Rickets is a childhood bone disease caused by severe vitamin D deficiency. It causes bone pain, weak bones and bone deformities in growing children. In the 1920s the link between rickets and vitamin D was discovered and within a couple of decades rickets largely disappeared from the developed world. Until now. A flurry of articles in the media this week (links below) reports a resurgence of rickets in England, Scotland and Ireland. One hospital in Southampton is reported to have treated 40 chi...