I couldn't find anything on preventing kidney stones but I may need to do more digging. Not saying there isn't evidence but I haven't found any. Yet.
I've only begun recently learning about it to help someone else. It also helps me to solidify knowledge by typing things out. For starters, K1 is the one more associated with coagulation; K2 is associated more with handling calcium.
I don't take supplements unless there is some science behind them, a deficiency or at least scientic plausability to take them. I only take prescription supplements because vitamins are not regulated in the US.
I see that in the following example: a very large dose of vit D resulted in more fractures, not less, in elderly Australian women. Therefore it seems logical that there is more to the picture to be discovered, in order to make sense. A good candidate for that missing element would be a component that shepherds calcium around. Bone is more protein than mineral, calcium doesn't home to bone by itself, vit D2 is said to activate the protein that does the shepherding.
I am very grateful that I can take the risk and have the
freedom to try something rather than being at the mercy of bureaucrats who have the power to tell me what I can take - or order us to give $100 to an MD for a presciption for vitamin C. I'd be happy to sign a form with every purchase that says only I am responsible.
I'm obviously not a fan of supplementation, think they are way overhyped and too underegulated. But that's my take.
Vit D was certainly a huge hype. I'm still waiting for news headlines that disease in the western world has declined by 70% because everybody is swilling so much of the supposed cureall vit D.
Still, sometimes a supp (such a mast cell stabilizers) )does have a great benefit (as I know personally), so while not thinking that a supp is the answer for everything, I am sometimes willing to investigate when it seems warranted - as when there is a simple and plausible mechanism as opposed to the jargon-filled multi-step parthways that always get bandied around.
I don't wait to wait for large RCTs to in effect give me permission to take something that I know works. Besides, relying on RCTs is no guarantee of anything, as seen in the recent collapse of (prescription) Niaspan use.