s thyroiditis is a progressive disease where the thyroid
antibodies begin to destroy natural thyroid
gland protein cells. Those with very high elevations of thyroid antibodies may see faster cell destruction and damage to the thyroid gland. Selenium has been shown to lower TPO antibodies in clinical trials so you might also see an improvement in TPO antibody levels.
Labs for hypothyroidism include: TSH, free T4, free T3, thyroid antibodies - TPOAb, TgAb, reverse T3.