Supplements for Hashimoto’s Thyroiditis

A 2024 meta-analysis published in Frontiers in Endocrinology compared the effectiveness of several dietary supplements in supporting patients with Hashimoto’s thyroiditis, an autoimmune disorder in which the immune system mistakenly attacks the thyroid gland. Researchers reviewed data from 10 studies drawn from international databases to assess how well each supplement lowered thyroid autoantibodies, which are are the immune system proteins that attack the thyroid; the presence of these autoantibodies is a key indicator for autoimmune conditions like Graves disease and Hashimoto's thyroiditis.

The primary supplements were selenium, vitamin D, and Myo-inositol. Among the supplements tested, selenium showed the clearest benefit. Compared to placebo, selenium significantly reduced the two types of antibodies that indicate ongoing thyroid inflammation. In contrast, vitamin D, myo-inositol, and their combinations did not show consistent effects in lowering these antibody levels over six months of treatment.

Selenium is a trace mineral that supports the immune system, thyroid function, and brain health. Its importance in Hashimoto's thyroiditis treatment stems from its role in thyroid hormone metabolism and antioxidant protection, helping convert prohormone thyroxine (T4) into its active form, triiodothyronine (T3). The thyroid naturally contains more selenium than any other organ, and a deficiency can impair hormone conversion and promote inflammation. While adequate selenium may help regulate immune responses and protect thyroid cells, excessive intake can be toxic, so supplementation should be carefully monitored.

Vitamin D, which supports immune balance and bone health, has also been linked to thyroid health in some studies, though results remain mixed. Myo-inositol, a natural compound involved in cell signaling, may enhance thyroid function when paired with selenium, but evidence is still emerging.