Iodine: the essential nutrient for your baby's brain and your thyroid

It is essential for the synthesis of thyroid hormones, T3 and T4, which play a central role in regulating metabolism, growth, and neurological development — in both mother and baby.

Its importance is particularly critical during pregnancy and breastfeeding — two periods when needs increase significantly and where prolonged deficiency can have lasting consequences on the child's cognitive and psychomotor development. The form of iodine used, whether potassium iodide or organic iodine derived from seaweed, directly determines bioavailability and digestive tolerance.

In its natural form, Iodine-rich foods include seafood: sea fish, shellfish, crustaceans, and sea vegetables such as kombu, dulse, and nori. Dairy products — particularly milk and yoghurt — are also a significant source in Western diets, as cows are often given iodine-supplemented feed. Eggs and certain breads made with iodised salt also provide modest amounts. The absorption of dietary iodine depends on the chemical form in which it is found, the food matrix, and the presence of goitrogens — substances found in certain cruciferous vegetables that can interfere with its absorption when consumed in very large quantities. Achieving adequate intake through diet alone can be difficult to guarantee, particularly for women who do not eat seafood regularly or who follow a vegan diet.

In the form of supplements, iodine is found primarily in potassium iodide, a highly absorbable mineral form used in multivitamins and pregnancy supplements, and organic iodine derived from standardised sea vegetables. Potassium iodide is the reference form in a pregnancy vitamin, as its bioavailability is excellent and its content can be precisely controlled from one batch to the next. Sea vegetables, such as the royal kombu used in the Jolly Mama granolas, provide a natural iodine integrated within a complete food matrix, making them a valuable complementary source. It is important to verify the traceability of the seaweed used, its origin, and its testing for heavy metals — all essential quality criteria. People with thyroid conditions must seek medical advice before taking any iodine supplement.