A:The total content of selenium in the bodyis 6-20mg. Selenium is spread
throughout the tissuesOrgans and body fluids, the highest concentration in the kidney, is very important to improveimmunity and prevent cancer. When selenium is lacking, it can easily lead to a decline in human immunity and a threat to human health and life.The more than 40 diseases are related to the lack of selenium in the human body,such as cancer, cardiovascular disease, liver disease, cataracts etc.