Abstract: Selenium-rich foods serve the dual-function of providing nutrients and organic selenium. In the situation of selenium deficiency in the entire population, it is crucial to understand the sources of selenium and its circulation in the natural environment and biological systems. Current research on selenium-rich foods focuses mostly on chemical synthesis and bio-organic conversion, which is highly specialized and not suitable for horizontal comparison of different selenium-rich foods. There are few studies on the circulation of selenium and the selenium contents and health benefits of different selenium-rich foods. This article summarizes the sources, circulation and metabolism of selenium, the sources and forms of natural selenium in selenium-rich foods, and the selenium absorption and metabolism pathways in plants, animals, and microorganisms. Next, it reviews the current status of research on selenium-rich foods from various sources, and gives an outlook on the future of selenium-rich foods. This review may serve as a foundation for in-depth comparison of selenium-rich foods from various sources, and provide scientific guidance for the research and development of novel healthy selenium-rich foods.

Key words: selenium-rich foods; selenium cycling; edible mushrooms; physiological metabolism