Selenium deficiency can reduce the ability of the body to fight free radicals. As selenomethionine, selenium is part of glutathionine peroxidase that is necessary for detoxification of the body. Selenium is necessary to convert thyroxine T(4) to T(3) and to fight the autoimmune process.
The present study by Duntas, et al, was of patients with autoimmune thyroiditis. For a treatment period of six months, the first group was given 200 mcg selenomethionine plus thyroxine T(4) to maintain thyroid stimulating hormone levels, while the second group was given T(4) plus a placebo in place of selenomethionine.
After the first three months the first groups antibodies against thyroid peroxidase enzyme dropped 46%, and after six months their antibody levels dropped 55.5%. In the second group, which did not receive selenomethionine, the levels dropped only 21% at three months and to 27% at six months. The reduction of antibody levels is taken as a sign of improvement in auto-immune disease. There was a larger drop for the selenomethionine treated group.
CONCLUSION: The authors concluded that selenomethionine is an effective treatment for autoimmune thyroiditis, and selenomethionine was shown to be well absorbed after oral administration. Previous studies have shown that thyroid hormone synthesis was not changed by selenium treatment. Other studies have already shown that selenium treatment improves thyroid patient’s mood and sense of well-being. The exact reason that selenomethionine works is not clear and the authors suggest that further study is needed.