Vitamin K (Naphthoquinone)

Vitamin K are human vitamins, and thus is only soluble in fats and not water. They are needed for the posttranslational modification of certain proteins, a chemical modification of a protein after its translation. Vitamin K is also mostly required for blood coagulation.

Blood coagulation is a process which blood forms solid clots when the damaged blood vessel are covered by fibrin to stop hemorrhage which aids the repair of the damaged blood vessel. Disorders in coagulation may be due to the lack of Vitamin K and thus leading to the increased hemorrhaging of blood vessels.

Vitamin K is normally produced by bacteria in the intestines. A deficiency is extremely rare unless the intestines are seriously damaged.