There has been concern raised about a resurgence of vitamin D deficiency and rickets among infants and children, with reports emerging in the United States from Alaska, 1,2 Iowa, 3 Nevada, 4 California, 5 North Carolina, 6 Texas, 7 and mother - infant pairs in Boston, 8 among others.9 The prevalence of vitamin D deficiency in young children also appears to be high in other countries,
including England, 10 Greece, 11 and Canada.12, 13 One study from China
found a 65.3 % prevalence of vitamin D deficiency among 12 - to 24 - month - olds, but few cases (3.7 %) of
radiographic or clinical rickets were noted.14 Previous studies suggest risk factors to be dark skin pigmentation1,3 - 12 and breastfeeding without supplementation.1 - 7, 9,12,13 To date, reports have focused primarily on young infants compared with toddlers.