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How Vitamin K Works


What Is Vitamin K?
Vitamin K plays a very important function in the body -- helping blood to clot and assisting calcium retention, which helps prevent osteoporosis. Yet its value as a vitamin wasn't always known.

The importance of a dietary factor in blood clotting was first recognized by a Danish scientist. In 1929, he reported that chicks fed diets lacking a particular dietary factor hemorrhaged. Their blood was slow to form the clots needed to control bleeding. The missing factor was vitamin K.

People who have trouble absorbing fat and, therefore, vitamin K, along with those on long-term antibiotic therapy, may need to take vitamin K supplements. When blood clotting time is slow, vitamin K is given before surgery to avoid excessive bleeding.

Vitamin K helps blood clot.
©2007 Publications International, Ltd.
Vitamin K helps blood clot and helps bones to hold on to calcium.

Because of vitamin K's ability to help produce osteocalcin, it helps the bones to hold onto calcium, possibly preventing osteoporosis.

Occasionally women who have heavy menstrual periods get relief from supplementing their diet with vitamin K. Even if their blood levels of this vitamin are in the normal range, supplements reduce the excessive bleeding in some women.

Some small studies have also shown a benefit for pregnant women. Small supplemental doses, about 50 mg, often reduces the nausea associated with the first trimester of pregnancy.

Vitamin K can be found in several foods. We'll discuss which foods are best and how much you need in the next section.

Vitamin K is a huge help to they body via blood clotting, but there are other vitamins you may want to learn about as well.
  • Vitamin A is the vitamin found in carrots that improves eyesight. Learn more about this key vitamin in How Vitamin A Works.
  • Vitamin B3, also called niacin, assists other substances in the conversion of protein, carbohydrate and fat into energy. Learn more in How Vitamin B3 Works.
  • How Vitamin C Works will show you how this vitamin can strengthen your immune system.Discovered only about 60 years ago, Biotin assists in several metabolic reactions. Learn more about it in How Biotin Works.
  • Vitamin B12 has a a chemical structure much more complex than that of any other vitamin. Learn about this vitamin How Vitamin B12 Works.
  • To learn about the many vitamins in our diet, how much you should be eating, and where to find them, go to our general Vitamins page.
  • Find the best prices on vitamin K supplements.
This information is solely for informational purposes. IT IS NOT INTENDED TO PROVIDE MEDICAL ADVICE. Neither the Editors of Consumer Guide (R), Publications International, Ltd., the author nor publisher take responsibility for any possible consequences from any treatment, procedure, exercise, dietary modification, action or application of medication which results from reading or following the information contained in this information. The publication of this information does not constitute the practice of medicine, and this information does not replace the advice of your physician or other health care provider. Before undertaking any course of treatment, the reader must seek the advice of their physician or other health care provider.