D Doh!

A large meta-analysis has suggested that taking vitamin D supplements in the winter months (when most people in the UK would produce less of this material as a consequence of reduced UV radiation of the skin) has no benefit on bone health (https://www.theguardian.com/society/2018/oct/04/vitamin-d-supplements-dont-help-bone-health-major-study-concludes). The authors consequently suggest that government advice to take supplements be rescinded. I am somewhat ambivalent about this as a) Dietary advice clearly ought to be evidence led but b) Dramatic volte-faces in such advice cast doubt on any recommendations. Perhaps the initial advice was premature (before the available data had been properly evaluated) or fluctuating advice has been driven by competing interest groups?