Iodine deficiency has a substantial impact on mental development in children 5 years old and under

Objectives:
Several reviews and meta-analyses have examined the effects of iodine on mental development. However, none focused on young children, so they were incomplete in summarizing the effects on this important age group. Therefore, this review article has been conducted.

Is there a relationship between iodine and mental development of children 5 years old and under?

Study design:
This review article included 24 studies (14 cohort en 10 intervention studies).
Studies providing supplementation to women before or during pregnancy tended to give injections of iodized oil of 950 mg; only the studies conducted in China and DR Congo gave lower doses (400 and 475 mg, respectively).
The median sample size per group across the 10 intervention studies was 50 with a range of 7 to 624.

Results and conclusions:
The investigators found that the best estimate to date of the effect size of iodine supplementation on mental development in children 5 years old and under was 0.49, which translated into 7.4 IQ points lost due to iodine deficiency.

The investigators found 6.9 to 10.2 IQ points lower in iodine deficient children compared with iodine replete children.

The investigators concluded, regardless of study design, iodine deficiency has a substantial impact on mental development in children 5 years old and under. To further quantify the importance of iodine for mental development in young children, this review points to the need for well-designed randomized controlled trials with adequate sample sizes as well as studies that assess the effectiveness of iodized salt.

Original title:
Iodine and Mental Development of Children 5 Years Old and Under: A Systematic Review and Meta-Analysis by Bougma K, Aboud FE, […], Marquis GS.

Link:
http://www.mdpi.com/2072-6643/5/4/1384/htm

Additional information of El Mondo:
Find more information/studies on iodine right here.