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It starts off with the little lie. “How often are you flossing?”, your dentist asks.

“Oh, pretty much every day. Probably“, you reply.

Your dentist knows you aren’t flossing regularly. The Shakespearean tragedy that used to be your mouth protests too much. At each appointment you are lectured on how to floss like a stroke victim relearning how to walk. “First, wrap the floss around your index fingers, like this. Now, wrap the floss around a tooth and depress. Let’s try it again on the next tooth.”

Like you haven’t already been through this song and dance a few months ago. All of this has happened before. All of this will happen again.

The number of people who are flossing is fuzzy. It’s somewhere between 10 and 40 percent. The American Dental Association guesses its on the high end. But they consist of the dentists you are lying too. No one I know does it every day. It is included in the top 10 new years resolutions that Americans make and then break every January. On coach.me there are more people trying to make flossing a daily habit (72,500) than the following:

  • no smoking (9,700)
  • no drinking alcohol (25,900)
  • praying (50,100)
  • eating breakfast (45,400)
  • saving money (61,400)
  • walking (30,600)

It is only narrowly beat out by going to the gym (78,300), that perennial New Year’s resolution that packs out the gym in January and leaves it a ghost town 4 weeks later. There are 9 coaches you can hire today for $15 a week on coach.me just to help you floss your teeth regularly.

Daily flossing has struck a cord. We aspire to do it after every dental checkup. And we fail.

There are things in life that are actually hard. Running. Writing. Learning the piano. Salsa dancing. Quitting smoking. To do these things you have to make a real effort. You have to Embrace the Suck.

Then there is flossing. It doesn’t require special skills. It doesn’t require a significant time commitment. No expensive equipment. No lifetime of practicing so you can be the world’s best flosser. No selfies of you triumphantly finishing your first floss. No congratulations from your friends for quitting being a non-flosser.

Bat Boy Lives!
An actual photo of me during middle school

I used to have a mouth like Bat Boy from the Weekly World News. Teeth pointing every which way out of my gums. I had a jaw that was 20% smaller than the teeth it was supposed to hold even before my wisdom teeth came in. My mouth was a clown car – teeth cramming themselves into any gap that still had room.

Multiple tooth extractions and a few years of braces later, and I had a smile like Patrick Bateman from American Psycho. Without all the blood. At least when I wasn’t at the dentist.

A smiling Patrick Bateman from American Psycho
Dental floss. I need it for … flossing someone.

If you had braces in the 90s, you’ll remember what it was like. Before Invisalign. When braces were chunks of metal and chickenwire and rubber bands cemented to the front of your teeth. Every few weeks you would get an adjustment. This is a euphemism for something that, if it had been invented during the dark ages, would have replaced the rack as the preferred method of torture. You learn to live with constant pain. It is a headache that lasts for years. Your teeth are literally flowing on a river of flesh and bone inside your jaw.

Then there is the pure social embarrassment. Your braces are magnetized to attract food. A good percentage of what you eat will remain in your teeth for long after you have finished your meal. Your mouth will be a horror show on display every time you speak. Chunks of corn on the cob a reminder to all that you now suck at eating.

Your mouth will be a horror show on display every time you speak. Chunks of corn on the cob a reminder to all that you now suck at eating.

After years of pain, social awkwardness, and a bizarre diet that restricts you from eating anything that is crunchy, chewy, sticky, or remotely fun, the braces come off. A few hours of terror as the dentist breaks them off your teeth with an actual hammer, chisel, and pliers.

The relief is fleeting. Your life has two new horrors – the upper and lower retainer. If you had any social aspirations before this, give up now. Now the letters ‘t’, ‘d’, and ‘k’ will no longer pass your lips. Don’t worry, you still have 23 other letters to choose from. This will last at least as long as you had to wear braces. Probably longer. My dentist’s advice – “wear your retainer every day, forever“.

So after all this, you would expect that I would take exquisite care of my teeth. Nope. I spent another 15 years doing the bare minimum of brushing every day. Going to the dentist. Telling him that “of course, I floss probably nearly every day“. The bloody aftermath. The flossing lesson. The few days of following advice. The shame of repeating the cycle again and again.

