Selenium and selenoproteins: their function and development of selenium‐rich foods

Summary Selenium (Se) is a nutrient related to human physiological processes and an essential trace element that has attracted considerable attention because of its antioxidant, immune and other functions. Se deficiency can cause all sorts of diseases and dysfunctions in the human tissues, but excessive intake of Se can also cause poisoning and injury. With lower toxicity and higher utilisation than inorganic Se, organic Se is recommended in the framework of a balanced diet. Compared with pharmaceutical supplementation, dietary Se supplementation is more acceptable to the masses. Thus, Se‐rich foods and selenoproteins enriched with organic Se have become a hot spot for current research. In living organisms, Se often exists in the form of selenoproteins (more than 25); for example, selenocysteine and selenomethionine are the common chemical forms of Se amino acids. And most of Se's physiological functions depend on the participation of selenoproteins. This paper reviews the physiological processes of Se, the development and utilisation of Se‐enriched foods, and the research on the properties of selenoproteins. Some suggestions and prospects for developing Se‐rich food in the future are also provided.