Urinary iodine concentration: United States National Health And Nutrition Examination Survey 2001-2002.

Urine iodine has been measured in the U.S. population by the National Health and Nutrition Examination Survey (NHANES) since 1971. A downward trend was noted between NHANES I (320 +/- 6 microg/L in 1971-1974) and NHANES III (145 +/- 3 microg/L in 1988-1994). This report presents data from NHANES 2001-2002 that indicates that the U.S. median urine iodine (UI) level has stabilized since the initial drop between NHANES I and NHANES III. The median UI concentration in the U.S. population in NHANES 2001-2002 was found to be 167.8 microg/L (95% confidence interval [CI] 159.3-177.6). The NHANES 2001-2002 data confirm the current stability of the U.S. iodine intake and continued adequate iodine nutrition for the country.