I meant to respond sooner to say that I caught the bit about taking 400 mcg selenium plus eating brazil nuts. It is possible to get too much of a good thing. It takes about 3 years for your body to reach a steady state with regard to selenium. But you can overdo it in your daily intake in the meantime. IMO, you're okay on the 400 mcg maybe even for a year -- it depends on how much selenium you had stored to begin with. But after that, go down to 200 mcg and let your body take its time. Take it day after day, month after month, instead of splurging now, and then dropping it when something else comes along. Boring, I know. That would mean dropping the brazil nuts, from which you can never know exactly how much selenium you're getting. Just my opinion, of course :)