Selenium is one of the essential trace elements for human body. Many experts point out that selenium plays an irreplaceable role in delaying aging, enhancing physical fitness, anti-cancer and anti-oxidation. At present, the selenium intake of Chinese population is lower than the world level, and China is a country with dietary selenium deficiency. It is suggested to increase the intake of selenium in diet. Diet is the main way for human body to absorb selenium. China, a large area from northeast to southwest, is a selenium-deficient area, so there is less selenium in our food. In addition, the food in some places is relatively simple. For example, in the Keshan disease area we found, patients mainly eat local agricultural products, and there are fewer varieties of food. The content of selenium itself is very low, and its absorption in the body is also very low, which causes the onset of Keshan disease. My87.cn Health Knowledge Network suggested that the diet should be diversified as much as possible, eat more selenium-enriched foods, and increase the supplementary intake of selenium. Rich sources of selenium are sesame, animal offal, garlic (garlic food), mushrooms, dried seaweed, fresh shellfish, mussels, Flammulina velutipes, sea cucumber, squid, amaranth, fish meal, butter (oily food), beer yeast, wheat germ and lobster. Good sources are sea crab, scallop, hairtail, pine fish, yellow croaker, lobster, sheep oil, soybean oil, pig kidney, whole grain (flour), crab, pork and mutton. Common sources are fennel, mushrooms, peach cakes, carrots, whole oat flour, beer, rice, orange juice and whole milk. Trace sources are corn, millet, walnut, cream cake, oil cake, fruit (fruit food) and sugar.