Ok, I have just pulled my foot out of my mouth.
Selenium is not a heavy metal. 200 mcg is recommended to reduce antibody counts. I have not seen any studies that suggest it will lower antibodies more than 10-15%.
Selenium is available in a wide variety of foods, as well as in the form of a supplement. Here is an interesting link. I have no idea if it is reliable or not.
http://dietary-supplements.info.nih.gov/factsheets/selenium.asp
However, I was wrong. 898 is correct.
200 micrograms of a HEAVY METAL could also make you very ill. It is not recognized by the mainstream medical community to be of any real value.
Unless you monitor the build up of selenium in your body, you could end up poisoning yourself.
High TSH and TPO suggesting the autoimmune thyroid disease (Hashimoto thyroiditis)
The good endo must monitor the TSH levels; most hypothyroid patients feeling better as TSH is around 1.0. The 200 microgram dose of selenium supplement is believed to reduce the TPO level (which should slow down the progression of disease), according to the recent study.
You may have to see the endo, but the GOOD one.