Strategies to improve vitamin D status in northern European children: exploring the merits of vitamin D fortification and supplementation.

Adequacy of vitamin D in children in Europe has been the focus of a number of investigations. The results of measuring serum levels of 25-hydroxyvitamin D show high prevalence of vitamin D deficiency during the winter with lower prevalence during the summer. National policies on food fortification or individual supplementation with vitamin D have been recently revisited by the individual countries and the European Union as a whole. Optiford is a project managed by a coalition of scientists formed to optimize vitamin D fortification in the northern European Countries, was given the task to decide if food fortification with vitamin D is feasible and to provide a scientific basis for setting the vitamin D fortification level in Europe. This article presents the results of these investigations to date, with particular attention to potential corrective strategies to allow children and adolescents living in countries at high latitudes to maintain healthy circulating 25-hydroxyvitamin D levels year around, even in the absence of adequate sun exposure during a significant part of the year.