Selenium tablets can supplement selenium for the body, thereby improving the body's immune system and preventing and treating cardiovascular and cerebrovascular diseases to a certain extent; Selenium has anti-cancer effects. If the human body lacks selenium, it is easy to suffer from liver cancer, lung cancer, stomach cancer, as well as esophageal cancer, and so on; It has both antioxidant and anti-aging effects, and can regulate the absorption and utilization of vitamins A, C, E, and K.