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I have heard claims that it is unsafe for those with osteoporosis to drink tap water in municipalities that add fluoride to it, because it increases risks of fractures. For example:

  • Fluoridation.com

    short-term high-dose fluoride studies show the same amount of fluoride accumulates in the bones of osteoporosis patients as would be found in some people who are chronically exposed to long-term "low" doses of fluoride (such as in fluoridated areas). People with renal insufficiency, for example, can incorporate four times more fluoride into bone than an average healthy individual and would therefore be more susceptible to the long-term effects of drinking "optimally" fluoridated water than the average individual

  • Mercola.com

    Supporting this are human studies performed, given therapeutic doses of fluoride to try to prevent fractures from osteoporosis, which causes low bone density, often have found increases in fracture rates in the treated patients, even though their bone density increased.

    So, the important scientific question is whether water fluoridation can lead to high enough levels of fluoride in your bones to noticeably weaken them. A dozen or so epidemiological studies have investigated this, with mixed results. Some of them show that fairly low levels of fluoride intake can increase the risk of fractures, whereas others have found no effect.

Trying to research, I came across an older journal article from 1996 stating that studies on the general population have been inconclusive.

Data on the relationship between fluoride intake and hip fracture risk at the individual level, and data relating fluoridation to bone mineral density are required. Until these become available, the burden of evidence suggesting that fluoridation might be a risk factor for hip fracture is weak and not sufficient to retard the progress of the water fluoridation programme.

Is fluoridated water actually unsafe for those with osteoporosis?

Oddthinking
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A L
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    I'm keen to reopen this question because there are some scary claims here that deserve investigation. However, the question isn't clear, and we should make it more specific. Looking at your references, are you asking about *specifically* osteoporosis, or do you mean osteofluorosis or just a more general "weaker bones". (Mercola spends most of the time talking about bone strength, not osteoporosis.) In the title, you ask about increasing the risk of getting osteoporosis, but in the body you ask about people who already suffer it. Can you clarify what you are asking about so we can re-open? – Oddthinking Jun 15 '16 at 04:20
  • A side-issue is whether high-dose fluoride (not fluoridated water!) is an effective treatment for osteoporosis. You references suggest it helps build heavier bones, but weaker ones. That sounds like an interesting topic to explore too, but in a separate question. – Oddthinking Jun 15 '16 at 04:22
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    @Oddthinking I'm sorry, you're right. The specific claim I would like it to address is, for someone who already has osteoporosis, does fluoridated tap water put the person at higher risk for bone fractures. If you believe this could be edited as such, or irrelevant sources removed, or if there are other specifics you think should also be investigated separately, I'd be happy for you to take it as you see fit. – A L Jun 15 '16 at 04:36
  • Consider that Fosomax and similar osteoporosis drugs place many people at higher risk for bone fractures. – Daniel R Hicks Dec 26 '17 at 19:19
  • @DanielRHicks - so.... the drugs have the opposite effect that they are supposed to, and they're still on the market? – PoloHoleSet Dec 26 '17 at 21:08
  • A simplistic description of the mechanism for maintaining strong bones is that there are two sets of little PacMan gizmos wandering about inside the bones. One set eats existing old bone and the other set builds new bone. Working together they manage to keep bones rejuvenated. But they slow down as you age, and, in particular, the bone "builders" fall behind. Fosomax and similar drugs work by blocking the action of the '"eaters", with the result that bone is not regenerated and becomes more brittle. Useful if the "builders" are falling behind, but not otherwise. – Daniel R Hicks Dec 26 '17 at 22:54

2 Answers2

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There is no valid, peer-reviewed scientific evidence to support a claim of adverse effects of optimally fluoridated water on those with osteoporosis, or on anyone else. Those, who make unsubstantiated claims that "there are studies which show..." are never able to produce any such studies.

In 2013, Nasman, et al.found:

Overall, we found no association between chronic fluoride exposure and the occurrence of hip fracture. The risk estimates did not change in analyses restricted to only low-trauma osteoporotic hip fractures. Chronic fluoride exposure from drinking water does not seem to have any important effects on the risk of hip fracture, in the investigated exposure range."

-- Estimated Drinking Water Fluoride Exposure and Risk of Hip Fracture A Cohort Study P. Näsman, J. Ekstrand, F. Granath, A. Ekbom, C.M. Fored Journal of Dental Research 2013 Nov;92(11):1029-34.

Fluoride accumulation in hard tissues is not a linear constant. It is in equilibrium with plasma fluoride levels. As plasma levels decrease, fluoride is removed from hard tissues until equilibrium is once again attained. Plasma levels are determined by fluoride intake and by that amount removed from hard tissues.

Sklivvz
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Steven Slott
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  • Thank you, good answer. I think it could be bolstered by citing this meta analysis from 2015, and considered it accepted: http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0126488 – A L Jun 16 '16 at 18:07
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    Also I'm not completely comfortable with your claim that they are never able to produce studies, and you don't really seem to back that part up. The claims in the question do reference some studies, not that they are good studies, and in my further reading of a meta analysis it shows that some studies to show some correlation and others show the inverse, overall there is no correlation, but I would prefer your answer be changed in that regard. – A L Jun 16 '16 at 18:20
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Here's a data point in the opposite direction:

Fluoride has greatest potential as a therapy for osteoporosis once bone has been lost. It has been demonstrated both experimentally and clinically to stimulate bone formation directly and to increase bone mass in patients who already have osteoporosis.

At first glance, it seems disappointing and inexplicable that, after 40 years of research, fluoride is still considered an experimental drug in the United States. ... Fluoride as a naturally occurring element is difficult to patent, and this has kept major pharmaceutical companies from investing heavily in fluoride therapy despite its obvious potential.

Excessive fluoride is harmful, but so is lack of fluoride.

endolith
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