What Percentage of Americans Floss Daily?

About 30 to 35 percent of American adults report flossing every day, a figure that has barely budged in over a decade. National survey data from 2011 through 2014 pegged the rate at roughly 32 percent, and a more recent analysis tracking trends through 2020 found only a modest, statistically insignificant uptick to about 35 percent after adjustments. That means roughly two out of every three adults in the country do not floss on a daily basis, despite decades of public health messaging urging them to do so. The reasons behind that gap, and the question of how much it actually matters, turn out to be more interesting than the number itself.

How Stable Is That Number?

You might expect that with more dental awareness campaigns, better products, and widespread access to information, daily flossing rates would climb over time. They haven’t, at least not in a meaningful way. A study published in the Journal of the American Dental Association examined nationally representative data spanning 2009 through 2020 and found that the prevalence of daily flossing went from about 29 percent to about 35 percent across those years. That looks like growth on paper, but after the researchers controlled for factors like age, sex, race, income, and education, the increase was not statistically significant.¹ In other words, flossing behavior in America is essentially flat. The earlier snapshot, using NHANES data from 2011 through 2014, placed daily flossing at about 32 percent, with roughly another third of adults saying they never floss at all.²

These numbers come from self-reported surveys, and that matters. People tend to overstate healthy behaviors when a researcher is asking. If a third of Americans say they floss daily, the true number is almost certainly lower. The difficulty of measuring flossing behavior reliably has been a persistent thorn for researchers trying to study it: frequency is self-reported, and there is no practical way to gauge how well someone flosses when they do it.

Who Flosses and Who Doesn’t

Flossing follows predictable socioeconomic patterns. Research going back decades has shown that people with higher incomes and more education are more likely to floss, brush thoroughly, and visit the dentist regularly.³ The NHANES-based studies confirm the same pattern in recent data: daily flossing rates are higher among women than men, among older adults compared to younger ones, and among people with higher education levels.²

This disparity is not just about access to dental floss, which is inexpensive. It reflects broader patterns in preventive health behavior. People who are more likely to see a dentist regularly, eat nutritiously, and exercise are also more likely to floss. The habit tends to cluster with other health-conscious behaviors, making it difficult to tease apart flossing’s independent contribution to health outcomes in observational studies.

Children’s oral hygiene habits, including early exposure to flossing, are strongly shaped by parental behavior. A cross-sectional survey found that maternal education and parents’ own oral hygiene practices were the strongest predictors of whether children adopted good habits.⁴ So the socioeconomic gradient in flossing isn’t just about adults making choices; it’s partly set in motion during childhood.

Why Most People Skip Flossing

If you’ve ever resolved to start flossing every night and abandoned the effort within two weeks, you’re the norm, not the exception. A study in the Journal of Dental Hygiene surveyed both habitual and non-habitual flossers and found that the biggest barriers weren’t about pain or cost. They were about routine. Two-thirds of non-habitual flossers agreed with statements like “flossing is not a habit of mine,” “I just forget to floss sometimes,” and “flossing is not part of my oral care routine.”⁵ The next most common complaints were practical: gums bleeding and difficulty reaching certain teeth.

That finding reshapes the conversation a bit. For most people, the problem isn’t skepticism about flossing’s benefits or an unwillingness to invest the time. It’s simply that flossing hasn’t been anchored into a daily routine in the way brushing has. Brushing feels automatic for most adults; flossing feels optional. And optional habits tend not to survive.

Building a Flossing Habit That Sticks

Researchers in behavioral psychology have specifically studied what makes a flossing habit take hold. One finding stands out: people who flossed immediately after brushing, rather than at a separate time, formed stronger habits and were still flossing more frequently at eight months.⁶ Linking flossing to an existing behavior, what psychologists call “habit stacking,” seems to give it staying power. The existing brushing routine serves as a cue, and the flossing piggybacks on the behavioral momentum you already have.

A separate randomized trial found that people who made a concrete plan specifying when, where, and how they would floss outperformed a control group at both two and eight weeks. At eight weeks, the planning group was flossing about four times per week on average compared to about three in the control group.⁷ One extra flossing session per week may not sound dramatic, but over months and years, the cumulative difference in plaque removal and gum health adds up. The takeaway is practical: if you want to become a flosser, pick a specific trigger (like right after evening brushing), decide exactly where you’ll keep the floss, and be explicit about the sequence. Vague intentions to “floss more” tend to evaporate.

