Addition of microencapsulated iron to iodized salt improves the efficacy of iodine in goitrous, iron-deficient children: a randomized, double-blind, controlled trial.

OBJECTIVE: In many developing countries, children are at high risk for both goiter and anemia. Iron (Fe) deficiency adversely effects thyroid metabolism and reduces efficacy of iodine prophylaxis in areas of endemic goiter. The study aim was to determine if co-fortification of iodized salt with Fe would improve efficacy of the iodine in goitrous children with a high prevalence of anemia. DESIGN AND METHODS: In a 9-month, randomized, double-blind trial, 6-15 year-old children (n=377) were given iodized salt (25 microg iodine/g salt) or dual-fortified salt with iodine (25 microg iodine/g salt) and Fe (1 mg Fe/g salt, as ferrous sulfate microencapsulated with partially hydrogenated vegetable oil). RESULTS: In the dual-fortified salt group, hemoglobin and Fe status improved significantly compared with the iodized salt group (P<0.05). At 40 weeks, the mean decrease in thyroid volume measured by ultrasound in the dual-fortified salt group (-38%) was twice that of the iodized salt group (-18%) (P<0.01). Compared with the iodized salt group, serum thyroxine was significantly increased (P<0.05) and the prevalence of hypothyroidism and goiter decreased (P<0.01) in the dual-fortified salt group. CONCLUSION: Addition of encapsulated Fe to iodized salt improves the efficacy of iodine in goitrous children with a high prevalence of anemia.