After categorizing different types of ATID, studies revealed that a dose of 200 μg selenium intake (selenomethionine) once per day was effective in reducing anti-thyroid peroxidase antibody (TPOAb) levels and improving well-being and/or mood in patients with Hashimoto’s thyroiditis compared to a placebo after 3 months (26). This evidence concerns the gene TPO and Hashimoto thyroiditis.