7 Reasons Not to Take Vitamin K with D If it isn’t clear from the title of my blog yet, I’ll make it clear. I don’t normally recommend combo supplements of vitamin D3 with vitamin K (either K1 or K2). I get asked all the time why my brand of D3 doesn’t have K in it, and it would have been cheap and easy to put it in there but I chose not to, because of SO many reasons which I’ll discuss today, but mainly because the combination can increase risk of kidney stones (within a few years) and may...