some minerals are retained in the body more than others. excretion rates vary. Iodine is very forgiving in that respect, being out of serum in 24 hours.
of course we all know it is way more complicated than that, but Iodine is profound in its effects but fairly benign as to any long term conditions or damage that might result. i am convinced additional selenium is more important than ever, though i sis not take any except in the form of brazil nuts for the first year i iosupped.