As an essential cofactor of glutathione peroxidase,86 selenium is an important antioxidant.87 Selenium is incor-porated into proteins to make selenoproteins, which are important antioxidant enzymes. The antioxidant properties of selenoproteins help prevent cellular damage from free radicals. Other selenoproteins help regulate thyroid function and play a role in the immune system, DNA repair, and the detoxification of heavy metals.87-92* High doses of vitamin C (over one gram) may reduce the absorption of selenium. This mineral is best taken one hour before or 20 minutes after taking vitamin C supplements.93

Sodium selenite liquid provides a convenient way of supplementing the diet with more selenium.