Iodine deficiency on the rise globally: Must focus on natal nutrition, study warns

12 Mar 2018 --- Iodine is an essential nutrient particularly for the neurodevelopment of fetuses. Deficiency at this stage could have negative consequences, a review conducted by the Hospital de Riotinto, Spain and Unversity of Surrey, UK, have shown. The findings are of rising importance as iodine deficiencies are becoming more common, the review suggests.

The review was conducted as a response to growing concerns over substantial levels of iodine deficiencies in industrialized countries. Beforehand, it was largely assumed that iodine deficiencies were only prevalent in certain geographic areas and with particular groups, such as malnourished people.

Iodine is a key nutrient required for the formation of the thyroid hormones. Iodine deficiency - a preventable cause of brain damage and impaired development - remains a challenge to lifelong health globally.

The objective of the joint review was to summarize the available evidence from both animal and human studies for the effect of iodine deficiency. The review was particularly in regards to maternal hypothyroxinemia's (which is a subnormal thyroxine concentration in the blood) effect on brain development and neurological or behavioral disorders, such as lower intelligence quotient (IQ) or attention deficit hyperactivity disorder (ADHD).

Key findings
Pregnancy involves a higher demand for thyroid hormones, which may not be adequately met even in healthy pregnant women living in areas where the deficiency is relatively uncommon. 

The findings showed that fetal neurodevelopment is not only affected when the mother is hypothyroid but also when she is “hypothyroxinemic” in the early stages of pregnancy and studies have demonstrated the existence of maternal hypothyroxinemia even in iodine sufficient areas.

Significantly, if transfers of the thyroid hormone from mother to baby are compromised, it can lead to permanent lesions of the cerebral cortex, hippocampus and cerebellum. This can result in post-natal behavioral disorders such as ADHD or autism.

NutritionInsight has previously reported on calls for food items to be fortified with beneficial pregnancy nutrients, such as folic acid. This research is a loud call for more iodine supplementation during pregnancy for all mothers: globally. And importantly, it is a wakeup call to iodine deficiency’s growing presence in industrialized countries.