I'd read Roby Mitchell M.D.'s web site as he is DrFitt and he recommends Iodoral which is an iodine and potassium supplement. He has lots of vlogs on YouTube and he has a practice in Texas. He went to medical school at Texas Tex and he also has a PhD, as he studied in China. He is a very interesting man. I found him since my son had Testicular Cancer and had to have surgery and 4 rounds of Chemotherapy. Dr. Mitchell has had Advanced Prostrate Cancer and he cured himself with diet and exercise. He writes a lot about thyroid.