At the cellular level, selenium is an active component of glutathione peroxidase, which has potent antioxidant properties and serves as a first line of defense against build-up of harmful free radicals in your cells
By reducing free radicals, selenium also helps reduce your risk of cancer. Studies show higher selenium levels can cut your risk of prostate cancer by as much as 63 percent, and lung and colon cancer by about 50 percent
For cancer prevention, the recommended dosage is 200 mcg of SelenoExcell® high selenium yeast per day. Avoid exceeding 400 mcg per day as toxicity may be an issue