Abstract Iodine is a trace element that is essential for the synthesis of thyroid hormones in the thyroid gland. Evidence suggests that excess iodine intake exerts a triggering effect on the development of autoimmune thyroiditis (AT), with many studies reporting a rising incidence in iodine sufficient countries. Processing excess iodine in thyroid follicular cells, during thyroid hormone synthesis, may result in increased amounts of reactive oxygen species, leading to thyroid cell damage and the triggering of thyroid autoimmunity. Another trace element, selenium found in high amounts in the thyroid, is very important for thyroid physiology. Selenium is incorporated into selenoproteins...