Slaying sacred cows: is it time to pull the plug on water fluoridation?

Water fluoridation continues to be a contentious public health policy. Recent moves to introduce schemes in England raise important questions about the use of evidence in public policy. Of particular concern is how evidence is used for public health policy-making purposes. This article reviews some of the key debates about water fluoridation and examines the way evidence has been promoted and used. The background to water fluoridation is discussed and also key ideas about how evidence influences policy. While traditionally the problem of evidence is characterised as one where policy makers either accept or ignore evidence, a central concern of this article is where poor evidence is promoted by professionals and accepted by policy makers. The article then examines the evidence on the effects of water fluoridation. Drawing on the idea of the ‘Gold Effect’, the article shows how deeply held beliefs about public health actions shape not just policy but also the application of evidence itself by professionals and researchers.