National Institutes of Health
- The primary NIH organization for research on Vitamin K is the NIH Office of Dietary Supplements
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National Institutes of Health
Vitamin K
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.
Most people get their vitamin K from plants such as green vegetables, and dark berries. Bacteria in your intestines also produce small amounts of vitamin K.
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- Vitamin K(Harvard School of Public Health)
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Overviews
- Facts about Vitamin K(University of Florida, Institute of Food and Agricultural Sciences)
- Vitamin K(Merck & Co., Inc.)
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Nutrition
- Vitamin K Content of Selected Foods(Dept. of Agriculture) - PDF
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Related Issues
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Important Information to Know When You Are Taking: Coumadin and Vitamin K(National Institutes of Health, Clinical Center)
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- Also available in Spanish
- Vitamin K(American Cancer Society)
- Vitamin K Deficiency(American Association for Clinical Chemistry)
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Important Information to Know When You Are Taking: Coumadin and Vitamin K
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Clinical Trials
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ClinicalTrials.gov: Vitamin K(National Institutes of Health)
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ClinicalTrials.gov: Vitamin K
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Journal Articles
References and abstracts from MEDLINE/PubMed (National Library of Medicine)
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Directories
- Find a Registered Dietitian(Academy of Nutrition and Dietetics)
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Organizations
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Patient Handouts
- Vitamin K
- Also available in Spanish
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You may also be interested in these related encyclopedia pages:
MEDICAL ENCYCLOPEDIA