Mathew Inman of The Oatmeal describes this much better than I do in comic form.

Then I discovered one simple trick that changed everything. I went to 100 percent compliance overnight. No willpower or lectures required. It’s so simple, that if I reveal it now, you’ll probably stop reading and ignore my advice. You need a bit of backstory to really understand how powerful this trick really is.


Side note: I know this article has gone viral recently as an excuse for why you aren’t going to floss your teeth. Yes, we have really poor scientific data on the efficacy of flossing. Epically bad data. The real issue here is that doing a large-scale, rigorous, double-blind, placebo controlled trial for flossing is basically impossible (or at least so expensive that no one will pay for it). So of course we don’t have Science to prove that flossing improves oral health. Your dentist and hygienist and your bleeding mouth know better. Read this before trolling about why flossing is worthless. But I digress.


There is a strange phenomenon with dental care in America. Even though nearly everyone knows that they should floss daily, nearly no one does consistently. But almost everyone brushes their teeth every day. The benefits from daily flossing are at least as important as daily brushing for keeping your teeth in your head. But everyone does one and not the other.

The reason why isn’t what you’d expect. Before 1920, most people did not brush their teeth. Then one advertising campaign changed everything.

Claude Hopkins was approached by Pepsodent to market their shiny new product. A weird new type of paste for your teeth that came in a tube, tasted like mint, and made you look like you had rabies when you used it.

Hopkins was someone that understood how to market products. He made Schlitz one of the most famous beers in America. He put Palmolive on the map. But getting America to brush its teeth was going to be his biggest challenge by far.

Before 1920, most people did not brush their teeth. Then one advertising campaign changed everything.

Hopkins grand idea was to turn the act of brushing your teeth, specifically with Pepsodent, into a daily habit.

Charles Duhigg, in his book The Power of Habit shows us that nearly 40 percent of our waking hours are spent engaged in habits. A habit is something we do on autopilot. It doesn’t require motivation or willpower. It doesn’t even require what we would traditionally think of as thinking. Habits are embedded so deep in your brain that they essentially run on autopilot. We don’t have to think about our habits. We just do them.

You likely aren’t even aware of 90% of your habits. The current science suggests that habits exist to free up our brainpower for more important things. The brain kicks habits out of the prefrontal cortex – that huge chunk of the brain that lets you do all the neat things that humans do like writing, painting, and making up excuses for why we can’t do certain things. Habits are relegated largely to the striatum, an ancient structure located deep in the more reptilian part of our brain.

We don’t have to think about our habits. We just do them.

Every human being has their own unique habits. For example:

  • After my phone vibrates, I pick it up and look at the screen.
  • After the alarm goes off, I turn it off and get out of bed.
  • When I see a puppy, I pet her on the head.
  • After I finish dinner, I turn on the TV.
  • When a commercial comes on the radio, I change the channel.
  • After I feel a craving for nicotine, I smoke a cigarette.
  • When my computer pops up a security alert, I blindly click on the close button without reading it.

Someone is actually funding a study involving fMRI brain scans for the last one. I’m not making this up.

In his book, Duhigg describes the creation of every habit as a simple, 3 step process. Cue. Routine. Reward.

  • Cue – the event that triggers the habit. The phone ringing. You seeing the puppy. The nicotine craving.
  • Routine – Your response to the cue. Answering the phone. Petting the puppy. Smoking the cigarette.
  • Reward – The immediate benefit you receive after the routine. Hearing a friend’s voice. Those cute puppy eyes staring lovingly at you. The happy squirt of dopamine in your brain from the nicotine rush.

Every habit you have today was originally formed and reinforced over time by this 3 step process.

So how did Hopkins hook America on Pepsodent? Lets look at the ad.

Pepsodent Toothpaste Advertisement from 1929

Hopkins knew that every good habit must start with a cue. He sat down with every dental textbook he could find to locate a cue to craft his Pepsodent habit. What he unearthed in his research was the mucin plaques that naturally form on everyone’s teeth. It doesn’t make your teeth yellow. You don’t need toothpaste to get rid of it. It may even help protect your teeth from bad bacteria.

