Information Types of thyroid disorders Iodine and thyroid Iodine is an element that plays an essential role in the functioning of a healthy thyroid. It is used for the production of thyroid hormones. It is particularly important in women who are pregnant as it is needed to ensure the development of a baby's brain during pregnancy and early life. Adults need 150mcg of iodine per day. Iodine and hypothyroidism If you have hypothyroidism (underactive thyroid) and are taking levothyroxine you do not have a functioning thyroid to absorb iodine and therefore you do not require iodine. Iodine and hyperthyroidism If you are being treated for hyperthyroidism (overactive thyroid), taking an iodine supplement is unnecessary and can worsen the condition. For further information about the importance of dietary iodine please see the following resources: Iodine Facts by the British Dietary Association (BDA) UK Iodine FAQs about iodine in the diet, questions relating to iodine and thyroid disorders and importance of iodine in pregnancy. UK Iodine advice about iodine supplements UK Iodine Group The BBC Radio 4 series 'In their Element' featured a programme about 'Awesome iodine'