Does Flossing Actually Work? The Complicated Evidence

This is where the story gets contentious. In 2016, a widely circulated Associated Press investigation pointed out that the evidence supporting flossing was surprisingly weak, and the U.S. government quietly dropped flossing from its Dietary Guidelines. The resulting media frenzy, sometimes called “Flossgate,” led many people to conclude that flossing was useless. The reality is more nuanced.

A systematic review in the Journal of Dental Research looked at whether flossing reduces cavities between teeth. It found that professional flossing of children’s baby teeth on school days for nearly two years reduced cavity risk by about 40 percent. But self-performed flossing by young adolescents over two years showed no reduction at all. And no trials of self-performed flossing in adults could be identified.⁸ That last point is worth pausing on: the reason the evidence for adult self-flossing is weak is partly because we have almost no rigorous trials testing it. Absence of evidence is not evidence of absence, though the distinction tends to get lost in headlines.

The picture is somewhat similar for gum disease prevention. A systematic review of flossing’s effect on plaque and gingivitis found that most studies did not show a clear benefit for floss on clinical measures, and concluded that routine instruction to use floss was not well supported by the available evidence.⁹ That’s a striking conclusion, but it reflects more about the state of the research than about the physics of removing food and bacteria from between your teeth. The trials were generally short, small, and relied on people accurately reporting that they actually flossed.

Critics of the “flossing doesn’t work” narrative have pointed out a fundamental measurement problem. Flossing effectiveness in trials is assessed by self-report at best, with no actual measurement of flossing skill or thoroughness. Asking someone whether they flossed tells you nothing about whether they did it correctly, for how long, or whether they reached the back molars where problems tend to develop. It’s a bit like studying whether exercise prevents heart disease by asking people whether they moved their body today without measuring intensity, duration, or type.

What the Long-Term Data Actually Show

While randomized trial evidence for self-flossing is thin, observational studies that follow people for years paint a more favorable picture. A study of older adults found that those who reported flossing had significantly less periodontal disease than non-flossers, fewer cavities, and fewer missing teeth at baseline. Over a five-year follow-up, flossers lost an average of about one tooth, while non-flossers lost about four.¹⁰ That’s a substantial difference, though the usual caveat applies: people who floss regularly tend to take better care of their health overall, so it’s difficult to attribute the entire benefit to flossing alone.

A separate study examining long-term adherence to preventive dental behaviors, including flossing, found that people who consistently practiced preventive care retained more teeth over time, and that long-term adherence conferred greater benefits than short-term efforts.¹¹ In other words, flossing for a month before your dental appointment probably doesn’t do much. But the cumulative effect of years of daily interdental cleaning may be considerable, even if the short trials researchers rely on can’t easily capture it.

Flossing and Inflammation Beyond the Mouth

One area of research that has attracted serious interest is the connection between oral hygiene and systemic inflammation. The logic is straightforward: the gums are highly vascular tissue, and chronic gum disease allows bacteria and inflammatory molecules to enter the bloodstream. That low-grade, persistent inflammation has been linked to cardiovascular risk and other chronic conditions.

A study using NHANES data found that participants who reported not flossing had significantly elevated levels of C-reactive protein (CRP), a marker of systemic inflammation, even after the researchers adjusted for other variables.¹² A separate study in rural adults found independent associations between self-reported dental hygiene and several markers of systemic inflammation, including CRP and fibrinogen, after controlling for body weight and cholesterol.¹³

These are observational findings, not proof that flossing directly prevents heart attacks. The relationship between oral health and cardiovascular disease is still being untangled, and it’s possible that flossing is simply a proxy for an overall health-conscious lifestyle. Still, the inflammation connection gives biological plausibility to the idea that what happens in your gums doesn’t stay in your gums.

Alternatives to String Floss

Part of the reason only a third of Americans floss daily may be that string floss is genuinely annoying to use. It requires manual dexterity, can be painful for people with tight contacts between teeth, and is difficult to maneuver around the back of the mouth. The good news is that string floss is not the only option for cleaning between teeth, and some alternatives perform better in head-to-head comparisons.