Everyone gets a filmy buildup of this mucin on their teeth after a period of time. Most importantly, you can feel it with your tongue when it is there.

You know the feeling that you get after you haven’t brushed your teeth for a day? That used to be what having normal un-brushed teeth felt like every day pre-Pepsodent.

So now Hopkins had a cue to match up with his Pepsodent brushing routine – your tongue feeling the natural film on your teeth. But he didn’t have a reward. Research shows that people don’t build habits with far-off rewards like not having your teeth fall out of your face.

This is the same reason I wasn’t flossing my teeth after spending the better part of a decade having my mouth broken and repaired. The reward needs to immediately follow the routine for a habit to form. This is why cigarettes are so powerful. You get a rush of nicotine within seconds after your first puff. Bam – A huge immediate reward.

Hopkins second brilliant insight was in the creation of two simple rewards for the routine of brushing your teeth.

The first reward is obvious. Your tongue can tell that the film that used to be on your teeth is gone. His advertising campaign was to convince you that this indicates your smile is now whiter. Your brain subconsciously links the lack of film with the bright white smile from the advertisement. Instant reward.

The second reward is in the specific ingredients Pepsodent used. Other toothpastes in the era removed the film of mucin plaque just as well. But they didn’t achieve breakout success. Pepsodent specifically used citric acid and mint in their formulation. These ingredients are oral irritants. They aren’t helping clean your teeth or your gums. In fact, they make your gums tingle with irritation after you finish brushing like you rubbed them with sandpaper. It’s a pleasant sensation. But meaningless in terms of benefit.

That tingle is all the reward your brain needed to cement the habit and make it permanent.

Now every time you missed a brushing, you were reminded of it by the film buildup on your teeth (Cue). When you finished brushing your teeth (Routine), the reward centers of your brain would light up with the tingle from the irritants and the “clean feeling” from the loss of the film (Reward). With a few repetitions, Hopkins would have you hooked on brushing with the power of habit. Just like a cigarette. Except it won’t kill you. And it will keep your teeth in your head longer.

Nearly every tube of toothpaste on the market now has at least one irritant as an ingredient. Hopkins got us hooked.

Here’s the diagram Duhigg created to visualize the habit formation process:

Cue-Routine-Reward Habit Loop Diagram

With a few repetitions, Hopkins would have you hooked on brushing with the power of habit. Just like a cigarette.

With this simple habit loop of cue, routine, reward, Hopkins and Pepsodent transformed America’s teeth brushing. It’s part of our culture now. Most people can’t imagine going to bed without brushing their teeth first. We instill the habit in our children as soon as the first tooth erupts from the gumline. Baby teeth that are going to fall out in a few years anyway. We believe the habit is that important.

Unfortunately, flossing has the deck stacked against it in terms of habit formation.

First, there is there is no immediate reward for doing it. Your tongue can’t feel the benefits of flossing since it cleans areas your tongue can’t reach. Floss every day for a year, and your teeth will look exactly the same. You won’t see bulging teeth muscles growing. It won’t make you more attractive. It won’t give you more energy. It won’t make you more money. If you don’t do it, a lot of negative things will happen. Eventually. Years down the road. That’s Future Me’s problem, he’ll figure it out by then.

Second, there is an immediate punishment. Flossing is not a particularly pleasant process. Most likely, your gums will bleed if you haven’t flossed in a while. When you do something and blood starts to spurt out, it’s usually a sign to stop what you’re doing. That’s your brain trying to protect you. A negative habit forms. Bleeding is bad. If I don’t floss my gums won’t bleed.

Finally, you have to put your fingers inside your mouth to do it. You’ve been conditioned from an early age that this is inappropriate social behavior. Your hands are dirty – don’t put them in your mouth. On some level, this existing habit is fighting against you as well.

As I’ve discussed above, the only way to something effortlessly every day is to turn it into a habit. But you can’t create a habit loop without a reward. If Proctor and Gamble’s billions of dollars can’t find a way to make dental floss habit forming, chances are you won’t either.

