Selenium, immune function and resistance to viral infections

Selenium (Se) is an essential micronutrient that, through its incorporation into selenoproteins, plays a pivotal role in maintaining optimal health. insufficient intake of Se enhances predisposition to diseases associated with oxidative stress to cells and tissues while supplementation above the recommended levels has been shown to confer health benefits such as enhanced immune competence and resistance to viral infections and in animal models and human studies. Recent studies have also shown that different sources of Se differ in their bioavailability and bioactivity and that Se-enriched milk may be a superior source of Se. In this paper, we briefly describe the nature of selenoproteins, sources of Se in diets and the known mechanisms by which Se/selenoproteins regulate redox balance, augment immune function and mediate resistance to viral infections.