1 interaction related to spinach
Spinach is one of the highest dietary sources of vitamin K1 (phylloquinone), with roughly 145 mcg per cup raw and 889 mcg per cup cooked. Because warfarin works by blocking vitamin K-dependent clotting factor synthesis, large or fluctuating spinach intake antagonizes warfarin and can drop the INR into a sub-therapeutic range, raising clot risk.