the Australian Dental Association
Written by the Australian Dental Association, Sep 08, 2023
Fact Checked

Tooth decay is the most common chronic disease affecting Australian adults and children, yet it is nearly completely preventable. One way to help prevent tooth decay is by using fluoride.

What is fluoride?

Fluorides are minerals found naturally in rocks and soil, tea, vegetables, grains and water. Fluoride forms when salts from the element fluorine (a gas) combine with the minerals in rocks and soil.

The amount of fluoride found in the natural environment is generally not enough on its own to protect your teeth from decay. That is why small amounts of fluoride are often added to community water supplies, as well as to toothpaste, mouthwash, and other dental products.

How does it work?

Fluoride is particularly effective when low levels are constantly maintained in the mouth. This is best achieved through water fluoridation and constantly drinking water throughout the day.

There are a few ways that fluoride protects teeth

  • Fluoride reduces the amount of minerals that are dissolved from tooth enamel by acids produced by decay-causing bacteria.
  • Fluoride promotes tooth minerals being put back into tooth enamel in the early stages of tooth decay.
  • Fluoride stops mouth bacteria from processing sugar from food and turning it into acid which attacks the teeth.

Water fluoridation

Water fluoridation is the addition of fluoride to drinking water to strengthen and protect teeth against tooth decay. Some communities already have fluoride naturally present in their drinking water. In these communities, the fluoride is topped up to be at the recommended level to protect teeth.

Fluoridated drinking water safely strengthens everyone's teeth, from the very young to the very old. Drinking fluoridated water as a child has shown to decrease your risk of tooth decay as an adult. Water fluoridation has been found to reduce tooth decay by 26% to 44% in children and adolescents, and by around 27% in adults.

Water fluoridation began in America in 1945 and has been added to water supplies in Australian towns and cities since 1953. Beaconsfield in Tasmania became the first town in Australia with fluoridated water.

The level of fluoride in drinking water should be within the range of 0.6 - 1.1 mg/L (also known as parts per million - ppm).

The US-based Centers for Disease Control and Prevention hails water fluoridation as one of the great public health achievements of the 20th century. It has proven so effective at reducing tooth decay in children and adults that health authorities around the world such as the World Health Organization, the National Health and Medical Research Council and the Australian Medical Association strongly back its use.

Since 2017, 89% of the Australian population has had access to fluoridated drinking water.

Image: Percentage of the Australian population with access to fluoridated drinking water as of 2017.

Not all Australians have access to fluoridated community water, however DIY water fluoridation is not recommended. Read more at I cannot access fluoridated water. Should I add fluoride to my own water?

Dental fluorosis

Dental fluorosis is the appearance of white lines or flecks on the surface of teeth which happens after the consumption of increased levels of fluoride whilst the teeth are developing.

In Australia, dental fluorosis most commonly occurs in mild forms with no negative impact on oral health or appearance, and its appearance can lessen over time. For people with this condition, it is advised to follow your dentists recommendations about drinking fluoridated water and using age-appropriate fluoride toothpaste.

More information

For more information on water fluoridation, read the National Health and Medical Research Council Public Statement 2017: Water Fluoridation and Human Health in Australia.

For Australian recommendations on fluoride use, read the 2019 Australian Fluoride Guidelines.