Abstract
In a double-blind trial with monofluorophosphate (25 mg fluoride per day) given to 460 aged persons (237 treated, 233 control) for eight months no difference was observed in height, admission to hospital, or mortality. Fractures and exacerbation of arthrosis were more frequent in the fluoride group. Vertebral x-ray films showed no difference. The free ionized fluoride levels in the plasma of the fluoride-treated group were still twice as high two months after treatment ended. Fluoride treatment in the prophylaxis of osteoporosis is not recommended unless there is simultaneous measurement of plasma ionized fluoride levels.