TABLE 1.

Calculated UIC cutoffs for sex- and life stage–specific subgroups based on Dietary Reference Intakes for iodine¹

	Dietary Reference Intakes, μg/d			UIC cutoffs, μg/L
	EAR	RDA	UL	EAR-like2	RDA-like3	UL-like4
Children
1–3 y	65	90	200	NC	NC	NC
4–5 y	65	90	300	NC	NC	NC
6–8 y	65	90	300	72	100	300
9–13 y	73	120	600	61	100	300
Teens and adults aged ≥14 y, excluding pregnant females
14–18 y	95	150	900	63	100	300
≥19 y	95	150	1100	63	100	300
Pregnant females
14–18 y	160	220	900	109	150	500
19–50 y	160	220	1100	109	150	500

¹Urinary data were available only for survey participants ≥6 y of age; for that reason, we did not develop UIC cutoffs for children <6 y of age. The EARs, RDAs, and ULs are Dietary Reference Intakes developed by the Food and Nutrition Board of the Institute of Medicine (7). EAR, Estimated Average Requirement; RDA, Recommended Dietary Allowance; NC, not calculated; UIC, urinary iodine concentration; UL, Tolerable Upper Intake Level.

²EAR-like UIC cutoffs were calculated as follows: RDA-like UIC cutoff (μg/L) × EAR (μg/d)/RDA (μg/d).

³RDA-like UIC cutoffs were set at the lowest WHO guideline median UIC cutoffs for adequate iodine intake: 150 μg/L for pregnant females and 100 μg/L for other population subgroups, including lactating females and children ≥6 y of age (1).

⁴UL-like UIC cutoffs were set at the WHO guideline median UIC cutoffs for excessive iodine intake: 500 μg/L for pregnant females and 300 μg/L for other population subgroups, excluding lactating females and including children ≥6 y of age (1).