How do you form a habit without an immediate reward? You don’t. It’s not going to work. Or at least not very effectively.

Changing habits without an immediate reward is really hard. Losing weight doesn’t have an immediate reward. Neither does eating healthfully. Or saving money. Or waking up on time. Or not smoking. Every major life change we attempt needs a habit associated with it it so we can do it without having to fall back on willpower.

If you have to rely on willpower, you are going to fail. The science is against you my friend. Willpower is a limited resource. It gets depleted. When it is depleted, our best intentions don’t matter. We will eat that pint of ice cream. Smoke that cigarette. Skip the gym. Buy something not in the budget. It happens to everyone.

If you have to rely on willpower to do something, you are going to fail.

This is the real, scientific reason why you aren’t flossing every day. It’s not your fault. Flossing will never have an immediate reward attached to it. Your brain is going to revolt every time you do it.

Here is the big secret. Are you ready for it?

The most effective way to form a habit with no immediate reward is to hijack an existing strong habit.

This is what researchers call habit stacking. You piggyback on your brain’s reward centers for an existing habit that you have down cold. When you do an activity following an strong habit in sequence, the rewards from the first habit begin to spill into the second. Over time, the immediate reward from the first habit will strongly reinforce the second as well.

In addition, the human brain loves lists. Specifically crossing items off of lists. Your brain releases a little shot of dopamine every time you cross something off of a to-do list. Just like it releases a (much bigger) shot of dopamine if you snort cocaine. The list item doesn’t even have to be written down. Finish a small task on your mental checklist of things to do, get a reward. Completing something feels good. It’s in your DNA.

You have some sort of morning routine that involves brushing your teeth. There is a high likelihood that you do something immediately after or before that is also on autopilot. For me, it is putting on deodorant. If you live in the US, chances are you put on deodorant every morning. Probably around the same time you brush your teeth. Or maybe it is taking a shower. Or combing your hair.

So how did I go from flossing once every few weeks to every morning without fail? I just wedged it in between brushing my teeth and putting on deodorant. Two existing, extremely powerful habits that I do every single day. Even if I’m rushed or on vacation, there is basically a 0% chance that I won’t do both of these things every morning, in the exact same order that I’ve done for decades.

Do you feel let down yet? Does this seem extremely anti-climactic? Sorry. This is the best advice that science has to offer. Let’s get into the details a bit since you’ve come with me this far.

The Scientific Steps to Build a Permanent Daily Flossing Habit


  1. Buy at least two rolls of dental floss. Running out before you finish building the habit will wreck the process.
  2. Pick two habits you do every day in sequence in the bathroom. Two things you do even when you are on vacation in Tahiti or hung over or possibly both. No, not that. Get your mind out of the gutter.
  3. Identify the objects associated with these two habits. If one of them is shaving, then your razor. If another is brushing your teeth, then the toothpaste.
  4. Ideally, your choice in habit-objects should be things that aren’t already on your bathroom counter. Things that you pull out of a drawer and put away afterwards are ideal. Remember – your brain loves to-do lists. Pulling something out of a drawer and putting it on the counter is list building.
  5. Pull out your dental floss and line it up with the other two habit-objects.
  6. Do the first habit as normal. Put the first habit-object away. If your first habit is brushing your teeth, put away the toothpaste in the drawer. Done! Dopamine!
  7. Pick up the dental floss. Remove a length of floss. Commit to flossing only one tooth. Do more if you feel like it, but floss at least one.
  8. Put the floss away. Feel the to-do item getting checked off. Done! Congratulations! You did it!
  9. Pick up the other habit-object and do whatever you normally do with it. Put it away in the drawer. Done!
  10. Commit to repeating this every day for the next month. Even if you are hung over on your Tahitian vacation. Make sure you pull out all 3 habit-objects from your drawer every day at the same time.
  11. When you finish a roll, add dental floss to your shopping list. Always have a backup roll on hand.

