Understanding Prenatal Iodine Deficiency

Abstract

Iodine is a micronutrient essential for the synthesis of thyroid hormones1. The thyroid gland takes iodine from the diet, stores it and subsequently incorporates it into other molecules, to produce two types of thyroid hormones as a final product: triiodothyronine (T3) and thyroxine (T4) containing three and four iodine atoms respectively. Both circulate in blood bound to proteins and act on specific receptors. The free T3 is metabolically more active, but the T4 is, as we shall see, indispensable at specific developmental stages.