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Evaluating vitamin D status. Implications for preventing and managing osteoporosis and other chronic diseases
Jean-Claude Souberbielle1, Gérard Friedlander, André Kahan
1Laboratoire d'Explorations Fonctionnelles, Hôpital Necker-Enfants Malades, Paris V University, France. jean-claude.souberbielle@nck.ap-hop-paris.fr
Abstract:
Recent studies have added new dimensions to the fund of knowledge on vitamin D. In addition to the classic role of vitamin D in preventing rickets and osteomalacia, a preventive effect against osteoporotic fractures has been convincingly established, and abundant evidence suggests a role in preventing malignancies and autoimmune diseases. Serum 25-OH-vitamin D assay is a simple test for evaluating vitamin D status. However, recent review articles indicate that current reference ranges for serum 25-OH-vitamin D are too low. An appropriate lower normal limit may be between 50-100 nmol/l (20-40 ng/ml). Standard supplement dosages may fail to provide concentrations above this range.
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