John Colquhoun

"In 1997, the journal Perspectives in Biology and Medicine published an opinion piece, "Why I changed my mind about water fluoridation," by John Colquhoun [1]. Although the journal's stated purpose is to convey new ideas or stimulate original thought in biological and medical sciences, Colquhoun presented no new data. His paper rehashed earlier criticisms of water fluoridation, using selective and highly biased citations of the scientific and nonscientific literature [2-10].

"Colquhoun, who died in March 1999, was a dental officer in New Zealand during the 1970s and early 1980s. His writings display blatant bias in evaluating the published literature on fluoridation, criticizing any study supporting fluoridation for poor design (e.g. non-blind examinations, non-random selection of subjects and communities), while ignoring gross defects in the methods used in studies that found no caries reduction in fluoridated communities. He was the Editor of Fluoride, a magazine published by the International Society for Fluoride Research, for which he was also the Treasurer. Despite its propitious title, Fluoride is primarily a vehicle for printing articles that decry the benefits of communal water fluoridation (13 of Colquhoun's 73 citations are from this anti-fluoride publication). Colquhoun's paper is in the same genre. In it, Colquhoun states that water fluoridation is ineffective in reducing caries and that the decline in caries observed in most Western industrialized countries is not due to fluorides but rather to a vaguely described "improved nutrition." He also contends that water fluoridation is harmful to teeth (causes fluorosis) and to general health (causes bone cancer, weakens bones, affects behavior) and lacks universal endorsement. In general, Colquhoun ignores the overwhelming findings of the efficacy of water fluoridation in reducing caries prevalence, not only by failing to cite recent individual studies from various parts of the world, including Australia, Britain, Canada, Ireland, and New Zealand as well as the United States, that have reached this conclusion, but also by omitting major reviews that have cited these studies [11,12]. Instead, Colquhoun cites his own and Diesendorf's publications, which have been discredited because of significant errors, misquotations, and the use of questionable data [13]. Other reports that Colquhoun cites that supposedly do not show benefits of fluoridation failed to establish residence histories of the sample populations, used crude measurements of caries prevalence, and were based on intake of natural fluoride, the level of which is neither controlled nor monitored [14,15]." [1]