High dose Vitamin K1 and K2 (as Menaquinone 4) may reverse calcification in the arteries
Vitamin K1 (also known as Phylloquinone and Phytonadione) is found in green leafy vegetables such as broccoli, lettuce and spinach; K1 makes up about 90% of the vitamin K in our diet. Most forms of Vitamin K2 are formed by healthy bacteria in our intestines. Different versions of Vitamin K2 are referred to as Menaquinone with various numbers after it; they make up about 10% of our Vitamin K intake. The bacteria do not make Menaquinone-4 but a small amount is found in meat. Menaquinone-7 is from fermented foods such as Natto.
Calcification of the arteries is a major part of arterial disease and hardening of the arteries. Hardening of the arteries is a key part of cardiovascular disease and coronary heart disease; the cause of over 50% of all deaths in the USA. The level of calcification of blood vessels predicts future stroke and heart attack risk.
In this study researchers from Maastricht University in the Netherlands fed 10 week old rats a higher dosage of the blood thinner warfarin (Coumadin) to cause a build up of calcium in their blood vessels for a six-week period. Vitamin K intake was at normal dietary levels at this point. Warfarin at high doses can contribute to calcification by inactivating Vitamin K dependent matrix GLA protein. Matrix GLA protein helps keep calcium out of the arteries and brings it to the bone where it belongs. The animals were then supplemented with either high dose K1 or K2 as Menaquinone-4 for an additional six-weeks.
If warfarin was stopped, calcification continued to occur over the next six-weeks at normal Vitamin K levels. However, with the removal of warfarin and the start of the high dose Vitamin K therapy the further accumulation of calcification in the arteries was stopped. In fact it was better than this; adding high dose Vitamin K reversed existing arterial calcifications by 37% within six-weeks. The higher levels of Vitamin K were needed to reactivate matrix GLA protein (a normal level of Vitamin K intake was not protective because it could not restart the matrix GLAS protein). The study appears in the April 1st, 2007 issue of the journal Blood.