Water flouridation has beneficial effects on child health, a new UK study has claimed.

A report by Public Health England has concluded that on average, there are 15% fewer five-year-olds with tooth decay in fluoridated areas than non-fluoridated areas in England.

When deprivation and ethnicity are taken into account, 28% fewer five-year-olds have tooth decay in fluoridated areas than non-fluoridated areas.

The study also found that on average, there are 11% fewer 12-year-olds with tooth decay in fluoridated areas than non-fluoridated areas.

When deprivation and ethnicity are into account, 21% fewer 12-year-olds have tooth decay in fluoridated areas than non-fluoridated areas, the study found.

The report said the reduction in tooth decay in children of both ages in fluoridated areas appeared to be greatest among those living in the most deprived local authorities.

In fluoridated areas there are 48% fewer hospital admissions of children aged one to four for dental caries (mostly for extraction of decayed teeth) than in non-fluoridated areas.

The report also found there was strong evidence that the rate of kidney stones was lower in fluoridated areas compared to non-fluoridated areas following adjustment for age, gender and deprivation and following additional adjustment for ethnicity.

And there was evidence that mortality rates for all causes was lower in fluoridated compared to non-fluoridated areas following adjustment for age, gender and deprivation.

The study also indicated positive effects of fluoridation on the incidence of other conditions such as Down's Syndrome and bladder cancer.

According to the Irish Dental Association (IDA), the findings are significant, in that they indicate positive public health benefits of water fluoridation.

The IDA says, along with every recognised dental representative body in Ireland, says it endorses fluoridation as a vital public health instrument.