Vitamine D

Severe vitamin D deficiency can cause rickets in children and osteomalacia, osteoporosis and fractures in adults.

Vitamin D deficiency (25-hydroxyvitamin D < 50 nmol/l in elderly, < 30 nmol/l in children and adults) is common in risk groups such as young children and elderly.

The standardized measurement of 25-hydroxyvitamin D has been improved through use of mass spectrometry.

Vitamin D deficiency is associated with numerous extraskeletal disorders, but evidence for causality is often lacking. In cases of deficiency, vitamin D supplements appear to decrease the incidence of acute respiratory infections and exacerbations of asthma and COPD.

Prevention of vitamin D deficiency is possible with sun exposure, nutrition, fortification of foods and use of supplements.

Vitamin D supplementation is desirable in risk groups such as young children, pregnant women, frail elderly and non-western immigrants. A loading dose is not recommended.

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