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URL of this page: https://medlineplus.gov/vitamink.html

Vitamin K

Summary

Vitamins are substances that your body needs to grow and develop normally. Vitamin K helps your body by making proteins for healthy bones and tissues. It also makes proteins for blood clotting. If you don't have enough vitamin K, you may bleed too much.

Newborns have very little vitamin K. They usually get a shot of vitamin K soon after they are born.

If you take blood thinners, you need to be careful about how much vitamin K you get. You also need to be careful about taking vitamin E supplements. Vitamin E can interfere with how vitamin K works in your body. Ask your health care provider for recommendations about these vitamins.

There are different types of vitamin K. Most people get vitamin K from plants such as green vegetables, and dark berries. Bacteria in your intestines also produce small amounts of another type of vitamin K.

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The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health.