Medical practice

Adding fluoride to water does prevent tooth decay

“Consider mass fluoridation of water, says health body," BBC News reports.

The news follows study by Public Health England providing compelling evidence that fluoridation of mains water is a safe and effective way of preventing tooth decay.

Fluoridation has been morally and ethically controversial in some quarters and has raised health concerns because it affects the water supply distributed to every home in an area and so is “unavoidable”.

Public Health England carried out the research into the impact of adding fluoride to the water supply to assess the benefits and address some of the health concerns.

The research found benefits for children’s dental health, which could in turn take pressure off NHS services.

What is fluoride?

Fluoride is a naturally occurring mineral found in water in varying amounts, depending on which area of the UK you live in. It's also found in certain foods and drinks, including tea and fish.

Fluoride’s can help reduce the risk of tooth decay (where the outer layers of teeth become damaged by acids), which is why it's added to many brands of toothpaste.

What did the report involve?

England provides a unique “test-bed” to study the effects of fluoride. This is because unlike many other developed nations, there has been no mass fluoridation of water at a national level.
Instead, individual local authorities have chosen whether they want to add fluoride to the water supply.

For example, people in Birmingham have received a fluoridated water supply for many years, while Greater Manchester’s water supply is unfluoridated.

In its report, Public Health England compared a series of health outcomes between “fluoridated” and “unfluoridated” local authorities.

What were the key findings?

The key findings of the report (PDF, 1.5Mb) were:

  • there were 15% fewer five-year olds with tooth decay in fluoridated areas than non-fluoridated areas
  • there were 11% fewer 12-year olds with tooth decay
  • there were 45% fewer hospital admissions of children aged one to four for tooth decay (mostly for extraction of decayed teeth under a general anaesthetic) in fluoridated areas than non-fluoridated areas

Does fluoridation of water pose any risks?

No significant health risks have been detected over many years in large populations who have been provided with a fluoridated water supply.

One of the most compelling pieces of evidence about the safety of fluoridation comes from the US. Around 200 million people have been exposed to a fluoridated water supply for decades and there have been no credible reports of harm.

There is a potential risk that a condition called dental fluorosis can occur, particularly if a child’s teeth are exposed to too much fluoride when they're developing.

Mild dental fluorosis can be seen as very fine pearly white lines or flecking on the surface of the teeth. Though, aside from changes in appearance, mild dental fluorosis does not cause damage to the teeth.

The report found that around one in 100 children in Newcastle (which has a fluoridated water supply) had a moderate degree of dental fluorosis.

The report concludes “water fluoridation is a safe and effective public health measure.”

NHS Attribution