To estimate adequacy of iodine intake among women of reproductive age (WRA) at national and sub-national (six geographical zones stratified by rural and urban areas) in India.
A national and sub-national representative multistage survey was undertaken with 42 clusters in each of the 12 strata. Twelve households were selected from each selected cluster. Survey tools included a household and a WRA questionnaire. Spot urine samples, to measure iodine, were collected from all consenting WRA from every alternate household.
An optimal median urinary iodine concentration (MUIC) of 158 µg/L was found among WRA at the national level. The MUIC varied however across rural (148.5 µg/L) and urban (167.9 µg/L) areas. The Central zone reported the lowest MUIC (128.6 µg/L) and the North zone reported the highest (204.0 µg/L). The MUIC varied by category of the woman’s household salt iodine content; 112.4 µg/L for non-iodised salt, 123.4 µg/L for inadequately iodised salt and 168.4 µg/L for adequately iodised salt. Women from more deprived households (based on the Multidimensional Poverty Index score) had lower MUIC (144.0 µg/L) as compared to non-deprived household (162.6 µg/L).The national MUIC amongst pregnant women was 124 µg/l (however only 148 pregnant women were included in the survey).
This first report of optimal iodine status amongst WRA in India masks significant differentials at sub-national level. The strategy for elimination of iodine deficiency should develop interventions around observed sub-national differentials to ensure sustained optimal iodine status across all population groups.