New research suggests that fluoridation of water supplies may reduce the risk
of fracture. In a separate report, water fluoridation has been linked to a reduction
in dental caries but with an increase in fluorosis.
Ms Kathy Phipps (school of dentistry, Oregon Health Sciences university, US)
and colleagues studied 7,129 women aged at least 65 years to investigate previous
reports that exposure to fluoride increased fracture risk.
They found that women who had been exposed continuously to fluoridated water
supplies had significantly higher bone density at the lumbar spine, femoral
neck and trochanter but that it was significantly lower at the radius than in
women who had had no exposure to fluoride. Women continually exposed to fluoridated
water also had a lower risk of hip and vertebral fracture. Women with mixed
exposure to fluoride tended to have bone density values that lay between the
other groups and their risk of fracture was no different from that of women
with no exposure.
The authors say that “long-term exposure to fluoridation may reduce the
risk of fractures of the hip and vertebrae,” and that fluoridation might
be “one of the most cost effective methods for reducing the incidence of
fractures related to osteoporosis” (British Medical Journal 2000;321:860).
UK report
A Government-commissioned review published by the NHS Centre for Reviews and
Dissemination on October 6 says that adding fluoride to drinking water decreases
the incidence of dental caries but may cause mottling of the teeth in some people.
Children in areas where fluoride was added to drinking water had, on average,
2.25 fewer decayed, missing or filled primary/permanent teeth compared with
those in non-fluoridated areas and the incidence of dental caries was reduced
by 15 per cent. However, the review also says that there is an increase in fluorosis
(mottling of the teeth) in areas of fluoridation and that, in an area where
fluoride is used at a level of 1 part per million, 12.5 per cent of people would
have fluorosis that might be aesthetically “concerning”. An association
with fluoridation of drinking water and adverse events, such as cancer, bone
fracture and Down’s syndrome was not found.
A summary of the findings appears in the British Medical Journal (2000;321:844)
and the full report is available on the internet at www.york.ac.uk/inst/crd
or from the CRD Publications office (tel 01904 433648), cost £20.