Fluoride in Water: A Comprehensive Guide for UK Residents

Fluoride is a naturally occurring substance that is found in both tap water and bottled water. Whilst fluoride has been added to toothpaste to prevent dental decay since the 1890s, the addition of fluoride to water supplies remains controversial. In this blog, we look at some of the factors for and against water fluoridation and explore how fluoride can be tested and removed.

The History of Fluoride in Tap Water

Fluoridation is the practice of adding fluoride to public water supplies to prevent tooth decay. Fluoridation was first introduced in the United States in the 1940s and has since been adopted by many other countries around the world.

The idea of fluoridating water supplies to prevent tooth decay was first proposed in the early 20th century by a dentist named Frederick McKay. In the early 1900s, McKay noticed that many of his patients in Colorado Springs had brown stains on their teeth. After conducting research, McKay discovered that the brown stains were caused by high levels of fluoride in municipal water supplies. However, he also noticed that the people with stained teeth had fewer cavities than those with white teeth.

McKay concluded that fluoride could have a beneficial effect on dental health. He began to advocate for the addition of fluoride to water supplies to prevent tooth decay and later, in the 1940s, fluoridation became widespread in the US.

In the 1950s, the UK was also experiencing a dental health crisis. Many people suffered from tooth decay, and dental health services were struggling to cope with the demand. The government was under pressure to find a solution to this problem.

In 1955, a government-appointed committee recommended that fluoridation of drinking water should be considered as a means of preventing tooth decay. This was based on McKay’s earlier research in the United States and other countries that had shown that adding fluoride to drinking water could reduce the incidence of tooth decay.

Ever since fluoridation was initially proposed there has been considerable opposition to the idea from some quarters. Some people were concerned about the safety of fluoride, while others argued that it was a violation of individual choice to add a substance to drinking water without consent. Despite opposition, the UK government passed the Water Fluoridation Act in 1963. This act allowed local authorities to add fluoride to drinking water supplies, provided that they had consulted with local residents and that the level of fluoride added was within safe limits (1.5 parts per million).

The first water fluoridation scheme in the UK was introduced in Birmingham in 1964. The scheme was controversial, with many residents opposing it. However, it was also seen as a success, with a significant reduction in tooth decay rates among children in the city. Other local authorities in the UK later began to introduce their own fluoridation schemes. By the 1970s until today, around 10% of the UK population is receiving fluoridated water, with most of these schemes located in the Midlands and the North East. There are no plans to introduce new fluoridation schemes at present.

Why the Opposition, is Fluoride Safe?

While proponents argue that fluoridation can help prevent tooth decay and improve dental health, opponents argue that it may have adverse health effects.

In the UK, the benefits of adding fluoride to drinking water are widely recognised, with numerous studies demonstrating that it is an effective way to prevent tooth decay and improve dental health. The National Institute for Health and Care Excellence (NICE) and the UK Department of Health and Social Care both recommend water fluoridation as an effective and cost-effective way to improve dental health.

"We believe that water fluoridation is the single most effective public health measure there is for reducing oral health inequalities and tooth decay rates, especially amongst children. We welcome these proposals and believe they represent an opportunity to take a big step forward in not only improving this generation’s oral health, but those for decades to come." – Dr Nigel Carter, Oral Health Foundation

The most common concern about fluoridation is that it may cause harm to human health. Some people in the UK remain concerned about the potential health risks of water fluoridation. Individuals and groups argue that fluoride may be linked to health problems such as cancer, thyroid disease, and neurodevelopmental disorders such as ADHD, although these claims are not supported by strong scientific evidence.

Others simply believe that water fluoridation violates their right to choose what they consume and that they should be able to opt-out of fluoridated water.

The World Health Organisation (WHO) has recommended that the optimal level of fluoride in drinking water should be between 0.5 and 1.5 parts per million (ppm), some studies have shown that levels up to 4 ppm are safe.

Why Might Fluoride Be Dangerous?

Whilst many people in the UK are supportive of fluoridation, there is a minority who believe that adding fluoride to drinking water can be dangerous to human health. Some of the alleged dangers of fluoride include damage to the brain, kidneys, thyroid, bones, and teeth. While there is some scientific evidence to suggest that excessive exposure to fluoride can lead to health problems, the majority of current research supports the safety and effectiveness of water fluoridation.

One of the main concerns about fluoride in drinking water is dental fluorosis, a condition that can cause discoloured or pitted teeth. Severe cases of dental fluorosis are extremely rare, and the levels of fluoride added to drinking water are generally well below the threshold that would cause this condition. Another concern is the potential for fluoride to accumulate in the body over time, leading to health problems.

There are also concerns that fluoride may have adverse effects on the brain and nervous system. Some studies have suggested that high levels of fluoride exposure may lead to lower IQ scores in children, but these studies have been criticized for methodological flaws and have not been replicated in other studies. The consensus among public health organizations and medical experts is that water fluoridation is safe and does not pose a significant risk to brain function or development.

In rare cases, exposure to high levels of fluoride can lead to skeletal fluorosis, a condition that affects the bones and joints. However, this condition is almost unheard of in areas where water fluoridation is used, as the levels of fluoride are carefully regulated to prevent overexposure.

What Are the Benefits of Fluoride?

The main benefit of water fluoridation is that it helps to prevent tooth decay. Fluoride works by strengthening tooth enamel and making teeth more resistant to acid erosion. This helps to prevent cavities and other dental problems, particularly in children and adolescents who are more vulnerable to tooth decay. Studies have shown that water fluoridation can reduce the incidence of tooth decay by up to 35%, and it is considered one of the most effective ways to improve dental health. By preventing tooth decay and reducing the need for dental treatments such as fillings and extractions, water fluoridation can help to reduce the burden on the NHS and save money in the long term.

