January 23, 2012

149 The Rediscovery of Vitamin K2 [23 January 2012]

Vitamin K2 was first discovered 70 years ago but it is only in the last few years that its full significance is being appreciated.

In the early 1930s Danish biochemist Henrick Dam discovered a nutrient that was essential for the blood clotting process. He named it Vitamin K for “koagulation”. A decade later an American researcher Edward Doisy isolated this nutrient and identified its structure. The two researchers shared a Nobel Prize in 1943 for their discovery.

Dam and Doisy recognized two forms which they named K1 and K2, but believed them to be variations of the same nutrient with the only known function of blood clotting. It was 30 years after that, in 1975, that the K2-dependent enzyme osteocalcin was discovered. And it was another 20 years, in 1997, before researchers understood that osteocalcin was essential for deposition of calcium in bones and prevention of calcium deposits in arteries. So why haven’t we been hearing about it for the last 15 years?

The reason is that it was assumed that a K2 deficiency was rare. K1 is readily available in leafy green vegetables in sufficient amounts for clotting purposes. It was only 5 years ago, in 2007 that the extent of K2 deficiency became known. Confusion between the two forms continues, though it is now known that they are two different nutrients with entirely different functions, not just different forms of the same vitamin. Research is still coming in showing how important K2 is for our health and its role in preventing atherosclerosis, osteoporosis, dental caries, diabetes, cancer and more.

Ironically the importance of K2 and the significance of its deficiency were first written about in 1939 by dentist and nutritional researcher, Weston A. Price. He discovered that a nutrient he called “Activator X” was deficient in modernized diets, causing changes within a generation of deformed dental arches, dental caries, and other chronic diseases. From his observations we now know Price’s “X” is K2.

Source: Vitamin K2 and the Calcium Paradox by Kate Rheaume-Bleue, Bsc. ND, John Wiley & Sons, 2012. Watch a 15 minute interview with Dr Rheaume-Bleue here.

This article is intended for educational purposes only; for medical advice consult your licensed health practitioner.


  1. Sources of K2? I wonder if it is partly responsible for the high diabetes rates in some areas?

  2. Now I realized how important vitamin K2 is. Would probably eat more foods rich in this vitamin starting today. :) But how about K1 and K3? How are they helpful to the body?

  3. sorry sweetlady - I just found your comment now. K1 is the clotting vitamin that is essential for the blood clotting process. We should get adequate K1 if we eat enough leafy green veggies. K3 is a synthetic version of K1 known to cause liver toxicity so is best avoided. Stan