[decimon]

But don’t go overboard and take too much selenium.

I take a vitamin-mineral-whatever pill each day as a supplement. Just a supplement. I take additional vitamin D.

[aruanan]

You're not necessarily safe just sticking to a multi-vitamin. This happened in 2008:

Toxic Levels of Selenium in Dietary Supplements.

You can look here for toxicology facts about selenium.

As with most micronutrients, not having enough will harm you and having too much will harm you. The typical amount that is set for the RDA is more than enough to prevent the classic deficiency disease for that micronutrient. The maximum dosage is still far short, for most of them, of an amount that could cause harm, though it varies depending on the type of vitamin or mineral. The fat soluble vitamins, especially D and A, can reach toxic levels much more quickly than the water soluble vitamins, especially vitamin C, because their half-life in the body is so much longer. I'll try to find my RDA book when I get home. It seems I saw it somewhere not too long ago. It has all the specifics about each of the vitamins and minerals and how the RDAs for them were determined.