Iodine nutritional status of pregnant Brazilian women according to biochemical and dietary markers: EMDI-Brasil study.

Abstract

The scope of this study was to characterize the iodine nutritional status of pregnant Brazilian women according to biochemical and dietary markers. It involved a cross-sectional study of 2,376 pregnant women. A semi-structured questionnaire was used to characterize the population. Urine samples were collected to investigate iodine nutritional status, and a 24-hour recall was used to assess food consumption. For the statistical analysis, the Shapiro-Wilk test was applied to verify the normality pattern, and descriptive analyses were conducted. The median urinary iodine concentration (UIC) was 186.6 µg/L. There was a 36.7% prevalence of iodine deficiency, 28.7% of iodine excess and 3.6% of iodine deficiency. The median iodine concentration was 26.6 mg/kg in salt, 1.1 mg/100 g in seasonings, 2.9 µg/L in water and 19.4 µg/100 g in fresh food. The average iodine intake was 160.2 µg. When assessing dietary intake, 49.8% of the pregnant women had a habitual iodine intake below 160 µg and none had an excessive intake. The conclusion drawn is that the median UIC showed adequate iodine nutritional status, though a high prevalence of iodine deficiency and excess was observed. In addition, iodine nutritional status varied, which may reflect socioeconomic and health inequalities.