Fluoride: A toxic or therapeutic agent in the treatment of osteoporosis?

This article summarizes recent studies and is a review of the literature on the fluoride compounds and their influence on bone mineral mass. It is well known that fluoride is an important element for mineralization of body tissues. The use of topical and systemic fluoride for oral health has resulted in major reduction in dental caries, but fluoride also plays a role in bone health. Dieticians and other health professionals are advised to recommend adequate use of systemic and topical fluorides, especially in children and adolescents. Population studies as well as earlier studies of individuals exposed to fluorides indicate that doses above 30–40 mg daily can result in fluorosis, characterized by increased fracture risk. Numerous clinical studies have demonstrated increased bone mineral density in subjects treated with appropriate doses of fluoride. However, the clinical interpretation of these studies has been a matter of debate. Therapeutically, fluoride seems to be useful when the agent is started in the early stages of osteoporosis, especially in patients with intact trabecular bone. It is well established that fluoride can act as an effective stimulator of bone formation by the osteoblasts. Bisphosphonates, which can also increase bone density, act by inhibiting bone resorption by osteoclasts. As a result of this, owing to the tight paracrine association characterizing skeletal metabolism, bone formation is slowed down by the antiresorptive agents. It is of particular interest that great benefit in the treatment of osteoporoses is seen when adequate osteoblast-stimulating doses of fluorides are given in combination with antiresorptive medication, but further research is needed to substantiate this promising concept. J. Trace Elem. Exp. Med. 17:83–92, 2004. © 2004 Wiley-Liss, Inc.