Vitamin D status of Inuit preschoolers reflects season and vitamin D intake

Abstract

Rickets ascribed to hypovitaminosis D remains a public health concern among Aboriginal children in Canada and the United States. Our primary objective in this study was to investigate the prevalence and risk factors (gender, age, vitamin D intake, and socioeconomic status) for low vitamin D status of Inuit preschoolers living in 16 Arctic communities (51°N-70°N) and participating in the 2007-2008 Nunavut Child Inuit Health Survey. Children were selected randomly in summer (n = 282) and a follow-up was performed in winter for a subsample (n = 52). Dietary intake was assessed through the administration of a 24-h dietary recall and a FFQ. Anthropometric measurements (height, weight) were assessed. Plasma 25-hydroxy vitamin D was measured using a chemiluminescent assay (Liaison, Diasorin). Prevalence of vitamin D insufficiency (<75 nmol/L) among preschoolers was 78.6% and 96.8% in summer and winter, respectively. Median vitamin D concentrations and interquartile ranges in summer and winter were 48.3 (32.8-71.3) and 37.7 (21.4-52.0) nmol/L, respectively. The prevalence of vitamin D deficiency < 25 and < 37.5 nmol/L was 13.6 and 36.5%, respectively. Children who met or exceeded the adequate intake, those who consumed 2 or more milk servings (1 serving = 250 mL), and those who lived in households without crowding (47.7%) had a better vitamin D status than those who did not. The predictors of vitamin D status were dietary intake and age. Given low traditional food consumption and low consumption of milk, interventions promoting vitamin D supplementation may be required. © 2010 American Society for Nutrition.