[Vitamin D: important from before the cradle and to the grave]

Approximately one hundred years ago, vitamin D was recognized as being important for bone health. Nowadays there is increasing evidence that even before birth as well as during lifetime, vitamin D plays a role in the prevention of several chronic diseases as well as cancer. Human beings depend on exposure to the sun to satisfy their daily requirements of vitamin D. Moreover, most doctors in the Netherlands are unaware that the production of vitamin D only takes place in the spring and summertime in the Dutch climate. One Dutch study reports hypovitaminosis D not only in more than half of non-western immigrant mothers and their newborns, but also in 10% of the western mothers and their babies. On a worldwide level, numerous studies report low vitamin-D status in western countries due to our modern way of living, the immigration of dark-skinned people to higher latitudes and the homebound elderly. For some years now the scientific world has called for action on this point; something that in practice appears to be difficult to achieve. Aiming for optimal vitamin-D levels means suppletion either through tablets or food fortification. In general, people do not like to take tablets ('we eat healthy foods already') and many avoid the sun because they are afraid of cancer. Vitamin D is not a commercially rewarding product and has no marketing industry. Although multivitamins are marketed and pushed by industry, they hardly contain the necessary amounts of vitamin D. The population in the Netherlands should be better informed on this issue and general practitioners need more tools in order to play a greater role in informing and advising their patients.