Vitamin K

Vitamin K is a fat-soluble vitamin, so your body stores it in fat tissue and the liver. It is best known for its role in helping blood clot, or coagulate, properly. The "K" comes from its German name, Koagulationsvitamin. Vitamin K also plays an important role in bone health.

It is rare to have a vitamin K deficiency. That’s because in addition to being found in leafy green foods, the bacteria in your intestines can make vitamin K. Sometimes taking antibiotics can kill the bacteria and lead to a mild deficiency, mostly in people with low levels to begin with. Vitamin K deficiency can lead to excessive bleeding, which may begin as oozing from the gums or nose. Other things that may lead to vitamin K deficiency include:

Other conditions that benefit from vitamin K include:

Excessive Bleeding

Vitamin K is used to reduce the risk of bleeding in liver disease, conditions where your body doesn’t absorb enough vitamin K, or if you take antibiotics for a long time.

In the U.S., Canada, Great Britain, and many other countries, all newborns receive vitamin K injections to prevent the possibility of bleeding, particularly in the brain. Babies are born without any bacteria in their intestines and do not get enough vitamin K from breast milk to tide them over until their bodies are able to make it.

Even though vitamin K deficiency in newborns is very rare, it is dangerous enough that doctors give the injections. Newborns at greatest risk for vitamin K deficiency are premature or those whose mother had to take seizure medications during pregnancy. Mothers on seizure medications are often given oral vitamin K for 2 weeks before delivery.

Osteoporosis

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. Similarly, some studies suggest that low levels of vitamin K are associated with a higher risk of osteoarthritis.

There is increasing evidence that vitamin K improves bone health and reduces the risk of bone fractures, particularly in postmenopausal women who are at risk for osteoporosis. In addition, studies of male and female athletes have also found that vitamin K helps with bone health. However, some studies have found that vitamin K didn’t help with bone density.

I Would Like to Learn About:

Related Information

Supplements with Similar Uses

View List by Use

Supplements with Similar Warnings

View List by Warning

Uses of this Supplement

Bone cancer Cirrhosis Cystic fibrosis Kidney stones Myeloproliferative disorders Osteoporosis Wounds

Drugs that Deplete this Substance

View List

Learn More About

Nutrition

Review Date: 7/16/2013  

Reviewed By: Steven D. Ehrlich, NMD, Solutions Acupuncture, a private practice specializing in complementary and alternative medicine, Phoenix, AZ. Review provided by VeriMed Healthcare Network.

Learn more about A.D.A.M.'s editorial policy, editorial process and privacy policy.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- 2022 A.D.A.M., a business unit of Ebix, Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

A.D.A.M. content is best viewed in IE9 or above, Firefox and Google Chrome browser.