Is Your K Okay?

 

Vitamin K refers to a group of fat-soluble vitamins that play a role in blood clotting, bone metabolism, and regulating blood calcium levels. Vitamin K1, or phylloquinone, comes from plants. It is the main type of dietary vitamin K. A lesser source is vitamin K2, or menaquinone, which occurs in some animal-based and fermented foods. Deficiency is rare, but, in severe cases, it can increase clotting time, leading to hemorrhage and excessive bleeding. A deficiency can also compromise cognitive function, heart health and mobility so it is a particular concern as we age.

The recommended daily intake is 120mcg for men and 90mcg for women. Most Americans are not at risk of a vitamin-K deficiency but older adults, particularly men, are the age group most likely to come up short. One cup of dark, leafy greens will provide you with plenty and, being fat-soluble, consuming it with some fat will enhance absorption.

Collard greens are the Vitamin K champions, with one cup providing over 770mcg. Other powerful sources include kale, broccoli, Brussels sprouts and spinach. One cup of any of these will provide more than your daily requirement. Asparagus, green beans, bok choy, avocado and lettuce are also good sources.

Since Vitamin K promotes blood clotting, so you may need to limit your intake a bit if you use the blood thinner warfarin. But don't avoid Vitamin K rich foods entirely as they supply many other important nutrients. And newer anticoagulants are not affected by Vitamin K.