The Linus Pauling Institute's Vitamin K site has a good overview of current vit K research and benefits. I see some studies here that are mentioned at this page. Seems like all info needed is centralized in one page.
http://lpi.oregonsta...amins/vitaminK/
I like the Linus Pauling site, but another one for K2 studies and general info is:
http://www.vitamink2.org/
One other thing to consider regarding MK4 vs MK7 is bulk and pricing. MK4, if mimicking the bone studies, will be more expensive than MK-7 (I assume). And the Japanese natto studies show a benefit too. I realize it isn't exactly the same as a MK7/bone strength study, but the mechanism by which natto prevents osteoporosis would seemingly be from MK-7.
Edited by nameless, 19 November 2009 - 06:28 AM.