Water fluoridation is the adjustment of fluoride in drinking water to a level that helps protect teeth against decay. Fluoride does not alter the taste or smell of water.
In Victoria, the maximum level of fluoride in drinking water is 1 milligram per litre (mg/L), or 1 part per million (ppm), as recommended by the World Health Organization (WHO). As a comparison, the amount of fluoride in children’s toothpaste is 400-500 ppm and regular toothpaste is 1,000 ppm.
Fluoride is a naturally occurring compound found in plants and rocks. Sea water has approximately the same level of fluoride as in community fluoridation programs. It is also found at very low levels in almost all fresh water. Naturally occurring fluoride can be found at a beneficial level in some local water supplies.
How fluoride works
Tooth decay occurs when acid corrodes the outer surface of the tooth. Mouth bacteria produces this acid from sugary food and drinks. Fluoride helps to strengthen the tooth’s mineral structure. It acts like a repair kit, repairing the early stages of tooth decay before it becomes permanent.
Benefits of fluoridation
Fluoridation helps protect people of all ages from tooth decay, from the young to the old.
Water fluoridation is a fair way of delivering the benefits of fluoride to the community, regardless of individual age, education, income or motivation.
Many studies and reviews have confirmed the effectiveness of water fluoridation.
Researchers from the Australian Research Centre for Population Oral Health (ARCPOH) have presented study results examining the effectiveness of water fluoridation on children’s dental health. This study spanned four Australian states - Queensland, Victoria, Tasmania and South Australia. The study found that:
- children of 5 and 6 years of age who have lived more than half their lives in fluoridated areas have 50 per cent less tooth decay in their baby teeth, compared to children who have not lived in fluoridated areas
- children who are twelve and thirteen years old who have lived more than half their lives in fluoridated areas have 38 per cent less tooth decay in their adult teeth, compared to children who have not lived in fluoridated areas.
Water fluoridation is not just for children. A recently published study was based on data collected from the National Survey of Adult Oral Health 2004-06. Dental examinations of 5,505 adults from around Australia found significantly less decay in adults who drink fluoridated water.
Prevention is still necessary
Tooth decay in Australian children has reduced dramatically, thanks in part to water fluoridation and fluoride toothpaste, but since the mid-1990s decay levels have been rising.
By the age of six, more than half of Australian children have already suffered from tooth decay. This may be due to changes in diet and people drinking more soft drinks. It is important to maintain recommended fluoride levels so that tooth decay does not increase significantly.
Tooth decay is still a significant problem in Victoria. In 2013-14, more than 4,400 children under the age of 10, including 193 two-year-olds and 694 four-year-olds, had general anaesthetics in hospital to treat of dental decay.
In Victoria, 95 per cent of all preventable dental admissions to hospital for children up to and including nine years of age are due to dental decay.
It is important to look after teeth throughout your life. Good dental health has a direct impact on overall health.
Severe tooth decay can affect appearance, which in turn affects self-esteem and social interaction. It can also hinder eating and chewing, affecting general health. If baby teeth are lost too early due to decay, children’s adult teeth may not develop in the correct position, creating dental complications later in life.
Preventing one permanent tooth cavity in a child may prevent not just one cavity, but a lifetime of treatment for that tooth. Each successive treatment becomes larger, more complex and more expensive.
A healthy diet, good oral hygiene, brushing with fluoride toothpaste and regular dental check-ups will help to ensure teeth and gums stay healthy. Fluoridated drinking water provides further protection.
How fluoride is added to drinking water
Fluoride is added to drinking water supplies at the water treatment plant. This process is carefully controlled and monitored. Monitoring also occurs at the tap to ensure compliance with the Australian drinking water guidelines. Fluoride plants are incorporated in each water treatment plant’s risk management plan and are managed in accordance with the Safe Drinking Water Act 2003.
