Vitamin D has recently attracted a considerable amount of media attention. This article investigates whether the notion of a widespread vitamin D deficiency is justified in the UK, and what effect it might have on the general populace. Also considered are which physiological systems vitamin D affects in addition to bone remodelling, as well as the latest findings as to how this vitamin can benefit the body. Reasers are also given information as to which medications might adversely affect vitamin absorption, which patient groups are most at risk of deficiency, and the most practical and cost-effective means to treat patients suffering from a lack of vitamin D.