This is a question that comes up from time to time and is important, because doctors sometimes tell their patients not to eat high vitamin K vegetables, which doesn't exactly promote health. It's true that K supplements would not be advised, but the doctor will be monitoring her clotting ability, so she should eat whatever vegetables she likes and let the doctor adjust the blood thinner medications. My guess is that unless she's eating huge amounts, the vitamin K available from whole foods won't have that much effect, anyway. Interestingly, I don't ever see this question come up about fish oils, but they'll further thin the blood, and there's a balance there, too, that needs to be considered.
