Hi Madisongrrl,

This is great stuff. Thank you for sharing. Did I not see it, or is the first link/study not specify whether they administered MK4 or 7? It seems like it was a mix of K1 and K2 (ambiguously), no? The second link is clearly positive for MK4, and the last one unfavorable for MK7, no doubt.

What to conclude? I think what you say is right. My inclination now is to take both, or a supplement that has both. But there is this: http://nutritionj.biomedcentral.com/...475-2891-11-93. So if taking 4, especially if alone, I would imagine needing to supplement at higher doses, though would that be safe? But it seems like the limited research has at least raised concern regarding whether the serum availability of 7, which is clearly far superior, translates into bone availability or saturation, which is after all the real issue, right?

I wonder now if my reaction to the two supplements is to the K2, or more precisely to soy. I used to eat a ton of soy, but that was before all this. I'm curious how the Pure Encapsulations will work out - that's 7 and K1, and I imagine lanoline derived D3.

So, before sending this off, I tried to find another study, and did find a longer, three-year study and it seems quite a bit more promising: http://www.ncbi.nlm.nih.gov/pubmed/23525894. Interestingly, the total hip was once again not well served. I wonder what's going on there.

Alright, that's it for now. Thanks again for the links and the thoughts. I might think if finding something with some MK4 too, though it seems I would need a high dose. I have to do a bit more research when I have more time.