Water fluoridation is effective in preventing tooth decay overall, but there are greater benefits for children from lower socioeconomic backgrounds, University of Queensland research has found.

Professor Loc Do from UQ’s School of Dentistry, and researchers from the Institute of Science Tokyo, Japan and the University of Adelaide, conducted a study that examined Australian children’s exposure to fluoridated water and compared it to demographic factors such as socioeconomic status, parental background and geography.

“This is the first high-level scientific study that shows water fluoridation as a population strategy reduces socioeconomic inequalities in children’s oral health,” Professor Do said.

“We found while water fluoridation helps prevent tooth cavities across the board, it is more beneficial for vulnerable populations.”

Researchers analyzed oral health data of 17,500 children aged 5 to 14, which was captured during the National Child Oral Health Study (NCOHS) in 2012–2014. The findings are published in the International Journal of Epidemiology.

“Tooth decay is one of the most prevalent diseases and impacts more than 2.5 billion people globally,” Professor Do said.

“While there is a lot of scientific evidence that water fluoridation as a population strategy prevents dental cavities, there is little known about how water fluoridation impacts health inequalities—and that’s what we wanted to explore.

“We looked at the data of children who had been fully, or never, exposed to fluoridated water, so we could capture the effect of fluoride on preventing tooth decay.

“Using a unique algorithm, we then analyzed this data alongside 47 different child demographic, socioeconomic and parental factors.

Associate Professor Yusuke Matsuyama, from the Institute of Science Tokyo, said children who had been exposed to fluoridated water over their entire lifespan had dental health benefits, but those benefits were much greater for children from lower socioeconomic backgrounds.

“Children fully exposed to fluoride made up 58.1% of the group we analyzed, and we found they were more likely to have higher household socioeconomic status, lower area-level socioeconomic disadvantage, better dental health and private dental insurance,” Dr. Matsuyama said.

“But when looking at the actual benefits of fluoridated water, we found that the group to have the most benefits were more likely to be children from single-parent households, with lower household income, have parents not working, and live in socioeconomically disadvantaged areas.”

Professor Do said these results confirmed the universal impact of water fluoridation for everyone in the communities, regardless of their conditions and abilities.

“The benefits were relatively larger for those from lower socioeconomic backgrounds because those groups have poorer dental health due to multitude of factors such as access to dental care.

“These results show that water fluoridation helps reduce the gaps.”