Fluoride FAQ’s

The most frequently asked questions about water fluoridation are answered below.


What is fluoride?1

Fluoride is the ion that comes from the naturally occurring element, fluorine. Fluorine is never encountered in its free state in nature because it combines with other elements as fluoride compounds in the earth. Water dissolves these compounds, creating fluoride ions. Fluoride is present in all water sources, including the oceans.

What is water fluoridation?

All water supplies have some natural fluoride in them and the water fluoridation process just involves adding or removing fluoride to the level that protects dental health. It does not involve adding anything to the water that is not already there. There is no chemical difference between fluoride present naturally and that which is added to the water supply.

What are the benefits of water fluoridation?

Drinking fluoridated water increases the resistance of teeth to decay, resulting in fewer cavities. This means fewer fillings, fewer extractions, fewer visits to the dentist and lower dental bills – resulting in better smiles, fewer dentures and less pain and suffering. Fluoridation will help to reduce the number of school or working hours or days that are lost due to dental problems or visits to the dentist.

Fluoridation will also help in the prevention of aesthetic problems associated with decay, especially in the front teeth, problems with discomfort and problems with self-esteem. Fluoridation also indirectly reduces orthodontic problems.

This benefit applies to all teeth (baby and adult) and to all age groups in our community. All teeth, at all ages, benefit as the fluoridated water has a continuous topical action.

Despite the availability of other sources of fluoride (tablets, drops, toothpaste, professional applications), water fluoridation is still shown to be the most appropriate means of reducing tooth decay in the twenty first century. The magnitude of the fluoridation benefits has decreased in recent decades, but they are still in the range of a 20-40% reduction in tooth decay in fluoridated areas.

There is ample evidence that if water fluoridation ceases, the rate of tooth decay increases despite the use of fluoride toothpaste and supplements. The decay rate decreases again when fluoridation is re-introduced.

A community that fluoridates its water today will have teeth with approximately half as many cavities in 10 years’ time.

If I live in a non-fluoridated area, what amount of fluoride supplement should I take?

Fluoride tablets or drops should be used according to the following guidelines proposed by the Dental Health Committee Discretionary Fluoride Panel of the National Health and Medical Research Council. 

Daily fluoride supplements are to be used ONLY in cases where the natural fluoride content of your drinking water supply is less than 0.3 mg per litre. 

If you are not sure whether you water supply is fluoridated, check with a local dentist or your local water supply authority.

Daily Fluoride Dosage (in milligrams) by Age Group

Who benefits from water fluoridation?

People of all ages benefit from water fluoridation.

Is water fluoridation ‘Mass Medication’?

No. Fluoridation is simply the adjustment of the level of a substance already found in all drinking water supplies to provide a major public health benefit.  The Centers for Disease Control in the US named water fluoridation as one of the top ten public health measures of the 20th century.  

Are there any general health side effects?

No. Drinking optimally fluoridated water is not harmful to human health.

Has the issue been fully investigated in Australia?

Water fluoridation has been investigated many times in Australia, with all investigations finding fluoridation effective in reducing levels of tooth decay, and more importantly to be safe.

Who supports fluoridation?

Water fluoridation is supported by the World Health Organisation, the Australian Dental Association, the Australian Medical Association, the National Health and Medical Research Council, and dozens of health authorities in Australia and overseas.

How cost-effective is water fluoridation?

Water fluoridation is the most cost-effective and socially equitable method of tooth decay prevention for all members of a community.

The cost varies with the size of the population fluoridated, but a lifetime of fluoridation is likely to cost less than a single dental filling.

How does fluoride stop tooth decay?

Fluoride is incorporated into tooth enamel, making the enamel more resistant to the bacterial acid attacks that cause decay. Fluoride also enhances remineralization of weakened tooth surfaces, and in high concentrations can kill bacteria which cause decay.

