I've noticed that a lot of members are recommending selenium haphazardly. While it's true that selenium can possibly help, too much selenium can be very toxic.
Common signs of toxicity are hair loss, nail discolouration. Selenium treatment NEEDS to be done along side labs and with the help of a qualified doctor. I did 2 months of selenium treatment myself and ended up with a result of 194mcg/l (safe range is 50-150). And my Endo told me I had to immediately stop before it gets dangerous, this is in just 2 months of taking a low dose (200mcg). On top of that my antibodies actually doubled and my TSH went up and FT4 went down. So it's not just an easy, magical solution for everyone, it can actually be quite detrimental.
Guys if you're going to recommend selenium as a treatment please make sure the other person knows of the dangers, and that they need to be regularly tested for toxicity.