Life Extension Super K with Advanced K2 Complex formula provides vitamin K1 and the MK-4 and MK-7 forms of vitamin K2 in just one daily softgel. The virtue of this formula is that it provides the precise amount of the long-acting MK-7 form of vitamin K2 that recent human studies have shown provides optimal K2 levels over a 24-hour period. The MK-4 is included to provide the rapid increase in vitamin K blood levels that may account for its beneficial effects in certain studies. Vitamin K2 have been extensively researched and the findings reveal vastly improved effects compared to K1.