What Are the Functions of Vitamin K in the Body

What Are the Major Functions of Vitamin K?

• Blood coagulation. Blood coagulation is required to stop bleeding after injury. Vitamin K is an essential cofactor for enzymes participating in the blood coagulation process. Vitamin K deficiency can adversely affect blood coagulation and bring about uncontrollable bleeding. 

• Bone density. Vitamin K helps maintain bone health. Supplementation with vitamin K augments bone density and curtails the risk of bone fractures in patients with osteoporosis.

• Calcification of blood vessels. Vitamin K enhances the activity of matrix Gla proteins, which inhibit calcification of blood vessels and prevent the formation of atherosclerosis.

Vitamin K is the anticoagulation vitamin.

In 1929, Henrik Dam used oil to extract and remove all lipid-soluble substances from animal feed so that it contained only water-soluble substances and then fed that to chickens. He found that the chickens suffered muscle bleeding and slow blood coagulation. Apparently, some molecule in the lipid-soluble substances was important for blood clotting.

In 1935, Dam isolated a lipid-soluble substance from the animal feed and called it vitamin K. K came from the first letter of the German word Koagulation, meaning "blood clotting." In subsequent years, scientists confirmed that the chemical structure of vitamin K was phylloquinone. Lipid-soluble vitamin K is an essential nutrient for blood coagulation in the body. Vitamin K consists of a group of structurally related naphthoquinones.

Among them, vitamins K1 and K2 are most important to human health. Vitamin K1, also known as "phylloquinone," comes from plant-based foods, particularly dark-green leafy vegetables. Vitamin K2, also known as "menadione," is produced mainly by bacteria living in the human colon.