Iodine Status of the U.S. Population, National Health and Nutrition Examination Survey, 2005–2006 and 2007–2008

Abstract

Background: This report presents urinary iodine (UI) concentrations for the general U.S. population during 2005–2006 and 2007–2008. These findings are the fourth and fifth assessments of the population since National Health and Nutrition Examination Survey (NHANES) III (1988–1994), when the median UI concentration for the population decreased from NHANES I (1971–1974). Methods: During 2005–2006 and 2007–2008, ∼5000 participants per year were selected to participate in NHANES. The participants were interviewed and examined. UI concentration was measured on a random one third subsample of 2649 participants, aged 6 years and older in 2005–2006, and in all participants in 2007–2008. These urine iodine concentrations are representative of the general U.S. population by age, sex, and race/ethnicity. Results: (i) The median UI concentrations for the general U.S. population in 2005–2006 and 2007–2008 were 164 μg/L (95% confidence interval [CI] 154–174) and 164 μg/L (95% CI 154–173), respectively. Also, the proportions of the population with a UI concentration of Conclusions: These findings affirm the stabilization of UI concentration and adequate iodine nutrition in the general U.S. population since 2000. However, certain groups likely do not achieve a sufficient dietary iodine intake according to the World Health Organization. The needs of these vulnerable groups and the inadequacy of their dietary iodine intake should be addressed in future efforts.