1, the internal organs are rich in iron. For example, the liver can help people with iron deficiency anemia to supplement iron, because the purple color of the internal organs is brought by "heme". "Heme" is the reason why viscera, muscles and blood are red, and its molecules contain iron. The color of viscera is deep because it contains more heme than iron in meat, and the absorption and utilization rate of iron is very high.

2, the internal organs are rich in vitamins. In animals, the liver is the base camp of nutrient storage, which contains all the 13 vitamins needed by human body, among which the contents of vitamin A, vitamin D, vitamin B2 and vitamin B 12 are particularly high. Protein in liver exceeds the content of lean pork, and trace elements such as iron, zinc, copper and manganese are very rich, which is almost the most complete and abundant food in nature. In addition to the liver, the kidneys of animals also contain a lot of vitamin A and vitamin D, but the content in ordinary meat is very low.