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Geographical differences in vitamin D status, with particular reference to European countries

Published online by Cambridge University Press:  07 March 2007

Rikke Andersen
Affiliation:
Institute of Food Safety and Nutrition, The Danish Veterinary and Food Administration, 30A Sydmarken, 2860 Søborg, Denmark
Jette Jakobsen
Affiliation:
Institute of Food Safety and Nutrition, The Danish Veterinary and Food Administration, 30A Sydmarken, 2860 Søborg, Denmark
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Abstract

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Vitamin D is produced endogenously when the skin is exposed to sunlight and can be obtained exogenously from a few natural food sources, from food fortification and from supplements. Generally, vitamin D intake is low ≤2–3 μg/d in Europe. Casual exposure to sunlight is thought to provide most of the vitamin D requirement of the human population. However, skin synthesis of vitamin D may not compensate for the low nutritional intake in Europe, even in countries with high supplies from food fortification and supplements. For assessment of vitamin D nutritional status the concentration of 25-hydroxyvitamin D (25(OH)D) in serum is considered to be an accurate integrative measure reflecting an individual's dietary intake and cutaneous production. A substantial percentage of the elderly and adolescents in Europe have a low concentration of 25(OH)D; in the elderly this percentage ranges from approximately 10 in the Nordic countries to approximately 40 in France. Low vitamin D status seems to be aggravated by disease and immobility, and by a low frequency of supplement use.

Type
Symposium on ‘Optimal nutrition for osteoporosis prevention’
Copyright
Copyright © The Nutrition Society 2003

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