Selenium

Also known as: selenomethionine, selenocysteine.

Potential uses: Selenium may decrease the risk for prostate, colon, gastrointestinal, lung, and breast cancers. Selenium acts as an antioxidant.

Usual dose: 55 micrograms per day. Food sources of selenium include Brazil nuts, seafood, cereals, and grains.

Are there any risks? If you take more than 1,000 micrograms per day, you may have stomach upset, muscle weakness, fatigue, and numbness or tingling in the feet or hands (peripheral neuropathy).

What does the research show? Clinical trials are looking at the possible role of selenium in reducing the risk of breast cancer. One study suggested that selenium may help reduce treatment-related lymphedema. Selenium may reduce hair loss, abdominal pain, and loss of appetite in ovarian cancer patients who are getting chemotherapy.