How did water fluoridation begin?2

In the early 1900s, a dentist in the small town of Colorado Springs, Colorado noted that most local people had brown staining on their teeth, but very little tooth decay. Research eventually linked both the staining and the reduction in tooth decay to the level of fluoride in the water supply. Further research showed that a fluoride level of one part per million in the water supply strengthened teeth without causing staining, leading to the town of Grand Rapids, Michigan being artificially fluoridated in 1945. A dramatic reduction in tooth decay was noticed within a few years, and other towns and cities across the world soon followed their example. In 1953, Beaconsfield near Launceston became the first Australian town to be fluoridated, and all Australian capital cities except Brisbane followed in the 1960s and 70s. In 1964, Townsville became the largest Queensland city to fluoridate its water supply, and studies since have shown children in Townsville to have significantly fewer cavities than children in Brisbane. Large numbers of studies over the last fifty years have shown conclusively that fluoride strengthens teeth against decay without causing harmful effects. Major health authorities across the world have consistently supported water fluoridation and continue to do so.

How does fluoride work?3

Fluoride acts in a number of ways to strengthen teeth and make them more resistant to tooth decay. Originally it was thought that the benefits of fluoride were only systemic, ie fluoride being built into a child’s developing tooth enamel, making the enamel more resistant to the acid that causes tooth decay. This would have meant that only people exposed to fluoridated water as a child could benefit from water fluoridation. We now know that while some of fluoride’s effect is systemic, most is a topical effect, ie fluoride applied directly to the tooth surface and strengthening tooth enamel. Remember the famous early 1970s fluoride toothpaste ads with Mrs Marsh? “Just like the liquid gets into the chalk”. “Tough teeth, Mrs Marsh!” Topical fluoride can not only stop the development of tooth decay, but also make the enamel more resistant to future acid attacks. It also helps by reducing the amount of acid produced by the bacteria in your mouth. Drinking fluoridated water several times a day is the ideal way to give your teeth a quick fluoride treatment.

Why do I have to swallow fluoridated water if most of the effect is a topical one?4

For a few reasons. 1. While most of the fluoride effect is topical, a systemic effect still occurs, and enamel with built-in fluoride is still more decay resistant. 2. Fluoride from fluoridated water is found in saliva and provides a wonderful, low concentration fluoride treatment for your teeth. 3. Because it’s the safest, most cost effective way to gain the benefits of fluoride.

What is dental fluorosis?5

Excessive fluoride intake while teeth are forming can result in dental fluorosis, a discolouration of teeth. This can occur through high levels of naturally occurring fluoride in drinking water, or ingesting large amounts of fluoride in toothpaste or other fluoride products. Depending on the fluoride intake, dental fluorosis can appear as small white flecks, or in more severe cases as larger yellow or brown stains. Most cases of dental fluorosis are very minor, and virtually invisible.

Is water fluoridation the best way of providing fluoride?

The benefits of fluoride can be provided in many forms, including fluoridated water, salt, milk, tablets and drops. Many countries, particularly in Europe, that have elected for practical, legal or political reasons not to introduce water fluoridation have encouraged the use of fluoride in other forms. While these are still beneficial, the safest and most cost effective method, with the greatest reduction in tooth decay is seen when teeth are exposed to frequent, low concentrations of fluoride as in water fluoridation. The Centers for Disease Control and Prevention state: “Although other fluoride-containing products are available, water fluoridation remains the most equitable and cost-effective method of delivering fluoride to all members of most communities, regardless of age, educational attainment, or income level.” Another landmark study by the University of York (September 2000) reviewed 3200 research articles and concluded that: “water fluoridation has an effect over and above that of fluoridated toothpaste and other sources of fluoride.”

Is water fluoridation a form of medication?6

Fluoride is a naturally occurring nutrient already found in the water, and is used by your body to strengthen teeth and bones. In 2003, the British Medical Association endorsed the addition of vitamins, minerals and nutrients to various foods, noting that many more children and adults would otherwise suffer deficiencies in basic nutrients. In Australia , for example, we add vitamin B1 to flour, vitamins A & D to margarine, as well as folic acid and other nutrients to most breakfast cereals. Water fluoridation simply supplements the level of fluoride found naturally in the water supply and should be considered no differently.

