The Holidays are Here — Interesting [and timely] Article on Sugar and Dental Health


What and how we choose to eat and drink, as well as toothbrushing and flossing and many other factors influence the risk of developing dental caries (tooth decay). Understanding, preventing and managing tooth decay requires addressing all the contributing factors together.

Our teeth are undeniably important. Adults usually have 28 in the mouth including incisors, canines, premolars and molars. Teeth crowns are comprised of three layers:

  • Enamel which is the hard, mineralised surface – the important first barrier
  • Dentine which is a partly porous mineralised connective tissue layer
  • Pulp which is the soft centre of the tooth containing blood vessels and nerves

Dental decay can occur when teeth are coated in a dental plaque that has bacteria which make acids from fermentable carbohydrates, including starch and sugars. If this occurs over a period of time, cavities develop and eventually infection if the cavities remain untreated.

Below are some evidence-based facts and advice from dental health experts regarding the range of contributing factors for dental caries and how best to manage these to ensure happy healthy teeth:

Types of food

  • All fermentable carbohydrate (including sugars and starch) containing foods and drinks have the potential to encourage the growth of cariogenic bacteria.
  • Foods that stick to teeth, or sit in the mouth for longer can increase the risk.
  • Some carbohydrate-containing foods may contain protective factors such as milk proteins, calcium and phosphates. However while these decrease the risk they do not remove it completely.

Frequency of eating

  • Frequency of consumption of fermentable carbohydrate foods including sugars and starches may be more important than the amounts eaten.
  • Constantly snacking and/or sipping (on any type of food or drink) upsets natural protective mechanisms in the mouth and results in increased frequency of contact between carbohydrates, plaque and teeth, which increases the risk of damage.
  • It is recommended to give teeth a rest between meals and snacks (for around 2 hours), to allow the natural protective buffering of acids and repair of teeth by saliva.
  • Saliva assists in washing foods away from teeth, and neutralises acids, but also re-mineralises teeth and repairs minor damage caused by plaque acids.
  • Chewing sugar-free gums stimulates saliva production and the sugar-alcohol based products like xylitol can also help to protect teeth.

Oral hygiene

  • Regular brushing with a fluoride containing toothpaste and flossing removes dental plaque and decreases the risk of acids being made when eating and drinking.
  • Sharing food and drinks can transfer plaque bacteria especially in infants and toddlers.  Parents should take care when children’s teeth are erupting to not share spoons and toothbrushes.

Professional Advice

  • It is important to visit a dentist or dental therapist regularly to check for problems and to get preventive treatment.
  • Dental professionals can advise about other factors that increase risk of dental decay including medical conditions and many medications.


  • Dental professionals recommend that people of all ages use regular fluoride toothpaste when brushing teeth.
  • Fluoride slows down the softening of dental enamel by acid and speeds up the rehardening by saliva.
  • Both the New Zealand and Australian Dental Associations support water fluoridation as an evidence-based, cost-effective, equitable and safe means to help protect against tooth decay.
    • Tooth decay has many risk factors including genetics, general health, diet, oral hygiene and access to fluoridation
    • Any fermentable carbohydrate, not just sugar, can lead to the build up of plaque
    • The frequency at which carbohydrates are consumed is of greater importance than the amount consumed


Originally Published in

Contribution by Professor Bernadette Drummond, School of Dentistry, University of Otago and former independent advisor to the Sugar Research Advisory Service.

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