Hi Hip, an interesting discussion. I find that daily selenium and vitamin C taken together have a beneficial effect, but are not curative. I had mito testing with Dr Myhill and she found i had a very messed up antioxidant system with a blockage on the MnSODase gene. But it seems that no amount of antioxidants really budges my symptoms that much, and i wonder why my system is so messed up in the first place. I was under the impression, and have read extensively on selenium, that the safe upper limit is 400mcg a day. Dr Myhill recommends 200mcg a day for a safe maintenance dose, but 400mcg a day for those with deficiencies, but for a few months only. I take this advice to heart as she is not normally overly cautious with dosing and prefers her patients to rectify problem with the highest possible dose of most supplements. I notice people on this thread bandying around very high doses and also someone sayine we all try supplements, they cant do any harm. Let me remind everyone reading this thread that selenium toxicity can be fatal. It can build up in the body and cause death. I'm not saying people shouldnt take it - i wish i could safely take more. But we need to be aware that we are not discussing some slight unpleasant side effect here. All the best, Justy @Hip sorry to point out that some of your sources are from Wikipedia, which is not a reliable source.