral health.
If you brush and floss regularly and your floss still has a strong or foul scent, set up an appointment with a dentist or periodontist. They can conduct an exam to determine if an underlying health issue is causing the odor.
Your stinky floss may just be harboring trapped bacteria or food, but it could be indicative of a more serious issue such as gum disease, like gingivitis or periodontitis, or decay under a crown or filling, Jeong said.
Here’s the most effective way to floss
The most ideal approach is to floss at least once a day. According to Jeong, nighttime is best.
Her advice: Wrap about 18 inches of floss around your middle fingers, leaving an inch or two to slide between your teeth and down under your gum line. Make sure to use a clean section of floss for each tooth.
If that feels unrealistic, aim to floss every few days. “Even three times a week is better than flossing never,” she said.