Australia’s peak health body, the National Health and Medical Research Council (NHMRC), specifies sodium fluoride, sodium fluorosilicate and fluorosilicic acid as suitable fluoridation compounds
National and international support for water fluoridation
Water fluoridation is supported by many international organisations, including the World Health Organization, the World Health Assembly and the World Dental Federation. Australian national organisations supporting water fluoridation include the NHMRC, the Australian Dental Association and the Public Health Association of Australia.
The Centers for Disease Control and Prevention (CDC) in the United States includes water fluoridation in its list of top 10 public health initiatives of the 20th century, alongside immunisation, seatbelts and smoking bans.
In June 2006, ARCPOH published guidelines for Australian fluoride use. ARCPOH supports the continuation and extension of community water fluoridation, referring to it as ‘an effective, efficient, socially equitable and safe population approach to the prevention of caries [tooth decay] in Australia’. These guidelines were reviewed and endorsed in 2013.
In November 2007, the NHMRC completed a review of the latest scientific evidence relating to fluoride and health. Based on this, the NHMRC recommends artificial fluoridation as the most effective community measure preventing tooth decay. In March 2015, the NHMRC released a public statement reaffirming its support for water fluoridation.
Visit the NHMRC website to read the statement and supporting questions and answers.
Fluoridation around the world
New Zealand, Hong Kong, Singapore, the United Kingdom, Ireland, Canada and the US all have community water fluoridation.
Globally, more than 350 million people benefit from community water fluoridation programs. More than 50 million people benefit from naturally fluoridated water.
In February 2008, England’s Department of Health provided £42 million to extend water fluoridation over the next three years.
In the US, water fluoridation was initiated in 1945 and the number of communities and people who benefit from it is continuing to increase. In 2012, 74.6 per cent of the US population on public water systems – or 211 million people – had access to fluoridated water.
Due to differing technical, legal, financial or political environments, some countries such as Switzerland supplement salt or milk with fluoride.
Dental fluorosis can sometimes occur if young children have too much fluoride. It usually appears as very fine pearly white lines or flecks on the teeth. It does not affect the function of teeth.
It is the only potential adverse effect of water fluoridation and cannot develop after teeth are fully formed. Since the mid-1990s dental fluorosis has markedly reduced, mainly due to low-fluoride toothpaste for young children and increased awareness of correct toothpaste use.
Fluoride and infant formula
It is safe to reconstitute infant formula with fluoridated water. The ARCPOH guideline on infant formula states that ‘infant formula nowadays is safe for consumption by infants when using fluoridated or non-fluoridated water’.
Water fluoridation is safe
Systematic reviews from the NHMRC and health authorities around the world consistently find that water fluoridation does not cause harmful effects.
According to academic clinicians from the Department of Allergy, Immunology and Respiratory Medicine at Melbourne’s Alfred Hospital, there is no clinical or scientific evidence that fluoridation affects allergies immunities at the optimal 1 mg/L. Specifically, they state ‘ … during the past 25 years, whether in Melbourne or in the UK, we have never seen a patient with any respiratory symptoms nor any allergy like symptoms that could be attributed to fluoride at 1ppm [1 mg/L] as in our fluoridated water’.
Kidney Health Australia recommends water as the fluid of choice to satisfy thirst and has stated ‘there is no evidence that consumption of optimally fluoridated water poses any health risks to people with chronic kidney disease, although only limited studies addressing this issue are available’. Kidney Health Australia has not called for the cessation of water fluoridation. An Australian review in 2008 found there is a significant body of evidence demonstrating that optimally fluoridated water is not associated with cancer risk.
Medical specialists confirm there is no credible evidence of a link between water fluoridation and thyroid disease, stating ‘ … there is no scientifically acceptable evidence that fluoridation increases the incidence of thyroid disease’. Education and choice Governments and health professionals have a responsibility to make decisions that balance the best possible community health outcomes with individual choices. Preventing problems before they occur is vital to good public health.
Education and choice
Governments and health professionals have a responsibility to make decisions that balance the best possible community health outcomes with individual choices.
Preventing problems before they occur is vital to good public health.