A recent study concluded that lifelong low selenium levels leads to lower cognitive function. The study was based on rural Chinese where it is possible the soil was selenium depleted. If we eat well we may get adequate levels of selenium, but how do we know we are receiving optimal amounts? And if we take a selenium supplement how do we know that we aren’t getting too much, as selenium is toxic in high amounts? Hmm answer below…
Selenium is a metal that the body uses to make selenoproteins. Selenoproteins are used as antioxidants as well as regulating thyroid function. This is why you hear selenium being talked about as an antioxidant. It isn’t really an antioxidant as it doesn’t donate an electron to reduce a free radical such as vitamin C, E etc. However it is needed for the selenoprotein enzyme, but not an antioxidant per se.
Plant sources of selenium are variable based on where the vegetation was grown. It all depends on how rich the soil is in selenium. Same is true for animal meat, the selenium content depends on the makeup of the soil the animals grazed on or the feed they are given. The best known plant source of selenium is the Brazil nut. Also high are certain mushrooms and garlic. Animal foods higher in selenium are beef, tuna , shellfish, salmon, cod.
But how do we know we are getting enough? Should we supplement? Certainly people with digestive issues such a Crohn’s disease, ulcerative colitis, or other intestinal compromised diseases would benefit from supplementation as well as people with low stomach hydrochloric acid (which can occur if you take Tums for the tummy). My favorite minerals are liquid minerals developed by biochemist Patricia Kane, called E-Lytes. You can use a taste test to determine if you are getting too much selenium as if your stores are adequate you will have an unpleasant taste from the mineral. Plus these minerals are in their ionic form so they are easily absorbed even if one has compromised intestinal absorption.