The practice of adding fluoride to water started some 60 years ago, and is widely held by dentists and public health experts to have been a major factor in the improvement in dental health seen in individuals living in areas where water fluoridation is practiced. However, as I have written before, the science shows that water fluoridation is of relatively limited benefit, and has the capacity to do considerable harm ” including to our teeth!
Up until recently, the the most comprehensive study to assess the effectiveness of water fluoridation (often referred to as the ‘York study’) found that just one in six people drinking fluoridated water benefits from this practice [1]. However, drinking fluoridated water was also found to cause serious ‘dental fluorosis’, a condition in which the teeth become mottled, discoloured or even pitted due to excess fluoride.
When the York Study was published in the British Medical Journal, it triggered a flurry of letters which were critical of the conclusions drawn from it. Many letters highlighted the potentially toxic effects of fluoride (such as a an increased risk of bone fracture), and called into question the practice of water fluoridation. One of the most vocal critics of the study was Paul Connett, Professor of Chemistry at St Lawrence University in New York state, USA [2]. Professor Connett had been one of the scientific reviewers for the York study prior to its publication. In his letter calls the authors of the York study to task for not making it clear that dental fluorosis is an indication of a toxic effect of fluoride. He also raises the question of what other enzymes and proteins fluoride may causes unwanted effects in the body that are not visible to the naked eye.
Professor Connett went on to criticise the York study for downplaying the apparent link between fluoride exposure and risk of bone fracture. While the study authors conclude that there was no link between increased hip fracture in the elderly and fluoride exposure, Professor Connett shows how critical evidence of a link was seemingly ignored by the authors.
More criticism for the practice of fluoridation came from a dental surgeon in Ireland [3]. In it, the author states that 73% of the Irish water supply is fluoridated. As a country, Ireland has the sixth best tooth quality in the World. However, of the five countries with better dental quality, four do not fluoridate. Also, in Ireland, individuals living in non-fluoridated areas have more decay-free teeth than those who drink fluoridated tap water! The author of this letter also points out that fifty per cent of the Irish population has dental fluorosis, and asks whether causing a dental disease in half of the population to reduce tooth decay by a supposed 15% is acceptable.
Despite considerable doubts about the ‘benefits’ and concern about the harm it may cause, the British Dental Association (BDA) continue to bang the drum for this practice.
So, I’m wondering whether members of the BDA might think of a recent study which, as the York study before it, casts serious doubt over the wisdom of adding fluoride to water supplies. This reviewed appropriate studies published between January 2001 and June 2006. Like the York study, this review found that dental fluorosis affects about half of those drinking fluoridated water [4].
And again, as with the York study, they could find little evidence that water fluoridation was effective in preventing dental decay.
For instance, the authors of the review report that: In most European countries, where [water fluoridation] has never been adopted, a substantial decline [75%] in caries prevalence has been reported in the last decades” and “Several epidemiological studies conducted in fluoridated and non-fluoridated communities suggest that [fluoridation] may be unnecessary for caries prevention.” The authors add, in reference to studies which assessed the effects of stopping fluoridation, that: “after the cessation, caries prevalence did not rise, remained almost the same or even decreased further.”
More information about the potential hazards of fluoride can be found on the website http://www.fluoridealert.org. Those of a hardy disposition might also like to look at this interview of Christopher Bryson, author of book entitled ‘The Fluoride Deception’.
http://fluoridealert.org/bryson.htm. The book and this interview some of the political issues surrounding the highly dubious practice of water fluoridation.
References:
1. McDonagh M, et al. Systematic Review of Water Fluoridation BMJ 2000;321:855-859
2. Connett P. Letter BMJ 2001;322:1486
3. MacAuley D. Letter BMJ 2001;322:1486
4. Pizzo G, et al. Community water fluoridation and caries prevention: a critical review. Clin Oral Investig. 2007 Feb 27; [Epub ahead of print]
