Endocrine Abstracts

This year marks the 100th anniversary of vitamin D. Since its discovery in 1922 - as a factor that protects against the bone disease rickets - our understanding of vitamin D has evolved dramatically. Vitamin D has morphed from environmental/nutritional factor to steroid hormone endocrine regulator to intracrine modulator of transcription. Despite this, vitamin D-deficiency continues to be prevalent in the UK and nutritional rickets remains a significant clinical problem, notably in ethnic minority groups. For this reason alone, vitamin D supplementation should be a high public health priority. Added to this are the many pre-clinical and observational studies highlighting health benefits of vitamin D beyond rickets. These extraskeletal effects have been less consistent in randomized control trials (RCTs) and Mendelian Randomization (MR) analyses, but both RCTs and MR have limitations that hamper interpretation of the health impact of vitamin D. In particular RCTs are very expensive, frequently involve vitamin D-sufficient cohorts and never target an optimal vitamin D level (we still do not know the level of vitamin D required for key extraskeletal actions). So why not take a pragmatical approach? Assume that a proactive national strategy of vitamin D supplementation will finally eradicate rickets (100 years later than expected) but may also have some broader health benefits across the nation. In a time of increased pressure on our health services this could be a simple and cost-effective strategy. Current UK public health measures have largely failed to tackle vitamin D-deficiency not only because they aim for a low threshold, but also because of inconsistent policies and lack of implementation strategies, leading to confusion for both the general public and healthcare professionals. As we move into the second century of vitamin D, a pro-active programme of vitamin D supplementation, along with food fortification, should be a high public health priority.