Doesn’t water fluoridation just benefit children?

No. Because of the mainly topical effect of fluoride, people of all ages and backgrounds will benefit. With better dental care, older Queenslanders are now keeping their teeth longer. As we age, many factors can result in less saliva, a condition known as “dry mouth”. The risk of tooth decay increases with dry mouth, particularly on the softer root surfaces. When fluoride is in the mouth, the teeth become much more resistant to decay. Fluoridated water is the safest, most effective, and least expensive way to reduce tooth decay in children and adults. For example, a 2002 New Zealand report on Preventive Dental Strategies for Older Populations noted that “fluoride was the most important preventive measure available against decay for this group.”

Is fluoride poisonous?

Toxicity is related to the dose of a substance rather than merely exposure to the substance itself. Many substances (eg chlorine, iodine, fluoride, iron, salt, vitamins A & D, antibiotics, painkillers, oxygen, and even water) can be dangerous at very high levels, but beneficial and even essential at low levels. Fluoride is a naturally occurring substance, and even after increasing the amounts of fluoride to optimal levels, the level in drinking water is less than one part per million. In 1993, the US Agency for Toxic Substances and Disease Registry stated: “When used appropriately, fluoride is both safe and effective in preventing and controlling cavities.”

What about the chemicals used in fluoridating water supplies? Are they safe?

The compounds most commonly used for fluoridating water are sodium fluoride and fluorosolicic acid, chosen because they dissolve completely in water and break down into harmless compounds, leaving none of the original chemical. Queensland’s fluoridated towns (Townsville, Mareeba, Moranbah and Dalby) all use sodium fluoride, the same substance used in the fluoride tablets many of us took as children. When dissolved in water, it breaks down into harmless sodium and fluoride ions. Large cities often use fluorosolicic acid, which dissolves in water to produce harmless hydrogen ions, fluoride ions, silica and water. The fluoride ions in artificially fluoridated water are identical to those already found naturally in the water. The facts: In 2002, the UK’s Medical Research Council noted concerns “related to the chemicals that are added during the fluoridation process, and to indirect effects such as increased leaching of lead from pipes and aluminium from cooking utensils and altered uptake or toxicity of these substances…” and found “no evidence for any significant health effects of this type…”

Is the fluoride used in artificial fluoridation any different to that already found naturally in the water?

Anti-fluoridationists have often suggested that fluoride occurring naturally is different to that from artificial fluoride compounds, that absorption of fluoride could be lower in hard water (because calcium in high concentrations can bind to fluoride and reduce its absorption) and that fluoride from artificial chemical is absorbed at nigher amounts that naturally occurring fluoride. The UK Department of Health commissioned the University of Nottingham to investigate these claims, and their report “Bioavailability of fluoride in drinking water – a human experimental study” was released in 2004. It found “no evidence for any differences between the absorption of fluoride ingested in artificially fluoridated drinking water and in drinking water in which the fluoride is present naturally at fluoride concentrations close to 1 part per millions”. Nor did they find any evidence for difference between the absorption of fluoride from hard and soft waters at these fluoride concentrations.

Is water fluoridation cost effective?

Yes. The savings in dental treatment costs to a community by providing water fluoridation are substantial. It has been calculated in the United States that the lifetime cost per person of providing fluoridated water is less than that of a single filling. In 2002, Queensland Health commissioned an independent report into the cost effectiveness of water fluoridation. This 2002 Impact Analysis of Water Fluoridation stated that if all Queensland towns over 5000 people were to be fluoridated, the expected cost benefit to the state over a thirty year equipment lifespan would be more than $1 billion (at 2002 figures). In 2002, the Victorian Health Minister stated that “…every dollar invested in fluoride saves over $30 of dental treatment. The cost of dental treatment in Victoria is over $600 million each year. In the past 25 years fluoridation has saved the Victorian community nearly $1 billion in avoided dental costs, lost productivity and saved leisure time.” In speaking about Sydney’s water fluoridation, the New South Wales Chief Health Officer in 2002 reported “a significant dental health benefit, by reducing dental caries, along with the associated savings in the cost of treatment.”

