Comparison of two sources of iodine delivery on breast milk iodine and maternal and infant urinary iodine concentrations in southern Ethiopia: A randomized trial.

Tafere Gebreegziabher,Barbara J Stoecker

doi:10.1002/fsn3.477

Abstract

Iodine deficiency during pregnancy and lactation could expose the infant to severe iodine deficiency disorders. A randomized supplementation trial among rural lactating women was conducted in Sidama zone, southern Ethiopia, to compare the methods of iodine delivery on breast milk iodine, and on maternal and infant urinary iodine concentrations. Women were randomly assigned either to receive 225 μg iodine as potassium iodide capsule daily for 6 months or 450 g of appropriately iodized salt (30–40 μg I as KIO3/g of salt) weekly for household consumption for 6 months. Breast milk iodine concentration (BMIC) and maternal and infant urinary iodine concentration (UIC) were measured at baseline and at 6 months. The women did not differ in BMIC and UIC, and infants did not differ in UIC in a time by treatment interaction. Median (IQR, interquartile range, IQR) BMIC at baseline was 154 [43, 252] μg/L and at 6 months was 105 [36, 198] μg/L, maternal UIC at baseline was 107 [71, 161] μg/L and at 6 months was 130 [80, 208] μg/L; infant UIC at baseline was 218 [108, 356] μg/L and at 6 months was 222 [117, 369] μg/L. Significant correlations among the three variables were obtained in both groups at both times. We conclude that for lactating women an adequate amount of appropriately iodized salt (30–40 μg I/g) had similar effects as a daily supplement of 225 μg I on BMIC and on maternal and infant UIC.

Highlights

Iodine is required for the synthesis of thyroid hormones; thyroid hormones in turn regulate the metabolic patterns of cells
This study showed Breast milk iodine concentration (BMIC), maternal urinary iodine concentration (UIC) and infant UIC were not significantly different between mothers who received 225 μg of iodine daily as a capsule for 6 months in addition to variable amounts of iodine in their existing household salt and mothers who received 450 g per household of appropriately iodized salt (30–40 μg/g) delivered weekly for 6 months
The median infant UIC at baseline was significantly higher than BMIC (p < .001) and maternal UIC (p < .001) and, not significant, median BMIC tended to be higher than maternal UIC

Summary

| INTRODUCTION

Iodine is required for the synthesis of thyroid hormones; thyroid hormones in turn regulate the metabolic patterns of cells. The Institute of Medicine (IOM) in the USA set the adequate iodine intake for infants 0–6 months of age at 110 μg/ day This recommendation is based on two important points. Double- blind, placebo-c ontrolled study, supplementation to lactating women of either 75 μg/day or 150 μg/day of iodine as potassium iodate for 6 months significantly increased the BMIC and maternal urinary iodine concentration (UIC). Our study with lactating women compared the efficacy of appropriately iodized household salt to daily intake of iodine capsules in raising the BMIC and maternal and infant UIC in a context of villagers already having some access to iodized salt

| MATERIALS AND METHODS

Findings

| DISCUSSION

CONCLUSIONS