Flossing only one tooth seems like cheating. This is the magic of turning flossing into a habit. Yes, flossing only one tooth feels ridiculous. But letting yourself skip a day will put you back at 0 in habit formation.

By committing to doing this new habit every day without fail you are cementing it into your daily habits. Slowly moving it from your prefrontal cortex into your striatum. Turning it into a routine that will soon run on auto-pilot.

Note – I’m shamefully stealing this method from Stanford professor BJ Fogg. He has a great (free) online program called Tiny Habits that you can join if you want some more in-depth support and accountability. People swear by it because it actually works.

How to actually floss correctly

You’re probably flossing wrong. Don’t worry about it. Nobody really knows how to floss unless they work in a dental office.

The goal of flossing is to remove the bacteria deposits from the inaccessible regions of the teeth before it turns into plaque (once it turns into plaque, it generally can only be removed by a dental professional). Your teeth have 5 exposed surfaces where bacteria grow. Brushing hits 3 of those. The other two can only be reached by flossing.

Most people just jam the floss in between their teeth and move it around like a hacksaw. It’s entertaining and guaranteed to make your gums bleed. But it isn’t doing anything useful.

Instead, visualize using the floss like a squeegee that scrapes the edges of your teeth clean. You need to move the floss up and down vertically against each tooth face, while simultaneously being careful not to damage your tender gum tissue.

The floss should travel below the gumline on each tooth face. But it should not forcefully make contact with the gums at any point.

Here’s a quick guide on how to floss correctly


Side note: When scouring stock photo sites for this article of people flossing, I couldn’t find a single one with someone doing it correctly. The more I searched, the more horrifying it became. An endless hellscape of mindlessly smiling faces each attempting to pose with floss more provocatively than the last.


A man attempting to eat a string of dental floss
And then there’s this guy with a soulless stare who seems to think dental floss is food

Choosing the best dental floss

I’m fairly opinionated when it comes to the type of floss I use. Any floss is better than no floss. But if you want to get serious about it, here’s what I look for:

  • No flavoring. Why on earth do you want your floss to taste good? You’re not eating it, are you? Unflavored is best.
  • Minimal or no wax. Waxed floss lets you floss badly faster, but it makes it harder for the floss to pick up all that bacteria you are trying to remove. No good. You want floss that bacteria will stick to like a sponge.
  • Maximal surface area. I personally like expanding floss. Expanding floss starts out small enough to get between the tightest teeth, but puffs up to have a larger and more textured bacteria collecting surface.
  • Rough texture. With a good floss and proper form you can feel the areas of buildup between your teeth and know when have finished removing it. A rougher flossing surface will remove buildup quicker like sandpaper. This usually isn’t advertised on the box so you may have to experiment or get advice from your dentist.

GUM Expanding Floss

I use GUM Expanding Floss. I buy them in packs of 6 so I never run out.

What about water picks, easy flossers, etc?

I’ve used water picks in the past instead of flossing. And I have extremely deep pockets as a result of my previous dental work (multiple 5mm deep pockets).

My dentist has never seen any difference in the health of my gums with daily water picking. It was a waste of time and money over flossing.

Some people like easy flossers. Little pieces of plastic that are supposed to help you floss quicker. I think that easy flossers are much easier to use incorrectly than plain old dental floss. They even look like little hacksaws, which is the motion you shouldn’t be doing when you floss.

I’ve been flossing for years. Plain old cheap unwaxed dental floss works great with a few weeks of practice. Go simple, not fancy.

But I have braces! Sorry, you especially don’t get a pass. Braces, bridges, or anything else that makes it impossible to floss normally also accelerates the plaque buildup between your teeth. Buy a pack of floss threaders.

What to do next?

If you’ve read this far into a few thousand word article on flossing, you should probably do something about it.

Buy some floss. Try habit stacking for a month to make a daily flossing habit stick. Revel in smug satisfaction at your next dental appointment when your hygienist pokes and prods your gums and they don’t bleed (and you know, are actually healthy).

Read this excerpt from Duhigg’s The Power of Habit about the rise of Pepsodent and the power of habits.