To Floss or Not to Floss?

Medically Reviewed by Alfred D. Wyatt Jr., DMD on November 22, 2016
3 min read

Your dentist has probably been telling you to floss for years. If you’ve resisted that advice, you’ve got a lot of company: 36% of Americans would rather do something unpleasant, like clean the toilet, than wedge waxed string between their teeth.

That’s why many cheered at a news report that flossing might not be necessary. The Associated Press reviewed 25 studies and concluded that flossing didn’t have proven health benefits.

Adding to the anti-flossing evidence, the U.S. Department of Health and Human Services (HHS) and Department of Agriculture (USDA) have removed it from their guidelines for good oral health.

Not so fast. Many dental experts aren’t on board.

“While the research on [the connection between] flossing and cavities is hazy, the research on flossing’s role in preventing gum disease is much clearer,” says Leena Palomo DDS, an associate professor of periodontics at Case Western Reserve University in Cleveland, Ohio. “That’s why dentists, hygienists, and periodontists continue to recommend flossing.”

One review of 12 studies found that people who brushed and flossed regularly were less likely to have bleeding gums. They had lower levels of gum inflammation (called gingivitis, the earliest stage of gum disease), too.

“Food that’s left between teeth causes gum inflammation andtooth decay. Flossing is the only way to remove it. A toothbrush just can’t get between teeth,” says dentistry professor Sivan Finkel, DMD, of New York University College of Dentistry.

About half of all Americans have gum disease, also known as periodontal disease. That’s a chronic inflammatory disease that shows up when bacteria in plaque (a sticky film that forms on your teeth) below the gum line cause swelling and irritation. Left untreated, it can lead to receding gums and tooth loss.

Gum disease is also linked to heart disease, rheumatoid arthritis, diabetes, premature birth, and many other health conditions. “Your mouth is a mirror for the rest of your body,” Palomo says.

The connection between gum disease and health isn’t entirely clear. Some scientists think more bacteria left in your mouth end up in your bloodstream, where they may contribute to inflammation in other areas, like your heart. What experts do know is that people who don’t have gum disease are less likely to have health problems like heart disease.

“Flossing removes debris that contains bacteria that cause gum disease,” Palomo says.

The American Academy of Periodontology and the American Dental Association recommend flossing. “It makes sense to get dental advice from these dental organizations,” Palomo says.

In fact, many dentists and periodontists say the reason they recommend flossing isn’t because of research. Instead, it’s because of what they see in their patients.

“In my practice, it’s clear that people who floss daily have healthier gums and keep their teeth longer,” Finkel says. “In fact, patients who have early-stage cavities often reverse that decay by flossing daily as well as brushing and maintaining good oral hygiene.”

When his patients question whether it’s worth it, Finkel says he tells them this: “It takes less than a minute, and there’s literally no downside to doing it. But if you skip it, sooner or later you -- and your dentist -- will notice a difference.”