Selenium: An essential mineral that is a component of an antioxidant enzyme, glutathione reductase, that is key in tissue respiration. Food sources of selenium include seafoods; some meats, such as kidney and liver; and some grains and seeds. Too much selenium may cause reversible balding and changes in the nails, give a garlic odor to the breath, and cause intestinal distress, weakness, and slowed mental functioning. Deficiency of selenium causes Keshan disease.
Quick GuideFat-Burning Foods in Pictures: Blueberries, Green Tea, and More
Subscribe to MedicineNet's Weight Loss/Healthy Living Newsletter
Nutrition and Healthy Eating Resources
Last Editorial Review: 5/13/2016