Should individuals with a family history of cancer take selenium supplements? Explain your answer.

Question

What will be an ideal response?

Answer 1

Diets low in fruits and vegetables (rich sources of phytochemicals and antioxidant nutrients, such as selenium, vitamin C, and vitamin E) have been associated with an increased incidence of certain cancers.

Selenium acts as a cofactor for glutathione peroxidase, which prevents the oxidative destruction of cell membranes by hydrogen peroxide and free radicals. Selenium also aids in the conversion of the thyroid hormone T4 to T3. The selenium content of the soil in an area greatly affects the amount of selenium in the foods from that area. In general meat, eggs, seafood, grains, and seeds are the best sources of selenium. In areas where the soil lacks selenium, deficiencies are more prevalent. Selenium deficiency increases the risk of Keshan disease and possibly certain cancers. Because selenium has a narrower range of safety for intake than most other trace minerals, selenium supplementation can cause symptoms of toxicity at lower levels of intake.

However, research evidence does not suggest selenium, alone, PREVENTS cancer. Therefore, in advising an individual about supplements, it is important to understand that selenium supplements alone will not likely prevent cancer. An individual should assess his/her overall diet and determine needs for supplementation if selenium is deficient.