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In an ideal world, Vitamin K2 would have the same association with cardiovascular health that folic acid has with pregnancy. Optimal Vitamin K2 intake is crucial to avoid the calcium plaque buildup of atherosclerosis, thus keeping the risk and rate of calcification as low as possible.1-3
Matrix GLA protein (MGP)āfound in the tissues of the heart, kidneys, and lungsāplays a dominant role in vascular calcium metabolism. Its production is stimulated by Vitamin D3, but it requires adequate Vitamin K2 intakes to be activated (similar to the bone-building protein osteocalcin). Once activated by Vitamin K2, MGP can bind calcium and escort it out of the areas where this mineral is destructive, namely arteries and soft tissues.1,4
No other productive mechanism for maintaining flexible blood vessels walls has been discovered, which makes MGP the only known and most potent existing inhibitor of cardiovascular calcification.
That is why Vitamin K2 is crucial as a cardiovascular health nutrient. Here we will endeavor to clear up considerable confusion about Vitamin K2, ensuring the right form is identified, as well as provide the substantial body of evidence confirming its role as a cardiovascular-support nutrient.
Why Vitamin K2 as MK-7 Matters Most
Vitamin K is a family of vitamins, the most important being Vitamins K1(phylloquinone) and K2 (menaquinones). Think of them as fraternal twins. They have similarities, such as working in the liver for blood clotting, and chemically they share a quinone ring called menadione.

But that is where their similarities end.
Vitamin K2 has several molecules, called menaquinones, which make K2 available beyond the liver for other systems. Vitamin K1 is the principle source of dietary Vitamin K and is needed for proper blood coagulation. Meanwhile, Vitamin K2 is essential to avoid calcium deposits in the arteries as well as to build and maintain strong bones. (A more detailed breakdown of Vitamin K1 and Vitamin K2, is in the review paper, āVitamin K: Double Bonds beyond Coagulation Insights into Differences between Vitamin K1 and K2 in Health and Disease,ā published in The International Journal of Molecular Sciences.5)

Not all forms of Vitamin K2 are created equal. The two most commonly commercialized forms of Vitamin K2 are MK-4 and MK-7. Due to its side chain, MK-7 has a much longer half-life in the body than MK-4, allowing it greater access to tissues beyond the liver.
Further, the serum half-life of MK-4 has been shown to last a few hours compared to a 3+ day half-life for MK-7.
So although they have the same molecular mechanism of action, MK-7 is more bioavailable than MK-4. And due to MK-4ās short half-life and poor bioavailability, it requires multiple doses per day at milligramlevelsāversus MK-7ās microgram levelsāfor measurable efficacy.