Another benefit of water fluoridation is that it helps to reduce inequalities in dental health. Tooth decay is more common in areas of social deprivation, and water fluoridation can help to level the playing field by providing access to fluoride for all members of the community, regardless of their income or social status. This helps to ensure that everyone has an equal chance of maintaining good dental health. A 2022 publication by the Office for Health Improvements and Disparities (OHID) and the UK Health Security Agency (UKHSA) reported that children and young people in areas in England with higher fluoride concentrations were up to 63% less likely to be admitted to hospital for tooth extractions due to decay than those in areas with low fluoride concentrations.

Several studies have shown that the levels of fluoride used in water fluoridation are safe and do not cause harm to human health. In the UK, the levels of fluoride added to water supplies are carefully monitored and regulated to ensure that they remain within safe limits.

In addition to preventing tooth decay, fluoride has been shown to have other health benefits. Studies have suggested that fluoride may help to prevent osteoporosis, a condition that affects bone density and can lead to fractures and other health problems. Fluoride has also been shown to have antibacterial properties and may help to prevent other types of infections.

Fluoride in Drinking Water, UK Regulations

In the UK, the fluoridation of drinking water is regulated by the Water Industry Act 1991, which gives water companies the power to add fluoride to their water supplies. Before a decision to fluoridate the water supply can be made, a public consultation process must be undertaken. This involves informing the local community about the proposed fluoridation and giving them the opportunity to provide feedback and raise any concerns they may have. Until recently, local authorities have been responsible for proposing and consulting on new fluoridation schemes, variations, or terminations. The Health and Care Act 2022 transfers this power to Central Government.

The levels of fluoride added to the water are carefully monitored and regulated by the Drinking Water Inspectorate (DWI), which is responsible for ensuring that the water supply is safe and meets the necessary quality standards. The DWI sets strict limits on the levels of fluoride that can be added to drinking water, to ensure that they are safe and do not cause harm to human health. The current UK guideline level for fluoride in drinking water is 1.5 parts per million.

The water companies are required to regularly monitor the levels of fluoride in their water supplies and report the results to the DWI. If the levels of fluoride are found to be outside of the permitted range, the water company must take immediate action to correct the problem.

Is My Water Fluoridated?

Fluoride occurs naturally in water from some parts of the UK. Additionally, some water companies are required by local health authorities to operate fluoridation schemes for some or all of their water supplies, these are:

• United Utilities
• Northumbrian Water
• Anglian Water
• Severn Trent Water
• South Staffordshire Water

Fluoride testing

Whilst it is possible to test water at home using DIY test strips, these are generally not that useful and are imprecise. Public water supplies generally contain less than 1ppm of fluoride so a test strip that is calibrated in increments of 0, 4, 10, 25, 50, and 100 ppm will be of little help. Reading the colours of these strips and comparing them against a chart can be subjective.

Independent laboratory testing services offer a much more accurate testing option. By sending a small sample of your water to our laboratory we can analyse your water sample accurately for fluoride using sensitive methods such as ion chromatography. For those who are concerned about their fluoride level, we recommend our Fluoride Water Test, or for a more comprehensive analysis of multiple contaminants, our Standard Test.

Should Households Remove Fluoride From Water?

The weight of scientific research suggests that fluoride in water at the appropriate concentration is safe. The World Health Organization (WHO) and the British Dental Association (BDA) both recommend the use of fluoride in drinking water as a public health measure. The Centre for Disease Control and Prevention (CDC) in the United States also considers water fluoridation as 'one of the ten great public health achievements of the 20th century'.

What should you do if your water test positive for high levels of fluoride? If households have concerns about potential health issues such as skeletal fluorosis or simply believe that they should have the right to choose whether they consume fluoride, then they may wish to remove fluoride from their drinking water by distillation or by using water filters.

Filtering Fluoride

Many of us in the UK have become accustomed to using activated-carbon-based water filters to remove chlorine and improve drinking water taste. However, whilst these filters are effective at removing chlorine and some heavy metals, they are not effective at removing fluoride.

Distillation is an effective way of removing fluoride (and most other things) from tap water, these work by boiling water and collecting the steam, which is then condensed back into liquid. The distillation process is effective but requires significant amounts of energy and is therefore expensive to operate. Many people report that distilled water has an unappealing taste.

There are two filtration methods that are also effective at removing fluoride from water.

• Reverse Osmosis - These filters use a semi-permeable membrane to remove impurities from water, including fluoride. Reverse osmosis filters are highly effective at removing fluoride, with some models capable of removing up to 99% of fluoride from water. However, they can be expensive to operate and require regular maintenance.
• Activated Alumina - These filters work by adsorbing fluoride onto the surface of alumina beads. Activated alumina filters are effective at removing up to 90% of fluoride from water, but they can be expensive and require frequent replacement.

The Bottom Line

Fluoride is found naturally in drinking water in some parts of the UK and is added to drinking water in other parts. Ever since fluoride was first added to UK drinking water in the 1960s, drinking water fluoridation has been controversial and subject to debate.

Most of the scientific evidence suggests that water containing levels of fluoride that are less than the UK limit of 1.5 parts per million is safe to drink and has a positive effect on our health.

Anyone concerned about the level of fluoride in their tap water can test their water with a Fluoride Water Test from our independent water testing laboratory and where required, fluoride can be removed from water using some types of water filter.