Objective  To investigate dietary iodine intake, iodine sources and their contribution rates among adult women in regions with high and appropriate drinking water iodine for providing evidences to develop the guidance on healthy diet for residents in China.

  Methods  Information on daily diet, drinking water, table salt intake were collected with the Food Frequency Questionnaire among 1 320 women aged 18 – 60 years in regions with high and appropriate drinking water iodine in two provinces of China duing July – August 2018. Iodine content in food, drinking water and table salt were measured simultaneously and average daily iodine intake was estimated for the women. Iodine intake-related potential risks for the women were assessed according to the national dietary iodine intake recommendations.

  Results  The daily dietary iodine intake was 441.52 μg and 180.67 μg for the women in the regions with high and appropriate drinking water iodine and the intakes were between the reference nutrient intake (RNI) and tolerable upper intake level (UL). Of the women in the regions with high drinking water iodine, 18.12% had the iodine intake higher than UL and 27.14% had the intake lower than RNI. For the women in in regions with high and appropriate drinking water iodine, the edible rate of iodized salt was 8.96% and 25.93%; the contribution rate of iodized intake salt to daily iodine intake was 0.03% and 8.39%; the daily intake of drinking water iodine was 383.06 μg and 93.06 μg; and the contribution rate of drinking water iodine to daily iodine intake was 84.22% and 53.71%, respectively.

  Conclusion  The iodine intake is appropriate and safe and drriking water iodine is the main source of dietary iodine for the adult women in regions with high and appropriate drinking water iodine. Low edible rate of iodized salt may lead to a risk of iodine deficiency for the adult women in regions with appropriate drinking water iodine.