Blueberry Naturals Vitamin D3 + K2 helps you get adequate amounts of vitamin D and vitamin K that is essential for your health. Vitamin D3 + K2 is a powerful combination for supporting bone health as well as cardiovascular health. Vitamin K2 is of particular importance because of its role in bone metabolism and cardiovascular health. Vitamin D3 ensures that calcium is absorbed easily and K2 (MK-7) activates the protein, osteocalcin, which integrates calcium into bone. Vitamin D3 and vitamin K2 ensure that calcium is absorbed easily and reaches the bone mass, while preventing arterial calcification.