Fluoridation of public water to prevent dental caries has been advocated for more than a half century in the UK and USA, and the benefits of optimum fluoridation for oral health have been affirmed by the US Public Health Service.1 In addition to the beneficial effects on teeth, fluoride ingestion has been shown to increase bone mineralisation, an observation that has led some researchers to suggest that long-term exposure to fluoridated water might have a protective effect on the skeleton. At least one study has shown increased axial bone density in postmenopausal women exposed to 1 mg/L of fluoride for more than 10 years.2 However, there has always been a lingering doubt about the safety of water fluoridation in relation to the skeleton. Such fears have increased recently because of several factors: consumption of fluoridated public water is increasing (in the USA between 1985 and 1993 the number of people drinking fluoridated water increased by 8% to 144 million;3 heightened concern that high concentrations of fluoride can produce fluorosis, a crippling bone and joint disorder; the publication of one randomised placebo-controlled trial of high doses of sodium fluoride (ie, 75 mg/day) that showed a significantly greater risk of non-vertebral fractures among the fluoride-treated group despite substantial increases in spinal bone-mineral density;4 and the emergence of studies suggesting that fluoridated water increases the likelihood of osteoporosis and hip fracture.5
* Original study online at https://doi.org/10.1016/S0140-6736(99)00458-4
1.Kroger H, et al. Public Health Service report on fluoride benefits and risks. MMWR Morb Mort Wkly Rep. 1991; 40: 1-8
3. Fluoridation Census. US Department of Health and Human Services. CDC, Division of Oral Health Atlanta, PHS. GeorgiaSeptember 1993. Google Scholar
4. Riggs BL. et al. Effect of fluoride treatment on the fracture rate in postmenopausal women with osteoporosis. N Engl J Med. 1990; 322: 802-809. PubMed
5. Jacobsen SJ, et al. Regional variation in the incidence of hip fracture. JAMA. 1990; 264: 500-502. PubMed
6. CauleyJA et al. Effects of fluoridated drinking water on bone mass and fractures: the study of osteoporotic fractures. J Bone Miner Res. 1995; 10: 1076-1086. PubMed.