Clinicians across specialties are increasingly aware of health risks associated with vitamin D deficiency (VitD-). The link to bone health is obvious, but there is mounting evidence of associations with disorders including autoimmune and cardiovascular, diabetes, and various cancers (1). Vitamin D is endogenously synthesised in the skin by ultraviolet radiation or orally ingested (2). In the UK, few foods are supplemented with vitamin D, therefore, the main source is sun exposure. Unfortunately, patients in much of the UK are exposed to a UV index <3 for almost half the year, significantly limiting their ability to obtain vitamin D from this modality. This article is protected by copyright. All rights reserved.