Fluoride, a naturally occurring mineral, has been added to drinking water for decades in areas where natural levels are low in an effort to combat tooth decay. Water fluoridation occurs in around 25 countries, according to the UK government, and affects around 6 million people in England, largely in the West Midlands and the North East. Among the areas currently considering introducing the approach are County Durham, Sunderland, South Tyneside and Teesside. But while water fluoridation is supported by all the UK’s chief medical officers, it has proved controversial. Additionally, many studies examining the impact of water fluoridation were conducted before fluoride toothpaste became a household staple. Now researchers say that while water fluoridation appears to bring benefits, they are much smaller than previous research suggested. “We know of a number of different areas looking at implementing water fluoridation, so it’s a very live issue at the moment,” said Dr Michaela Goodwin, senior researcher on the Catfish study, from the University of Manchester. The team, who published their findings in the journal Public Health Research, focused on two areas of Cumbria, one without water fluoridation and one where fluoridation had only recently been reintroduced. In both areas, they recruited children who were around five years old when fluoridation restarted in parts of the county in 2013, and therefore had no previous exposure to fluoridated water – as well as babies conceived after that time point. The experts looked at the baby teeth of the younger group at ages three and five and the newly erupted adult teeth for the older group at ages five, seven and 11. Results from 1,444 children in the younger cohort revealed that 17.4% of those living in areas with fluoride had decayed baby teeth, compared with 21.4% for those in areas without water fluoridation. After taking into account factors such as age, gender and deprivation, the team found that the odds of decay for those in the water fluoridation group compared to the non-fluoridation group were 26% lower. There was no clear evidence of an effect in the 1,192 older children. While the team says this may suggest an important role for fluoride exposure in utero, they add that there may not have been enough time for cavities to develop in adult teeth. Archie Bland and Nimo Omer take you to the top stories and what they mean, free every weekday morning Privacy Notice: Newsletters may contain information about charities, online advertising and content sponsored by external parties. For more information, see our Privacy Policy. We use Google reCaptcha to protect our website and Google’s Privacy Policy and Terms of Service apply. The team added that the number of teeth that were damaged, missing or filled was lower in the fluoridated areas for both younger and older children, suggesting lower caries rates. The researchers say that further analysis suggests that water fluoridation is cost-effective – although this did not take into account any organizational costs. However, the study found no evidence that water fluoridation narrows the disparities in dental health between wealthier and poorer communities, suggesting that other measures should be considered. The group also says the younger group should be assessed at age 11 for fluorosis – a condition where teeth become discoloured. Professor Mike Kelly, a senior member of the research team from the University of Cambridge, said the new data would help those considering whether to add fluoride to water. “They can now make that decision based on the most up-to-date information, not 40 years of data,” he said. Eddie Crouch, chairman of the British Dental Association, said ministers must act to prevent tooth decay. “From water fluoridation to supervised brushing in schools, they have tried and tested policies that can save money and improve oral health,” he said. “The only thing missing is the will to implement them.”
