Selenium is a naturally occurring mineral which has been shown:

(a) to be higher in the soils of geographical locations in the U.S. with low overall cancer incidence

(b) to be higher in the soil of countries of the world with low cancer incidence

(c) to be lower in patients with a higher risk of developing cancer over time

(d) to be higher in cancer patients who live a long time after the diagnosis of cancer

(e) to stimulate a heightened immune reaction in animals in a variety of experimental settings

(f) to induce a person or an animal to increase endogenous production of glutathione peroxidase, a powerful, naturally occurring, antioxidant enzyme