Cheng et al's article on fluoridation of water supplies provides a welcome opportunity to restate our view that fluoridation has reduced the burden of dental disease and offers the potential to address persistent inequalities in oral health.1 As with other health measures, safety should continue to be monitored and the ethical dimension discussed.

We first address the doubts expressed about the Department of Health's objectivity. The Department of Health, in 1999, commissioned the University of York to undertake a systematic review of fluoridation.2 The York team considered 735 research studies that met their relevance criteria and found no conclusive evidence of a causal …