In the first human study using natural vitamin K2 as a dietary supplement it was demonstrated that natural menaquinone-7 was significantly better as compared to the synthetic vitamin K1 in several important areas, including much longer bioavailability and higher efficacy levels in the blood.

Analyzing intakes of single daily doses of 100mkg, only MK-7 is effectively present in the circulation and available for absorption by various tissues during the 24 hours after intake. If taken on regular basis, only MK-7 shows asymptotic accumulation during the first two weeks, after which a steady-state level is reached.

Dose-response K1         Dose-response K2  

Dose response: curves for vitamin K1 (A-orange) and vitamin K2-MK-7 (B-green) at 4 (color dots) and 24 (white dots) after a single oral dose. At all levels of intake, MK-7 was better than K1 at raising blood levels after a single dose [13]

At comparable intakes, the final level of MK-7 was 7 to 8 fold higher than of K1, suggesting that, if taken on daily basis, 25mkg/d of MK-7 is more efficacious than 100mkg/d of K1.

Blood levels K1 vs K2

Ability of long-term administrations of MK-7 (green) versus vitamin K1 (orange) to raise serum vitamin K levels. A six-week period supplementation with MK-7 was 7 to 8 fold better at raising serum vitamin K levels, compared with a six-week period of vitamin K1 supplementation [13].