20 Apr
April 20, 2023
Marzyeh Parvizi


It might sound silly or insignificant whether you brush before or after breakfast but it is actually quite important for a number of reasons and if you do a search on Google you will see up to 10 pages of varying opinions for one view or the other each putting convincing arguments  across.

Those that say after breakfast argue that brushing will remove the food that is metabolised by bacteria in the mouth which causes tooth decay.  They add that if left on the teeth the food stays on until lunch or even until the evening meal or until they brush their teeth before going to bed.

Brushing before breakfast on the other hand is reported to remove the bacterial plaque from your teeth before it has time to metabolise the food to cause tooth decay and it is further argued that brushing your teeth before breakfast means you have removed the terrible tasting bacteria from your mouth enabling you to taste your food better.

It is worth looking at the available evidence to decide when how and for how long we should brush our teeth.  Dental decay results from the fermentation of food debris by the dental plaque to produce acids that lead to the breakdown of teeth and the formation of cavities. This acid response is present for up to an hour after the food is eaten generally until the saliva in the mouth neutralises this to normal levels.   The introduction of Fluoride toothpaste is accepted as the number one reason for the reduction of dental decay throughout the world. Fluoride prevents dental decay by preventing the demineralisation or softening of the hard tooth substance and promoting its re-mineralisation or hardening of this mineral content of the teeth.  Teeth are in a constant cycle of demineralisation and remineralisation depending on the presence of acids and saliva in the mouth. Demineralising acids produced by bacteria that metabolise food or those ingested in the form of foods or drinks such as fruit juices are counteracted by the remineralising effect of saliva and fluoride in the mouth.

When brushing teeth before breakfast this build-up of dental plaque is minimised thereby reducing the possible acid response from the oral bacteria when they metabolise the foods eaten at breakfast.  In addition to that brushing with a fluoride toothpaste prior to breakfast means that there is plenty of fluoride within the mouth to prevent demineralisation and promote remineralisation of the enamel and dentine of the teeth  at a time when it has maximum impact assuming the mouth was not rinsed out with water after the brushing of the teeth.

However, brushing the teeth after breakfast means that the response of the oral bacteria to the metabolism of the food and their production of acids has already taken place and the teeth have already been softened by the drop in pH in the mouth to acidic levels below 5.5 which is termed the critical pH where it is proven that dental tissues are demineralised or softened. By brushing after breakfast the loss of tooth substance by erosion from acids is further enhanced by tooth brush and acid abrasion where the tooth substance is simply abraded away much faster as it is already softened by the acid. The presence of fluoride in the toothpaste will not be enough to prevent the demineralisation of the teeth  and will not help promote remineralisation due to the overwhelming presence of factors against its action.

Personal preferences will eventually dictate one’s brushing habits with those brushing before breakfast wanting a nice minty fresh taste in their mouth prior to eating while those that brush afterwards site their inability to taste their food due to the presence of the toothpaste taste as the main reason for their choice. From a scientific point of view, I am convinced that brushing for at least two minutes before breakfast is best and I advise all my patients to brush before breakfast with fluoride toothpaste but I also tell all my patients to consider washing their mouth with water only after breakfast to get rid of the food debris left behind so that it does not stay on the teeth all day. This flushing action further reduces the effect of acid on the teeth thereby returning the pH of the mouth to normal levels quicker.  After breakfast is also a good time to consider the use of a fluoride rinse which will further promote the remineralization or hardening of the teeth at a time when it can stay on the teeth for a long period before any more food or drink is consumed later on in the day.

This article was prompted by many of our patients who believed that it was better to brush after breakfast and also by a local teacher in Wimbledon that taught my daughter to brush after breakfast even though I had informed her to do it before. However, even when daddy is a dentist the teacher knows best to a small child!

It is worth looking at the available evidence to decide when how and for how long we should brush our teeth.

Get in touch

We’d love to hear from you. Please fill out this form.
Thank you! Your submission has been received!
Oops! Something went wrong while submitting the form.