Vitamin D - From Essentiality to Functionality

Centre on Aging and Mobility, University of Zurich and City Hospital Waid, University Hospital Zurich, Switzerland.
International Journal for Vitamin and Nutrition Research (Impact Factor: 0.85). 10/2012; 82(5):321-326. DOI: 10.1024/0300-9831/a000126
Source: PubMed


Vitamin D is essential in bone and muscle health. Severe deficiency (25-hydroxyvitamin D serum levels < 25 nmol/l) can result in rickets and osteomalacia, fractures, myopathy and falls. All recent recommendations on vitamin D agree that children and adults should reach a target 25-hydroxyvitamin D range of at least 50 nmol/l (threshold for normal vitamin D status) and 50 % of the population may be below that threshold. A vitamin D intake of 600 to 800 IU per day as recommended today will prevent about 97 % of children and adults from vitamin D deficiency. Notably, a higher 25-hydroxyvitamin D threshold of more than 60 nmol/l is needed for optimal functionality, fall and fracture in adults age 65 and older.

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