Dr John Briffa has a blog. His latest post is about fluoridation. I think I agree with Dr Briffa on some points: for one thing, it seems to me that the benefits of fluoridation are often overstated; there is also the issue of informed consent. I’m uncomfortable with the idea of “mass medication” where those being medicated have not been given a choice. If people wish to avoid fluoride-supplemented water then, ideally, I think they should be free to do so. Their choice would not affect the health of others, so I would say that it should probably remain their choice (given that people in this country can choose to smoke cigarettes, drink alcohol, and ride horses, it is probably fair to point out that we, as a society, often allow people to take risks with their health and to make their own decisions in that area).
“fluoride is a potentially toxic substance, and has been linked with diverse adverse effects on health”.
Briffa links to http://www.fluoridealert.org/health/epa/index.html, which criticises EPA for allowing a level of fluoride that is dangerous – and also has a database of ill-effects arising from ingestion of fluorine. Categories include: cancer, brain, allergy, bone disease, immune system, kidney, pineal gland, respiratory, reproductive, thyroid gland, tooth decay, arthritis, gastrointestinal, and dental fluorosis. That’s one hell of a scary list. Given Briffa’s “toxic” reference and the statement regarding “diverse adverse effects on health” (and the fact that he links to them) it seems fairly safe to assume that Briffa broadly agrees with the people running the scaremongering Fluoride Alert website. For myself, I’m not sure I would put my trust in Fluoride Alert and John Briffa to tell me about the dangers of fluoride.
The Fluoride Alert website warns of an increased risk of bladder cancer in connection with fluoride. Frustratingly, they seem more likely to link to news stories or videos hosted on their site than research papers on the effects of fluoride. For example, there is no reference on their website to this paper: http://tinyurl.com/taiwan-F, which has the conclusion that “Our study does not support the suggestion that fluoridation of water supplies is associated with an increase in cancer mortality in Taiwan.”
The Centre for Reviews and Dissemination at York University conducted a review of the evidence regarding flouridation. They have a webpage which tells us that they were unable to find reliable evidence regarding fluoridation and records their concern about the misrepresentation of their work. Here. They also urge us to read the executive review – pdf. Regarding cancer and fluoridation, 18 of the 26 studies were from the lowest level of evidence, with the highest risk of bias. The conclusion includes this quote:
The evidence of a benefit of a reduction in caries should be considered together with the increased prevalence of dental fluorosis. The research evidence is of insufficient quality to allow confident statements about other potential harms or whether there is an impact on social inequalities. [My italics.]
But it does allow media nutritionists and anti-fluoride campaigners to speculate, or to overplay health concerns.
Briffa’s blog also offers this:
“it seems reasonable to consider whether there is any evidence that the practice of water fluoridation has been pushed at us (and even forced on us) as a result of commercial and political influence and agenda. For more on this, see this video featuring Christopher Bryson, a former BBC producer and author of the book The Fluoride Deception.”
Here comes the conspiracy… Christopher Bryson’s book includes the chapter heading “how the Manhattan Project sold us fluoride”, and another titled “through the looking glass”. He talks about a “silent killer [stalking us] in our ignorance” and “secret agendas” – such as that of “industry and the US military”. OMG, this isn’t an issue of public health yet to be decided either way – it’s the military-industrial complex trying to poison our babies with fluoride! Why do Alt Med practitioners like nutritionistas feel such affinity for conspiracy theorists? I mean, Briffa’s not exactly alone here.
ETA: Tony has challenged Briffa’s use of figures for fluorosis in a comment on Briffa’s blog. The claim of 1 in 2 apparently comes from a BMJ write-up of the York systematic review and Tony complains that Briffa has ignored the authors’ caveats. The BMJ paper includes this in the discussion: “The prevalence of fluorosis is overestimated by the indices used in the included studies because enamel opacities not caused by fluoride may be included.” Page 48 of the York PDF points out that:
The term ‘fluorosis’ is used throughout this report, however it should be understood that the indices used to measure fluorosis also measure enamel opacities not caused by fluoride. Hence, the levels of fluorosis described here include some amount of overestimation of the prevalence of true fluorosis. [My italics.]
The authors also discuss (on page 59 of the same PDF) the concern that:
Observer bias may be of particular importance in studies assessing fluorosis. Efforts to control for potential confounding factors, or reducing potential observer bias were infrequently undertaken. Seventy-two of 88 studies did not use any form of blinding of the assessor, and 50 of 88 did not control for confounding factors, other than by simple stratification by age or sex.
http://tinyurl.com/gbooks-Bryson – Bryson’s book The Fluoride Deception on teh Googlebooks.
I found the York refs on the Bad Science blog here: precious bodily fluids.
Backup copy of Briffa’s blog post: http://backupurl.com/cache/ck2xdv.html. Thanks are due to Skeptobot for alerting us to this resource.
H/T – Jon