What is selenium?
The nutrient selenium is a so-called trace element. The word "trace" refers to the fact that it is needed in small (trace) amounts for maintenance of health and normal functioning of the human body. Selenium is an inherent part of numerous selenium-dependent molecules, enzymes and selenoproteins that support metabolic functions, human reproduction, immune defence mechanisms, brain functions and cardiovascular health. Selenium is also linked to defence mechanisms of importance to the body's ability to ward off cancer.

Selenium's different forms
Selenium occurs in various organic and inorganic forms. Plants absorb inorganic selenium from the soil, converting it into organic selenium by incorporation in amino-acids (methionine, cystine and cysteine) which is more readily available to animals and humans. The organic form of selenium is embedded in the different selenium-dependent proteins and molecules and is therefore superior to inorganic selenium for supplement use.

Since the 1980's, various organic selenium sources have been used in vitamin pills and selenium-containing antioxidant supplements. Even among the organic species there are quality differences that determine the biological activity of the nutrient. For years, pure l-selenomethionine, a particularly active, but synthetic, form of organic selenium, was the preferred choice for high-quality supplements, but with the introduction of SelenoPrecise®, a whole new standard has been set for selenium.