In Part 1 in this series on Thyroid and Iodine, Dr. Ruscio delves into the immense body of research available today on the topic. He goes into depth on what the research tells us on thyroid, hyposthyroidism and thyroid autoimmunity, why halogens might not be that important, and the importance of the Sodium/Iodide Symporter and the recommended lab tests for thyroid health and iodine sufficiency.