Will water fluoridation harm the land or marine environments?7

The possible environmental impact of fluorides has been studied for decades. The World Health Organization and the UK’s Royal College of Physicians have both concluded that water fluoridation does not cause fluoride pollution or harm the environment and a very recent investigation in America agreed. This latest assessment quotes studies showing that damage to aquatic life is possible only at much higher levels than that found in optimally fluoridated water. It reinforces the message that fluoride is a naturally occurring substance already found in land and water. Damage to the marine environment is highly unlikely since the level of fluoride in river water is low, and the fluoride level in seawater is already much higher than that found in fluoridated water supplies. All Australian capital cities except Brisbane have been fluoridated for up to forty years, with minimal harmful effects to the environment noted.

Does water fluoridation increase the risk of bone disease or fractures?

A 1999 Australian review of the scientific literature stated: “Water fluoridation both at levels aimed at preventing dental caries and, possibly, at higher naturally occurring levels appears to have little effect on fracture risk, either protective or deleterious, at a population level.” “There is no evidence for either an osteoporosis risk or benefit from water fluoridation.” (NH&MRC, 1999) In 2000, a similar review in the British Medical Journal also concluded that: “…long term exposure to fluoridated water does not increase the risk of osteoporotic fractures among elderly people.” They noted that previous studies claiming a link between water fluoridation and hip fractures had not taken into account the potential confounding effect of other factors known to be associated with fractures, such as oestrogen use, smoking, and bodyweight. Studies that did take these confounding factors into account predictably found no link between fluoridation and hip fractures. All Australian capital cities (except Brisbane) have been fluoridated for decades and have not seen an increase in bone fractures or other ill effects.

Does water fluoridation cause cancer?8

The National Cancer Institute in the United States says very clearly that there is no evidence linking water fluoridation to any form of cancer. National Cancer Institute fact sheet The Centers for Disease Control and Prevention stated that studies to date have produced “no credible evidence” of an association between fluoridated drinking water and an increased risk for cancer. The American Cancer Society agrees; they also support water fluoridation.

Does water fluoridation cause asthma?9

No. Along with other leading health authorities, the American Academy of Allergy, Asthma and Immunology has supported water fluoridation. Not surprisingly, since asthma patients often experience more tooth decay and erosion, health authorities in Australia and overseas recommend the use of fluoride to strengthen their teeth. Supporting websites: Child Youth Health , South Australia University of Maryland Medicine

Does fluoridated water cause any other disease or medical condition?

One of the world’s leading health authorities, the Centers for Disease Control and Prevention has strongly endorsed water fluoridation. In 1999, they stated: “Early investigations into the physiologic effects of fluoride in drinking water predated the first community field trials. Since 1950, opponents of water fluoridation have claimed it increased the risk for cancer, Down syndrome, heart disease, osteoporosis and bone fracture, acquired immunodeficiency syndrome, low intelligence, Alzheimer disease, allergic reactions, and other health conditions. The safety and effectiveness of water fluoridation have been re-evaluated frequently, and no credible evidence supports an association between fluoridation and any of these conditions.” The British Medical Association says: “…there is no convincing evidence of any adverse risk to human health by the introduction of water fluoridation. Evidence through scientific studies shows that fluoride in water, at or around one part per million, does not have any effect on the health of the body other than reducing decay in teeth. This view is supported by the World Health Organisation, the Royal College of Physicians, and the British Dental Association, among others.” The world’s major health authorities and specialist medical organisations have repeated this view for many decades. Australians have now been drinking fluoridated water for over fifty years, with the only noticeable effect being significantly healthier teeth.

Could I be allergic to fluoride?10

Fluorides are found in all plants, food and water, and there have never been any proven cases of allergy to fluoride.

Can fluoridated water affect people’s behaviour?

