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Vitamin K

Source: MedlinePlus Health Topics, U.S. National Library of Medicine

Last synced 8/7/2026Status: primary verified

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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This information is for general education and is not medical advice. Always talk to a licensed U.S. clinician about your situation, medications, or treatment decisions.