When leafy green vegetables are frozen, do they lose their vitamin K? My husband tries to eat kale because he takes blood thinners and wants a good natural source of this vitamin. He read somewhere that frozen greens lose vitamin K in the freezing process—is this true?
No, leafy green vegetables do not lose their vitamin K when frozen.
In fact, ounce per ounce, frozen greens have slightly more vitamin K than fresh. This is because when greens are frozen, they lose some water, which slightly concentrates the nutrient. This is not true for all nutrients, though—certain nutrients are lost with the water, such as vitamin C.
Best of luck with the greens!