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Timing Your Teeth Brushing

When It May Be Better to Rinse and Wait

© ClassicStock/Corbis

That colleague who always brushes his teeth after lunch in the office bathroom? A published study suggests that scrubbing immediately after eating may be doing him more harm than good. While professional opinions may vary, Delaware dentist Jeffrey M. Cole, former president of the Academy of General Dentistry, a dental advocacy group, weighs in on this topic.

Cavity Culprits

Sugary foods, particularly those that are sticky or liquid, are bad for your teeth because the bacteria or plaque on the enamel metabolizes sugars, producing acids that can lead to gum disease, inflammation and cavities. Conventional wisdom held that if you remove the food particles quickly after they were introduced into the mouth, you would reduce the instance of cavities. "What we found is that much of the cariogenic substances, those things that cause cavities, are not only sugar-containing, but they are very acidic themselves," says Dr. Cole.

Too Much Acid


Scrubbing with a toothbrush can actually encourage the process, according to a study published in the journal General Dentistry in 2004. "When you want to make etched glass, you apply an acid or an abrasive and scratch it—that is what happens if you drink a sports drink or a soda, or even wine, and brush right after," says Dr. Cole. If you wait 30 minutes, however, "the saliva in your mouth will naturally bring the acid down to a more neutral pH and not rub acidic substances in."

Rinse, Repeat


Cheese Whiz

Studies show two things people can chew to help ward off tooth decay. One, Dr. Cole says, is chewy cheese: String cheese will reduce the pH of bacterial plaque. One reason, says Dr. Cole, is that chewy things make you salivate, and proteins in your saliva will buffer acids. Also, naturally occurring chemicals in cheese "encourage the tooth to remineralize." Dr. Cole suggests: "The pairing of wine with cheese is actually a good thing, because the cheese can counterbalance the acidity of the wine."

Chewing sugarless gum is also a good option if you can't get to your toothbrush. "Some studies have suggested that xylitol, which is the sweetening agent in gum, actually has anticariogenic characteristics."


Dentists like Dr. Cole suggest brushing twice a day, for two minutes each time. If you can only do it once, bedtime is best, since that is when your mouth salivates less, allowing cavity-causing substances to take hold. Rinsing after sipping sugary drinks is always a good idea. "I'm guilty of craving a Coke now and then just like anyone else," says Dr. Cole. "But after I will go and rinse that acid and sugar out with some plain water."

Eliot Walter
Eliot Walter

$10k worth of work on my teeth this year, because I damaged the enamel on my teeth. No dentist ever gave me this advice. You might also note this is under the Health and Wellness section. The WSJ is a general news service, not just a financial rag. That said, I think the WSJ over-reports on sports.

Grand Mesa
Grand Mesa useraccountSuspended

WSJ is incapable of giving any financial advice so it's now trying dental hygiene.

William Stewart
William Stewart

I care; I found that regular brushing with toothpaste destroyed much of my enamel due to the abrasiveness. Now I only rinse,floss, and lightly brush. When you are twenty you can get away with most anything...When you turn fifty you see the results of your actions.

Mike Alan
Mike Alan user

I like to brush my teeth while peeing.

Michael Chan
Michael Chan subscriber

Who really cares?!

As long as you floss and brush your teeth, then that's all it matters.

WSJ is actually printing these articles? It should try some serious journalism instead.

Floyd Pinkerman
Floyd Pinkerman

Just another article by the Obamanation (© David Zamos) designed to tell us what to do with our mouths. Don't buy it people, this is just another attempt by the MSM to distract you from what's really going on in Syria. Impeach now!!

News at 11.

Elsamma Chacko
Elsamma Chacko

I have something to add here. Brushing teeth is not the only activity to be avoided during the 30 minutes after a meal. Any elective exercise also is to be avoided.

For many of us with metabolic disorders (overweight, obesity, pre diabetes, diabetes ...) the best time to exercise begins some 30 minutes after the first bite of a typical meal. This is the beginning point of an interval of opportunity that ends at about the 90th minute post meal. I call this period the "Exercise Window".

My experience as a physician and diabetes patient is that the safest time for elective physical activity for all of us is when the exercise window is fully open. For the metabolism challenged this is an imperative.

Healthy people may get away with exercising any time. For People with insulin resistance it is a different story; exercising before meals can mess up glucose levels (A1C) depending upon the intensity of the exercise.

Barry Schmidt
Barry Schmidt

Makes sense to me. As a retired practicing dentist, anything that will alter the production of acid by bacteria or reduce the effects of acid is a good thing. Rinsing after drinking a cola is recommended. The stuff is loaded with about 10% phosphoric acid---not good for tooth enamel. Also, for crying out loud, stay away from sugar or sugary products, such as are found in most prepared foods and canned goods. Sugar is food for bacteria; bacteria is what produces acid, via their ability to form the plaque that sticks to your teeth.


What kind of article is this? One to make us feel even more insecure about what we do (grin)...


My dentist recommended toothpaste with baking soda to neutralize the acid.

Thomas Bishop
Thomas Bishop subscriber

'Chewing sugarless gum is also a good option if you can't get to your toothbrush. "Some studies have suggested that xylitol...actually has anticariogenic characteristics."'

so chewing sugarless gum and not brushing immediately (30 minutes) after eating is optimal?

Dennis Schminke
Dennis Schminke subscriber

Twice a day here...upon waking up, and before bed. Not tied to mealtimes.

Carl Caravana
Carl Caravana

Plaque requires 24-48 hours to form on teeth, thus brushing once per day is adequate to prevent
Dental disease in healthy individuals. Twice daily brushing contributes to unnecessary wear on
Tooth surfaces.

John Beauregard
John Beauregard subscriber

Cheese sandwich and an apple for lunch?

The norm is to eat the sandwich, then the apple. The new wisdom reverses this.

Robert Mesnard
Robert Mesnard subscriber

"String cheese will reduce the pH of bacterial plaque. " Wait... what? I thought the problem was acidity. A pH that was too low... Maybe the author meant "increase"? I'm confused...

Bruce Boehnlein
Bruce Boehnlein subscriber

yeah, i 'm going to leave my desk and walk down the hall to go rinse my mouth every time i drink something. maybe i will get a spittoon

William Moss
William Moss subscriber

I'm only guessing but either the writer misunderstood or the meaning was lost when he used the term pH. I think sometimes people will use pH as a word to mean "acidic" which is technically incorrect but done nonetheless. The real message was the "chewing of cheese" produces saliva which in turn will buffer the acid raising the pH. I did like the "wine and cheese" story; it just reinforces what I do many afternoons.

Michael Berkovich
Michael Berkovich subscriber

If you are rinsing with water, you can swallow it. You don't need to rinse with moutwash every time you eat or drink. As the article says, you are just trying to get the PH in your mouth back to normal.

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