Does your prenatal have iodine?

Even a mild level of iodine deficiency during pregnancy is associated with adverse effects on the resulting child's cognitive development, according to a study in the May issue of The Lancet.

Iodine, linked to the production of thyroid hormones, is known to be essential for a healthy fetal brain and neurological development, and the World Health Organization (WHO) in fact refers to its deficiency as "the single most important preventable cause of brain damage worldwide."

While the WHO warning refers largely to severe deficiency, the new study shows that even mild iodine deficiency in utero is linked to lower IQ and suboptimal reading ability in children

First Trimester Is Key Stage for Adequate Iodine Intake
Based on WHO guidelines on recommended concentrations of iodine during pregnancy, the researchers classified iodine/creatinine ratios of less than 150 µg/g as being iodine deficient and a ratio of 150 µg/g or more as iodine sufficient.

The researchers found women with iodine/creatinine ratios of less than 150 µg/g were more likely to have children with scores in the lowest quartile for verbal IQ, reading accuracy, and reading comprehension, compared with children of mothers with ratios of 150 µg/g or more.

The children's scores worsened when the deficient group (less than 150 µg/g) was further subdivided into 50 to 150 µg/g and less than 50 µg/g.

According to WHO guidelines, pregnant and breast-feeding women are recommended an intake of 250 µg of iodine per day, compared with the recommendation of 150 µg for adults who are not pregnant.