The study found very positive effects on rheumatoid arthritis (RA) using MK-4 but not K1. The dosage were on the high end, and the human equivalents would be 1.5mg/kg and 7mg/kg for the two groups. The beneficial effects on RA were highly dose-dependent. This is yet another study that hints the therapeutic value of vitamin K2 for degenerative conditions may be much higher at doses higher than 45mg daily, which is what Peat has been recommending. As I mentioned in another post, I suspect he is recommending 45mg b/c that's what most of the published human studies used. However, the original Japanese studies from the 1990s state that the dosage was in fact 1mg/kg and they ended up using a fixed dose of 45mg b/c most of their patients (elderly people with bone problems) had weights in that range (45kg-55kg).
http://onlinelibrary.wiley.com/doi/10.1002/iub.41/pdf
http://onlinelibrary.wiley.com/doi/10.1002/iub.41/pdf