Vitamin K, contains both water-soluble and fat-soluble vitamins. Vitamin K, including vitamin K1, K2, K3, K4, its main function is as a coenzyme for the synthesis of coagulation factors. Vitamin K1, vitamin K2, are fat-soluble vitamins. Vitamin K1 is mainly found in dark green vegetables such as kale, spinach, vegetable oils, etc. Vitamin K2 is mainly synthesized by Escherichia coli bacteria, while vitamin K3 and K4 are water-soluble vitamins synthesized artificially. The intake of vitamin K for Chinese adults should be 80ug/d. Since vitamin K cannot pass through the placenta and there is no E. coli in the intestinal tract of newborns, newborns are prone to vitamin K deficiency, while adults who suffer from pancreatic and biliary tract diseases may suffer from vitamin K deficiency. It is recommended to supplement foods rich in vitamin K in the daily diet to avoid deficiencies that can lead to bleeding.