Pregnant women and mothers breast-feeding their babies are being advised by the Government to boost their intake of vitamin D in the winter to prevent their child suffering rickets or seizures. The vitamin deficiency was thought to have been eradicated in Britain in the 1950s. But many cases of rickets are being found now in Asian, Afro-Caribbean and Middle Eastern children with some research suggesting it could be as high as one in 100 children in ethnic minority groups.