Interdental brushes, those tiny bottle-brush-shaped picks that slide between teeth, have consistently outperformed floss in plaque removal. A clinical trial found that an interdental brush removed significantly more plaque than floss and produced a greater reduction in probing depth after six weeks.¹⁴ An earlier study comparing three regimens found that a toothbrush plus interdental brush left less plaque on proximal surfaces than a toothbrush plus floss, which in turn was better than a toothbrush alone.¹⁵ A Cochrane systematic review of interdental cleaning devices found low-certainty evidence that interdental brushes may reduce gum inflammation more than floss at one and three months.¹⁶ The catch is that interdental brushes only work if you have enough space between your teeth for the bristles to fit; people with very tight contacts may still need floss or another tool.

Water flossers have also gained popularity, and there’s some evidence behind them. A systematic review found that in four studies comparing the two, water flossers reduced whole-mouth plaque more than string floss, and were particularly effective at reaching difficult proximal surfaces.¹⁷ Water flossers can also be easier for people with braces, dental bridges, or arthritis in their hands. They’re more expensive than a spool of floss, but for many people the lower effort translates to more consistent use, which matters more than any marginal difference in per-use effectiveness.

The broader point is that the best interdental cleaning tool is the one you’ll actually use. If string floss sits in your drawer untouched, switching to an interdental brush or water flosser that you use four or five times a week is a clear upgrade over perfectly effective floss that never leaves the package.

The Environmental Angle

One dimension of the flossing conversation that rarely comes up in dental offices is environmental impact. Most conventional dental floss is made from nylon or PTFE (the same material as Teflon), coated in wax, and packaged in plastic dispensers. Floss picks, those single-use plastic handles with a short strand of floss stretched between prongs, are particularly wasteful. A study assessing the environmental footprint of various interdental cleaning aids found that floss picks had the largest environmental impact in 13 out of 16 categories measured.¹⁸

If you’re looking to reduce waste, interdental brushes with replaceable heads and refillable floss containers made from silk or plant-based fibers are now available from several brands. Water flossers produce no disposable waste beyond the electricity they use. None of this should be the primary consideration in how you clean your teeth, but for people who already care about sustainability, it’s worth knowing that the most common flossing products aren’t especially eco-friendly and that greener alternatives exist without sacrificing function.

Why Kids Almost Never Floss Well on Their Own

Parents often wonder when to start flossing their child’s teeth and whether it’s realistic to expect kids to do it themselves. The systematic review on flossing and cavities sheds some light on this. When a trained professional flossed children’s teeth on school days, cavity risk between teeth dropped by about 40 percent. When young adolescents were left to floss on their own, there was no detectable benefit at all.⁸ The implication is that skill and consistency matter enormously, and children generally lack both. Most pediatric dentists recommend that parents floss their child’s teeth (or at minimum supervise closely) until around age ten or so, when fine motor control is developed enough for the child to manipulate the floss effectively.

Parental modeling also matters. As noted earlier, children’s oral hygiene behaviors are strongly linked to their parents’ own practices and knowledge.⁴ A parent who flosses in front of their child is doing more for that child’s future dental health than a parent who simply tells the child to floss. The habit, or lack of it, is partly inherited through behavior rather than genetics.

What Dentists Recommend Versus What the Evidence Strictly Shows

There is a real tension between clinical recommendations and the research base. Most dentists and dental hygienists continue to recommend daily flossing, and professional organizations haven’t backed away from the advice. Their reasoning is partly biological common sense: food debris and bacterial biofilm accumulate between teeth where a toothbrush can’t reach, and removing that material should reduce disease risk. The fact that short-term trials of self-flossing have produced unimpressive results doesn’t necessarily mean the practice is useless; it may mean the trials are too short, too small, or too reliant on self-reported behavior to capture what’s really happening.

Meanwhile, the long-term observational data, like the study showing that older flossers lose far fewer teeth over five years, align with what clinicians see in their practices. Patients who clean between their teeth tend to have healthier gums and fewer cavities at check-ups. Whether that’s because of the flossing specifically or because flossers take better overall care of their mouths is an open question, but from a practical standpoint, the advice to clean between your teeth daily remains sensible. The strongest version of the “flossing doesn’t work” argument isn’t that cleaning between your teeth is pointless. It’s that string floss may not be the most effective or realistic tool for most people to accomplish it, and that alternatives like interdental brushes deserve a more prominent place in the conversation.