Selenium 100 mcg

What Is Selenium?

Selenium is a trace mineral that plants draw out of the soil, so the amount in a food tracks the ground it grew in. Brazil nuts, seafood and organ meats are the dense sources. Here it comes as L-selenomethionine, the form found in food: the amino acid methionine with selenium sitting where its sulfur would.

How It Works in the Body

Selenium's job is to become part of proteins. The body builds it into selenocysteine, a twenty-first amino acid slotted into roughly twenty-five human proteins. Those selenoproteins include the glutathione peroxidases, which quench peroxides before they reach membranes, and thioredoxin reductase, which keeps the cell's redox chemistry turning over. A third group activates thyroid hormone by clipping one iodine atom off it.

What It Supports

• Antioxidant defense: Selenium is built into the glutathione peroxidases, the enzymes that handle peroxides.
• Thyroid function: Selenium supports normal thyroid function, since the enzymes that activate thyroid hormone are selenoproteins.
• Immune function: Selenium supports normal immune function; immune cells carry selenoproteins in quantity.
• Male fertility: A selenoprotein forms the structural sheath around the midpiece of a sperm cell.

Who It May Suit

Selenium in food follows the soil, so regional intake varies widely. It suits adults who eat little seafood and few Brazil nuts. The tablet contains no animal ingredients, so it fits vegetarian eating.

Good To Know

L-selenomethionine slots into body protein in place of methionine, which builds a selenium reserve the body can draw on; inorganic forms such as sodium selenite do not. Selenium has a narrow range between adequate and too much, with a defined upper limit for adults. Talk with your healthcare provider before use if you already take a multivitamin containing selenium or eat Brazil nuts often.