A seven-year New Zealand study comparing the behaviour of children in fluoridated and non-fluoridated communities predictably found “no association between exposure to fluoridated water and a large range of measures of child health and behaviour…” Source: Shannon FT, Fergusson DM, Horwood LJ. Exposure to fluoridated public water supplies and child health and behaviour. NZ Medical Journal 1986;99(803):416-8.)

Will fluoridated water taste or smell different?


Shouldn’t we be concentrating on improving people’s diets and reducing sugar intake rather than just looking at water fluoridation?

The Australian Dental Association and Australian Medical Association have been advising people for decades to live healthier lives, eat a balanced diet and reduce their sugar intake. This will continue. The introduction of water fluoridation is just one part of improving people’s dental health and general health.

What do the world’s major health authorities say about water fluoridation?11

Water fluoridation has been one of the most widely studied and endorsed public health measures of all time. World Health Organisation : “Fluoridation of water supplies significantly improves dental health…” and “…fluoridation of water supplies, where possible, is the most effective public health measure for the prevention of dental decay.” Centers for Disease Control and Prevention : “Fluoridation of community drinking water is a major factor responsible for the decline in dental caries (tooth decay) during the second half of the 20th century…” They also describe the fluoridation of drinking water as one of the “10 Greatest Public Health Achievements in the 20th Century.” International Association for Dental Research : “…taking into account that over 50 years of research have clearly demonstrated its efficacy and safety; and noting that numerous national and international health-related organizations endorse fluoridation of water supplies; fully endorses and strongly recommends the practice of water fluoridation for improving the oral health of nations.” United States Food and Drug Administration : “Public health measures, such as fluoridation of drinking water and consumer education on proper dental hygiene, have helped bring about a decline in cavities in the past 50 years.” United States Surgeon General : “Community water fluoridation remains one of the great achievements of public health in the twentieth century – an inexpensive means of improving oral health that benefits all residents of a community, young and old, rich and poor alike.” The British Medical Association : “Fluoridation of water is an effective public health strategy for reducing tooth decay in the population. The evidence accumulated over many years shows fluoride is highly protective to the teeth of children, and is very safe. Water fluoridation is one of the most effective ways of reducing tooth decay in the community. Not only does water fluoridation reduce tooth decay and consequently the number of extractions needed, but it also brings the added and welcome benefit of a reduction in the number of general anaesthetics administered to children. Evidence through scientific studies shows that fluoride in water, at or around one part per million, does not have any effect on the health of the body other than reducing decay in teeth. This view is supported by the World Health Organisation, the Royal College of Physicians, and the British Dental Association, among others.” United States Public Health Service : ” The PHS report concluded that fluoride has substantial benefits in the prevention of dental caries. Numerous studies have established a clear causal relation between use of fluoridated water and the prevention of dental caries…” and “… fluoridation of water is the most cost-effective method (of providing fluoride) and provides the greatest benefit to those who can least afford preventive and restorative dentistry…” Public Health Association of Australia : “Water fluoridation has been demonstrated to be effective in preventing tooth decay”…and…”should continue to be regarded as a safe and effective public health measure.”

Does my water filter remove fluoride?

Reverse osmosis filters and distillation remove most fluoride from water, but common charcoal and ceramic filters do not.

How much fluoride is in fluoride toothpaste?

Most children’s toothpaste contains between 400 and 500ppm (parts per millions). One part per million is the equivalent of one milligram per litre. Adult toothpastes usually contain between 1000 and 1100ppm, although some can contain up to 5,000ppm.

Who should use fluoride toothpaste?

Regardless of the presence or absence of water fluoridation, everyone should be encouraged to brush their natural teeth with fluoride toothpaste.

How much fluoride should I give my child?

Given at optimal levels, fluoride can strengthen teeth and help prevent tooth decay. The correct amount of fluoride to give your child depends upon his or her age and whether or not the local water contains fluoride. Your dentist is the best person to advise you on the amount of fluoride needed to meet your child’s needs.