Vitamin K is a fat-soluble vitamin. The “K” is derived from the German word “koagulation.” Coagulation refers to the process of blood clot formation. There are two naturally occurring forms of vitamin K, vitamin K1, and vitamin K2.
Purpose: Experts say vitamin K is crucial for proper blood coagulation (clotting) – it helps make 4 of the 13 proteins required for blood clotting. It is also involved in maintaining good bone health as we age.
Your body needs vitamin K to use calcium to build bone. People who have higher levels of vitamin K have greater bone density, while low levels of vitamin K have been found in those with osteoporosis.
Sources: Good sources of vitamin K1 include spinach, Swiss chard, cabbage, kale, cauliflower, broccoli, Brussels sprouts, avocado, Kiwifruit, grapes, and parsley. Good sources of vitamin K2 include meat, eggs, and dairy products.
Recommended Daily Allowance: The recommended daily intake of vitamin K for men 19 years and older is 120 mcg. For women 19 years and older it is 90 mcg. My multivitamin has 25 mcg.
Because of the potential for side effects and interactions with medications, you should take dietary supplements only under the supervision of a knowledgeable health care provider. Since vitamin K is made in the intestines, antibiotics can reduce the absorption. Also blood thinning drugs might be affected.
Vitamin K deficiency is extremely rare in healthy adults. This is because in addition to foods, the bacteria in your intestines can make vitamin K.
There is controversy over the relationship of vitamin K, vitamin D, and calcium. Dr. Mercola says, “there is new evidence that it is the vitamin K (specifically, vitamin K2) that directs the calcium to your skeleton, while preventing it from being deposited where you don’t want it — i.e., your organs, joint spaces, and arteries. A large part of arterial plaque consists of calcium deposits (atherosclerosis), hence the term “hardening of the arteries.”
The lesson here is that you shouldn’t play with vitamins. If you suspect a deficiency or you want to know more about the relationship between vitamins and minerals, then do some research or ask your healthcare provider.