Vitamin K

What is vitamin K?

Vitamin K is the blood clotting vitamin par excellence.

Vitamin K is a fat-soluble vitamin, which gets its letter from its essential role in coagulation (K for Koagulation in German).

It exists in different forms, the main ones being: vitamin K1, or phylloquinone, which is provided by the diet; vitamin K2, or menaquinone, which is produced by bacteria in the digestive tract, and which can also be found in certain foods; and vitamin K3, or menadione, which is a synthetic form, potentially toxic and therefore forbidden.

What is its function and what are its benefits?

The best known action of vitamin K is its key role in blood coagulation (and more specifically vitamin K1), but it also plays an important role in bone mineralization (and more specifically vitamin K2), by participating in the fixation of calcium on the bones.

Scientists are more and more interested in the role of vitamin K2 in the prevention of osteoporosis and cardiovascular disorders, since very recently.

It also plays a role in cell growth.

Where to find it?

Vitamin K1 is found in food, mainly in green vegetables (spinach, broccoli, cruciferous vegetables, asparagus, lettuce, parsley, artichokes, beans, leeks, peas, chard, etc.), parsnips, carrots, but also in blueberries.

Vitamin K2 is largely synthesized by intestinal bacteria, but can also be found in certain foods, such as fermented products (cheese, yogurt, milk, natto, etc.), liver, fish oils, etc.

Deficiency and excess

Excesses are relatively rare and harmless, as vitamin K is not significantly stored by the body. On the other hand, deficiencies can present serious risks, particularly for bleeding.

Needs may be increased in newborns, people with intestinal absorption problems, the elderly, chronic alcoholics, people suffering from osteoporosis, etc. Medical supervision is then necessary.