How Selenium Protects Against Viral Infections and Mutations
Selenium is an essential micronutrient that is important for immune response, thyroid health, oxidative damage prevention, and many other functions. Selenium from our diet replaces a sulfur atom in the amino acid cysteine to form selenocysteine, which is then incorporated into selenoproteins. There are 25 known selenoproteins, with most of them exhibiting antioxidant properties such as glutathione peroxidase (GPx). Viruses produce reactive oxygen species (ROS) which are combated by GPx and other selenoproteins to slow down viral replication and mutations [1,2]. Studies using mice have shown that viral symptoms and infection times are more severe when dietary selenium is deficient, and that low selenium intake results in decreased GPx activity [3,4]. While selenium may not be the only nutrient that slows or prevents viral damage and mutation, adequate selenium nutrition should be considered as a defense against viral infectious diseases.
In a nutshell, selenium deficiency → increased viral oxidative stress/inflammation → increased viral damage and mutations → new viral strains.