A striking new study from Queensland, Australia reveals that rates of tooth decay among primary school children have plunged following the expansion of water fluoridation programs. Researchers assessed more than 7,700 students aged 5 to 14, comparing data from 2021–2024 against older baselines in 2010–12, and found that decay in baby teeth among 5–10 year olds dropped from 49.5% to 38.8% in regions with fluoridation.

In areas newly fluoridated, improvements were especially strong; in regions without fluoride in the water, rates remained relatively unchanged. The average number of decayed tooth surfaces in that 5–10 age group also declined by about 24%—from 4.1 surfaces to 2.9.

However, the policy landscape is precarious: a number of local councils—including Gympie and Cook—recently voted to remove fluoride from their water supplies. Queensland remains a rare Australian state where local governments decide on fluoridation, meaning community-level decisions weigh heavily.

Researchers hope this contemporary, large-scale evidence will encourage more councils to re-evaluate fluoridation as a safe, cost-effective public health measure.