Selenium is a trace mineral that is needed by the body in small amounts to make proteins and enzymes. It also contains antioxidant properties that help to prevent cell damage from oxidative stress and free radicals.
Plant foods are the major sources of selenium because the roots draw the mineral up through the soil. Nuts, such as Brazil nuts, have high levels of the mineral. Selenium can also be found in some meats and seafoods.
Dietary Needs for Selenium
The Dietary Reference Intake (DRI) for selenium for most adults is set at 55 micrograms per day. Pregnancy slightly increases the need for the mineral. Selenium deficiency is rare in healthy, well-nourished people. The National Health and Nutrition Examination Survey found that the diet of most Americans provide the recommended amount.
What Increases the Need for Supplements?
Deficiency can occur as a result of a compromised intestinal function which causes depletion of selenium, such as in the case of those who suffer from Crohn’s disease. Acute illness with widespread inflammation and infection may also increase the need for supplements, as these patients often have decreased blood levels of the mineral.
People who live in places where the crop soil is low in selenium, such as New Zealand, China and Russia, may also have an increased risk for selenium deficiency and a need for nutritional supplements.
Some rare diseases have been associated with selenium deficiency, including Keshan Disease, Kashin-Beck Disease, and Myxedematous Endemic Cretinism. People with iodine deficiency may benefit from selenium supplements, although this condition is rare in the United States.