Some thyroid conditions are caused by the immune system mistakenly attacking the thyroid gland. These are known as autoimmune thyroid diseases. Testing for thyroid antibodies can provide additional information when thyroid disease is suspected, particularly if thyroid hormone levels are abnormal or symptoms continue despite normal routine thyroid testing.

Thyroid Peroxidase (TPO) Antibodies

A thyroid peroxidase (TPO) antibody test measures antibodies directed against thyroid peroxidase, an enzyme involved in making thyroid hormones. Elevated TPO antibodies are commonly associated with Hashimoto's thyroiditis, the most common cause of underactive thyroid (hypothyroidism).

Graves' disease is another autoimmune thyroid condition. Unlike Hashimoto's thyroiditis, Graves' disease most often causes the thyroid to become overactive (hyperthyroidism).

Thyroid disorders, such as hypothyroidism and Hashimoto’s, may make it difficult for your body to get the nutrients it needs. Measure the levels of 5 nutrients in your blood that research has shown can be affected by thyroid disorders. The Thyroid Disorder Nutrient Deficiency Panel measures the levels of the following 5 nutrients in your blood: vitamin D, iodine, ferritin, iron, and selenium. Shop more nutrient tests below.