Brushing Right After Eating…Bad?

man and woman brushing teeth

A recent study in dental health has turned up something very surprising. Something that flies in the face of years of oral health recommendations and lessons. What is this groundbreaking new development?

Brushing right after eating could be bad for your teeth…Earth shattering, no? While a total consensus has not been reached, many of the industry’s top professionals are in agreement with this new study. And upon further inspection, the study’s findings seem to make a lot of sense.

The Problem

Cavities as we know are caused by bacteria that metabolize sugar into acid, which then eats away at tooth enamel. Besides cavities, this acid also leads to gum disease. When we think of sugary food, we usually think of traditionally ‘sugary’ foods: candy, pastries, and the like. But any food that contains fermentable carbohydrates can be used to create acid.


So brushing away the food debris immediately would neutralize this threat, right?? It turns out it’s a little more complicated. Dr. Jeffrey M. Cole, former president of the Academy of General Dentistry, said: “What we found is that much [of] those things that cause cavities, are not only sugar-containing but they are very acidic themselves.”

Pure water has a pH level of 7, making it neutral on the acid-base scale. This is the ideal level for your mouth too. Saliva is the mechanism that helps to maintain a healthy pH. Acidic liquids like vinegar, juice, and diet soda (even when you avoid the sugar, sodas are bad) bring the pH level down. It takes some time for saliva to restore the balance.

If you brush your teeth shortly or immediately after eating, you’re scrubbing and spreading all of this acid into the tooth enamel. By trying to save your teeth, you’re actually doing half of the job for the cavity-causing bacteria.



Members involved in the study offered a few good tips to help your mouth instead of brushing:

  • One is to wait about a half an hour until you brush. This allows time for saliva to do its work and bring the pH level back up towards 7. This is a much safer level at which to brush your teeth.
  • Rinsing your mouth with water or antibacterial mouthwash can help restore pH balance. Mouthwash also targets bacteria and plaque.
  • Chewing sugarless gum stimulates salivation. The sweetener xylitol also has demonstrated health benefits for your teeth.
  • Eating cheese for similar reasons to the gum. By being chewy, it encourages salivation. Also, naturally occurring chemicals in cheese help in remineralization.



Dr. Sam Sadati is the owner and practitioner of The Sadati Center of Aesthetic Dentistry in West Palm Beach and a leader in the world of cosmetic dentistry and smile design. He is the only accredited cosmetic dentist in all of South Florida and is one of only forty dentists in the world to receive an Accredited Fellow honor from the American Academy of Cosmetic Dentistry (AACD).  Apart from creating beautiful smiles, Dr. Sadati enjoys photography, travel, and the opportunity to tell a good joke.  If you have a question or comment, dental-related or otherwise, connect with us on Facebook or Twitter. We always reply to our fans and followers!