Vitamin K is well known for its role in blood clotting, but has also been found to play an important role in normal bone formation and the preservation of bone strength.* Vitamin K₂ more specifically is a significant regulator of tissue calcification and is critical for the maintenance of arterial elasticity and cardiovascular health.* Vitamin K₂ includes two of the most studied subtypes, MK-7 (menaquinone-7) and MK-4 (menatetrenone). MK-7, the most readily absorbed and bioactive form of K₂, has no common dietary sources.* Unlike vitamin K₁, which is stored in the liver, MK-7 is transported directly to tissues and has a longer half-life than either K1 or MK-4.*