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How Often Do You Really Need to Floss?

Unfortunately, the answer isn't "never."
Woman flossing
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It’s the perennial oral-health question: How often should you floss? Some people do it three times a day. Some do it whenever they remember. And others only do it a few times after a dentist visit, then the floss goes back to the recesses of their medicine cabinet.

As insignificant as the act may seem, flossing is actually at the center of an oral-hygiene debate.

Forgetful flossers were vindicated when the government removed its recommendation for daily flossing from the 2015-2020 version of the Dietary Guidelines for Americans, a set of recommendations the departments of Agriculture and Health and Human Services release every five years. The year before the report’s release, the Associated Press asked the two departments for their evidence that flossing was actually beneficial. “In a letter to the AP, the government acknowledged the effectiveness of flossing had never been researched, as required,” the AP said in an August 2, 2016 article.

There was barely time to put down the floss before the American Academy of Periodontology quickly responded the same day to say that actually, flossing is an important part of daily oral hygiene. They acknowledged that studies showing as much are generally lacking, but “in the absence of quality research, patients should continue to include flossing as a part of their daily oral hygiene habit.” Two days later, the American Dental Association released a statement saying that interdental cleaners such as floss are “an essential part of taking care of your teeth and gums.”

Confused about how important flossing actually is and how often you should be doing it? Here’s what you need to know.

What even is the point of working that little piece of string between your teeth?

Flossing, proponents say, helps to remove food particles and bacteria from between your teeth and along your gumline. When this bacteria builds up, it forms plaque, a sticky, colorless film that can threaten your oral health by contributing to tooth decay and gingivitis. Gingivitis is the first stage of gum disease, which can then evolve into periodontitis, the full-blown form of this health condition. “Gingivitis is the inflammation of the gums around your teeth, which will progress to periodontitis, which is inflammation of the gums in combination with bone loss,” dentist Greg Gelfand, D.D.S., tells SELF. When left untreated, periodontitis can lead to tooth loss.

Dr. Gelfand says he can quickly tell when a patient hasn’t touched floss in too long, telling SELF that he more often sees “bleeding gums, a high rate of cavities, bone loss, and bad breath” in people who don’t make flossing a habit.

You're not alone if you're confused about how important floss is or how often you should be doing it.

The differing recommendations stem from the absence of solid, large-scale randomized clinical trials to support flossing as an essential part of taking care of your teeth and gums, periodontist David Genet, D.M.D., tells SELF. What research there is doesn’t paint a very convincing picture.

For example, a 2011 review of 12 studies with a total of 1,083 people only found “some” evidence that flossing in addition to tooth brushing reduces gum disease compared to tooth brushing alone. Based on 10 of the 12 studies in the review, published in the Cochrane Database of Systemic Reviews, there was also only “weak, very unreliable” evidence that flossing plus tooth brushing may be associated with a small reduction in plaque at one and three months.

A 2015 meta-review published in the Journal of Clinical Periodontology came to a similar conclusion. The authors analyzed six reviews (including the above one from 2011) with a combined 3,534 people to see how effective various methods, like flossing, are at cleaning between the teeth. “The majority of available studies fail to demonstrate that flossing is generally effective in plaque removal,” the study authors concluded. “Routine instruction [from dentists and periodontists] in using floss is not supported by scientific evidence.”

According to oral-health experts, though, you’re not just off the hook for flossing, no matter what the science says (or doesn’t). “If you floss after you brush and there are food particles on your floss that otherwise would’ve remained between your teeth, it is hard to believe that the process of flossing is not beneficial,” says Dr. Genet. “Maybe flossing is not as ‘essential’ as was previously suggested, but it definitely plays an important role in maintaining your dental and periodontal health.”

Fine, fine, flossing sounds pretty important. So how often should you actually do it?

In an ideal world, you’d floss every time you brush your teeth, which would be at least twice a day—morning and night—and maybe a third if you brush after lunch, too, Lindsay Marshall, D.M.D., a dentist in Ardmore, Pennsylvania, tells SELF.

Dr. Gelfand agrees, noting that “we should brush and floss after every meal to make sure there is no food or bacteria accumulating between the teeth.” Unfortunately, for some people, flossing feels like a Sisyphean task, and doing it three times a day is just laughable. In that case, Dr. Gelfand recommends doing it at least once a day. So do the American Dental Association and American Academy of Periodontology.

Flossing is only effective, however, if you do it correctly. Many people don’t.

Imagine wasting every second you spend flossing like a responsible human being because you’re not doing it properly. Don’t do that to yourself. “Many people just slide the floss into the space between the two teeth and just go up and down, which does not clean both teeth equally,” Dr. Gelfand says.

Here are Dr. Gelfand’s tips for flossing more effectively:

  • When using traditional floss instead of another type of interdental cleaner, use a long piece around 18 inches so there’s enough clean floss to get in between all your teeth.
  • Tie the floss around your middle finger on both hands and pinch it with your thumbs.
  • Keep the distance between your two hands small and go between each tooth in your mouth. Do this gently to avoid harming your gums.
  • To clean both teeth, make a C shape, hugging one tooth and sliding up and down, then make a C shape around the adjacent tooth and repeat the motion. Don’t forget the back sides of your last teeth!
  • Consider using a mouthwash after flossing to rinse your mouth and remove as much bad bacteria as possible. Here’s information from the American Dental Association on choosing the best one for you.

The bottom line: When combined with brushing your teeth, flossing every day is a great way to keep your mouth healthy and make your dentist proud, which is a strangely satisfying feeling.

But if you have a health issue that compromises your dexterity, like rheumatoid arthritis, there are other options out there. “Various products on the market can achieve the same level of clean as flossing,” Dr. Gelfand says. “Water flossers, dental picks, floss holders, and soft picks are great alternatives to flossing.” If you’re not sure which is the best for you, try experimenting with different types of interdental cleaners or asking your dentist if they have any recommendations.

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