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Fluoride Fragility

We have always known that fluoride can affect bones as well as teeth, causing osteofluorosis, which in its early stages is difficult to differentially diagnose from various kinds of arthritis.

It was claimed, however, that this disease occurred only after high doses, resulting in increased bone mass and high fluoride content of the bones. In fact, high doses were sometimes deliberately given to treat osteoporosis, a disease in which bone mass is decreased. Fluoridated water was also claimed to benefit sufferers from osteoporosis by reducing their risk of hip fracture.

Over the last two years, comprehensive studies in the US and the UK have suggested that fluoridated water, and fluoride treatment for osteoporosis, actually makes bones more fragile and liable to fracture.

A study reported in the American Journal of Epidemiology showed that women in an area with 4 parts per million (ppm) water fluoride -- the claimed maximum safe level -- had twice the hip fracture rate of, and more bone loss than, women in areas with 1 ppm water fluoride. The margin of safety of low water fluoride levels is clearly less than than fluoridation advocates claim.

It has been argued that only a weak association has been shown, and that further evidence is required before a causal connection between water fluoridation and hip fractures could be assumed. However, the inverse correlation now claimed between fluoridated water and tooth decay is actually weaker and less significant than the positive correlation now reported between fluoridated water and hip fractures.

The reductions in tooth decay claimed to be due to fluoridation sound impressive when expressed as a percentage reduction in decayed, missing and filled teeth or tooth surfaces. In fact, they are usually less than half a tooth per child -- sometimes less than half a tooth surface -- which is not even statistically significant, let alone clinically significant.

Recent rigorous, well-designed clinical studies of the side effects of fluoride treatment for osteoporosis suggest that fluoride, far from strengthening bone as expected, actually increases bone fragility and fractures. A Swiss case study concluded that there was a causal link between hip fractures and fluoride in patients with renal failure, and Indian studies reported reduced tensile strength of fluoride-affected bones.

The evidence now strongly suggests that low fluoride doses over long periods, as well as high doses for short periods, can damage bones. The belief that the amount accumulated from fluoridated water would be insignificant is now discounted by new evidence. The situation may well worsen as people reach old age after spending greater proportions of their lives ingesting low fluoride doses.

Fluoridation since the 1950s has increased the fluoride intake of millions of today's old people for up to half their adult lives. An unanswered question is: what will have been the effect on the bones of today's children by the time they reach old age.

John Colquhoun, International Society for Fluoride Research

John Colquhoun, International Society for Fluoride Research