[Vitamin D deficiency].

The importance of vitamin D for osteoporosis and fractures has been known for more than 40 years. Vitamin D deficiency is diagnosed by measuring 25-hydroxyvitamin D (25-OHD), which should be > 50 nmol/l year round. Recent research suggests that a number of severe diseases could be prevented by increasing 25-OHD to 80 nmol/l. Despite a strong focus on such increase, recommendations for intake of Vitamin D have not been changed and the present recommendations are too low even to ensure > 50 nmol/l. To achieve optimal concentrations > 80 nmol/l, we estimate that 50-70 microgram of vitamin D per day for everyone from the age of 10 years is necessary. Until the safety of this dose has been further documented, we recommend 35-38 micrograms/day.