Dairy food consumption is beneficially linked with iodine status in US children and adults: National Health and Nutrition Examination Surveys 2001-2018

Objectives:The objective of this study was to determine the association between the consumption of dairy foods with urinary iodine concentration (UIC) and iodine deficiency risk in a nationally representative sample of the US population. Design, Setting and Participants:24-hour dietary recall data and laboratory data for UIC (mu g/l) from subjects 2+ years old US population participating in National Health and Nutrition Examination Surveys 2001-2018 were used (n 26 838) for analyses after adjusting for demographic covariates. Significant associations were assessed at P < 0 center dot 05. Results:Mean intakes of total dairy were 2 center dot 21, 2 center dot 17 and 1 center dot 70 cup equivalents (cup eq) among those 2-8, 9-18 and 19+ years, respectively. Of the dairy components, intake of milk was highest followed by cheese and yogurt for all age groups. Total dairy intakes were positively associated with UIC among those 2-8 years (beta = 29 center dot 9 +/- 9 center dot 9 mu g/l urine/cup eq dairy) and 9-18 years (beta = 26 center dot 0 +/- 4 center dot 8 mu g/l urine/cup eq dairy) but not associated among those 19+ years. Total dairy intakes were associated with lowered risks (30 %, 21 % and 20 % for among 2-8, 9-18 and 19+ years, respectively) of being classified as iodine insufficient (UIC < 100 mu g/l) or lowered risk (47 %, 30 % and 26 % among 2-8, 9-18 and 19+ years, respectively) of being classified as iodine severely deficient (UIC < 20 mu g/l). Conclusions:The results indicate that dairy foods are beneficially associated with UIC and lowered iodine deficiency risk.