NCIt definition : A nonmetallic chemical element found in trace amounts in human body. Selenium primarily
occurs in vivo as selenocompounds, mostly selenoproteins such as glutathione peroxidase
and thioredoxin reductase (enzymes responsible for detoxification). Alone or in combination
with Vitamin E, selenocompounds act as antioxidants. These agents scavenge free radicals;
prevent blood clots by inhibiting platelet aggregation; strengthen the immune system;
and have been shown, in some instances, to inhibit chromosomal damage and mutations.
Exhibiting chemopreventive activity, selenocompounds also inhibit the induction of
protein kinase C.;
Alternative definition : NCI-GLOSS: A mineral that is needed by the body to stay healthy. It is being studied
in the prevention and treatment of some types of cancer. Selenium is a type of antioxidant.;