Fluoride – Oral Health Foundation

What is fluoride?

Fluoride is a natural mineral that is found in many foods and in all drinking water. The amount of fluoride in water varies from area to area.

What are the benefits of fluoride?

Fluoride can greatly help dental health by strengthening the tooth enamel, making it more resistant to tooth decay. It also reduces the amount of acid that the bacteria on your teeth produce.

Children who have fluoride when their teeth are developing tend to have shallower grooves in their teeth, so plaque can be more easily removed. Plaque is a thin, sticky film of bacteria that constantly forms on your teeth.

The addition of fluoride to water has been researched for over 60 years, and water fluoridation has been proven to reduce decay by 40 to 60 percent.

Where can I find fluoride?

Fluoride is found naturally in many foods and in water supplies, and is also added to some drinking water. Having 0.7 to 1.2 parts of fluoride for every million parts of water (0.7ppm to 1.2ppm) has been shown to have the best effect.

All water contains some fluoride. Your local water supplier can tell you how much fluoride is in your drinking water.

Is there enough fluoride in my water supply?

Possibly. However, only a few places have enough natural fluoride to benefit dental health. In other places it is added to water. Your water supplier will be able to tell you whether your water supply has fluoride added. The amount of fluoride added to the water will vary depending on which area you live in.

Fluoride is also in some foods and drinks, for example fish and tea. Some countries add fluoride to their table salt and milk instead of to the water supplies. One cup of tea can contain between 0.3 milligrams and 0.5 milligrams of fluoride, and if you drink it with milk your teeth will also benefit from the calcium. It is best to drink tea without sugar to reduce the risk of tooth decay even more.

What about fluoride toothpaste?

Most toothpastes now contain fluoride, and most people get their fluoride this way. Fluoride toothpaste is very effective in preventing tooth decay. The amount of fluoride in toothpaste is usually enough to reduce decay.

In areas where the water supply has fluoride added, fluoride toothpaste gives extra protection.

All children up to three years old should use a toothpaste with a fluoride level of at least 1000ppm
(parts per million). After three years old they should use a toothpaste that contains 1350ppm to 1500ppm.

Parents should supervise their children’s brushing, and use only a pea-sized smear of fluoride toothpaste until they are about 7 years old.

Spit out after brushing and do not rinse with water, so that the fluoride stays on your teeth longer. 

Should people have extra fluoride?

Children living in poorer areas where the water supplies are not fluoridated can have 5 times more decay than children living in more affluent or fluoridated areas. Research suggests that adding fluoride to the water is the best way of reducing these ‘dental inequalities’.

Your dental team can apply fluorides to your teeth. These come as varnishes or gels and are more concentrated than ones you can apply yourself, so you do not need them as often. Some adults can benefit from these applications. Fluoride varnishes can help to reduce tooth decay – especially for people with dry mouth.

Some people are more likely to have tooth decay, and the dental team may also advise using a higher-strength fluoride toothpaste for extra protection.

Are there any side effects of fluoride?

‘Dental fluorosis’ is caused by having too much fluoride when the teeth are developing. This can happen when fluoride supplements are taken by children under 7 who live in areas where the water supply is fluoridated. It can also happen when children swallow toothpaste.

What is fluorosis?

In its mildest form, dental fluorosis appears as very fine pearly white lines or flecking on the surface of the teeth. This mild fluorosis can often only be spotted by a dental expert. Severe fluorosis may lead to the enamel being pitted and discoloured.

Fortunately, severe fluorosis is rare.

Is fluoride safe?

Many reports have been published throughout the world about fluoride. After many years, the scientific conclusion is that fluoride toothpaste and correctly fluoridated water, salt and milk are of great benefit to dental health, help to reduce decay, and cause no harmful side effects to general health. Studies have not found any evidence that fluoride added to water causes harmful side effects.

People who are against fluoridation claim they have firm evidence that fluoride added to water is harmful. However, scientific analysis has not supported their claims.

Worldwide, over 300 million people drink fluoridated water supplies. Many millions more use fluoride toothpastes regularly. In the USA for example, well over half of the population have fluoridated water supplies. This has led to improved levels of dental health which in turn benefits general health.