At present, the daily recommended amount of vitamin K is only based on the requirements of vitamin K1 for proper coagulation, and the recommended amount of vitamin K1 is 1mcg / kg / day. However, these amount of vitamin K1 is not enough to maintain the optimal function of vitamin K-dependent proteins in other tissues, such as bone and vascular system. This is because the half-life of vitamin K1 is short, or its biological activity is low. Thus the recommended dose cannot reach these peripheral tissues.

Studies have shown that vitamin K2 (menaquinone-7, MK-7) is effective at very low doses, and experts recommend taking only 45 mcg per day to maintain healthy bone and cardiovascular health.

However, in a recent study that published in the International Journal of osteoporosis, 244 healthy postmenopausal women daily took 180 mcg vitamin K2 (menaquinone-7, MK-7) for three years. The researchers found that taking vitamin K2 was statistically significant in preventing cardiovascular deterioration and improving bone status. (Note: MK-7 at 180 mcg / day is considered to be a "nutritional dose", which means that this dose of vitamin K2 can be taken from a healthy point of view.)