The association between vitamin K₂, or menaquinone, and cardiovascular health continues to grow. Two recent studies involving almost 17,000 postmenopausal women suggest that increased vitamin K₂ intake, particularly of the longer chained menaquinones like menaquinone-7 (MK-7), promotes healthy vascular calcium balance and cardiovascular function. Vitamin K₁ did not have a similar effect. MK-7 is found naturally in the fermented soy product natto and has unique properties compared to other forms of vitamin K. In contrast to vitamin K1 which concentrates in bone, MK-7 concentrates in vascular tissue. It also has a much longer half-life, allowing for sustained activity. MK-7 supports the carboxylation of matrix Gla-protein (MGP), a key protein involved in calcium balance. As a result, it supports healthy arterial blood flow and vascular elasticity. Optimal serum levels of vitamin D are also important to maintain healthy calcium balance in vascular tissues, in part by supporting the activity of MGP. Studies indicate that the combination of vitamins K and D provides synergistic support. Vitamin K supplementation may be contraindicated for those taking Coumadin/warfarin anticoagulant medication. Cardio K/D liquid provides powerful support for arterial health and cardiovascular function.