Vitamin K – Consumer

A woman discussing supplements with a pharmacist.

This is a reader-helpful overview of Vitamin K. For extra facts, see our health skilled reality sheet on Vitamin K.

What is vitamin K and what does it do?

Vitamin K is a nutrient that the overall body desires to continue to be nutritious. It is essential for blood clotting and nutritious bones and also has other capabilities in the overall body. If you are having a blood thinner this kind of as warfarin (Coumadin®), it really is pretty essential to get about the exact same amount of vitamin K just about every day.

How a great deal vitamin K do I need to have?

The amount of vitamin K you need to have depends on your age and sex. Ordinary every day advised amounts are mentioned under in micrograms (mcg).

Lifetime Phase Encouraged Sum
Beginning to six months two. mcg
7–12 months two.5 mcg
1–3 decades 30 mcg
4–8 decades 55 mcg
9–13 decades sixty mcg
14–18 decades seventy five mcg
Adult adult males 19 decades and older a hundred and twenty mcg
Adult gals 19 decades and older 90 mcg
Expecting or breastfeeding teens seventy five mcg
Expecting or breastfeeding gals 90 mcg


What foodstuff deliver vitamin K?

Vitamin K is found in a natural way in several foodstuff. You can get advised amounts of vitamin K by ingesting a selection of foodstuff, which includes the adhering to:

  • Environmentally friendly leafy greens, this kind of as spinach, kale, broccoli, and lettuce
  • Vegetable oils
  • Some fruits, this kind of as blueberries and figs
  • Meat, cheese, eggs, and soybeans

You can obtain hyperlinks to extra meals sources of vitamin K in the final segment of this reality sheet, Exactly where can I obtain out extra about Vitamin K?

What kinds of vitamin K nutritional nutritional supplements are obtainable?

Vitamin K is found in multivitamin/multimineral nutritional supplements. Vitamin K is also obtainable in nutritional supplements of vitamin K on your own or of vitamin K with a several other nutrients this kind of as calcium, magnesium, and/or vitamin D. Typical varieties of vitamin K in nutritional nutritional supplements are phylloquinone and phytonadione (also identified as vitamin K1), menaquinone-4, and menaquinone-seven (also identified as vitamin K2).

Am I receiving enough vitamin K?

Vitamin K deficiency is pretty exceptional. Most people today in the United States get enough vitamin K from the foodstuff they eat. Also, germs in the colon make some vitamin K that the overall body can absorb. Nevertheless, specific teams of people today could have problems receiving enough vitamin K:

  • Newborns who don’t get an injection of vitamin K at beginning
  • Men and women with situations (this kind of as cystic fibrosis, celiac condition, ulcerative colitis, and shorter bowel syndrome) that lower the amount of vitamin K their overall body absorbs
  • Men and women who have had bariatric (bodyweight decline) surgical procedure

What takes place if I you should not get enough vitamin K?

Significant vitamin K deficiency can trigger bruising and bleeding issues mainly because the blood will choose for a longer period to clot. Vitamin K deficiency may well lower bone energy and enhance the chance of receiving osteoporosis mainly because the overall body desires vitamin K for nutritious bones.

What are some effects of vitamin K on health?

Scientists are studying vitamin K to comprehend how it affects our health. Right here are some examples of what this analysis has proven.


Vitamin K is essential for nutritious bones. Some analysis shows that people today who eat extra vitamin K-loaded foodstuff have more robust bones and are fewer probably to crack a hip than all those who eat fewer of these foodstuff. A several studies have found that having vitamin K nutritional supplements enhances bone energy and the probabilities of breaking a bone, but other studies have not. Additional analysis is essential to much better comprehend if vitamin K nutritional supplements can assistance make improvements to bone health and lower osteoporosis chance.

Coronary heart condition

Scientists are studying whether or not reduced blood levels of vitamin K enhance the chance of coronary heart condition, possibly by making blood vessels that feed the heart stiffer and narrower. Additional analysis is essential to comprehend whether or not vitamin K nutritional supplements may well assistance reduce heart condition.

Can vitamin K be damaging?

Vitamin K has not been proven to trigger any damage. Nevertheless, it can interact with some prescription drugs, specifically warfarin (Coumadin®)—see the info under.

Does vitamin K interact with prescription drugs or other nutritional nutritional supplements?

Certainly, some prescription drugs could interact with vitamin K. Right here are a several examples:

Warfarin (Coumadin®)

Vitamin K can have a serious conversation with the blood thinner warfarin (Coumadin®). If you choose warfarin, make positive that the amount of vitamin K you eat from meals and nutritional supplements is about the exact same each day. A unexpected modify in the amount of vitamin K you get can trigger perilous bleeding (if you eat fewer) or blood clots (if you eat extra).


Antibiotics can destroy the very good germs in your intestine. Some of these germs make vitamin K. Employing antibiotics for extra than a several months could lower the amount of vitamin K manufactured in your intestine and therefore, the amount obtainable for your overall body to use.

Bile acid sequestrants

Some people today choose bile acid sequestrants (this kind of as cholestyramine [Questran®] and colestipol [Colestid®]) to reduce blood cholesterol levels. These prescription drugs can lower the amount of vitamin K your overall body absorbs, particularly if you choose them for several decades.


Orlistat (Alli® and Xenical®) is a bodyweight-decline drug. It lowers the amount of body fat your overall body absorbs and can lower the absorption of vitamin K.

Notify your medical doctor, pharmacist, and other healthcare companies about any nutritional nutritional supplements and prescription or in excess of-the-counter medicines you choose. They can explain to you if the nutritional nutritional supplements may well interact with your medicines or if the medicines may well interfere with how your overall body absorbs, utilizes, or breaks down nutrients this kind of as vitamin K.

Vitamin K and healthful ingesting

Men and women ought to get most of their nutrients from meals and beverages, in accordance to the federal government’s Dietary Rules for Individuals. Foods incorporate nutritional vitamins, minerals, nutritional fiber, and other factors that advantage health. In some scenarios, fortified foodstuff and nutritional nutritional supplements are beneficial when it is not probable to meet up with desires for a person or extra nutrients (e.g., through precise everyday living levels this kind of as being pregnant). For extra info about building a nutritious nutritional sample, see the Dietary Rules for Individualsexternal link disclaimer and the U.S. Division of Agriculture’s MyPlate.external link disclaimer

Exactly where can I obtain out extra about Vitamin K?

  • For standard info on vitamin K:
  • For extra info on meals sources of vitamin K:
    • Business of Dietary Health supplements Overall health Expert Actuality Sheet on Vitamin K
    • U.S. Division of Agriculture’s (USDA) FoodData Centralexternal link disclaimer
    • USDA Nutrient Lists for vitamin K as both:
      • Phylloquinone, the form of vitamin K found in green leafy greens, mentioned by meals or by written content, or
      • Menaquinone, a form of vitamin K found in fermented foodstuff and foodstuff that arrive from animals, mentioned by meals or by written content
  • For extra suggestions on deciding on nutritional nutritional supplements:
  • For info about building a nutritious nutritional sample:


This reality sheet by the Business of Dietary Health supplements (ODS) provides info that ought to not choose the area of healthcare suggestions. We inspire you to communicate to your healthcare companies (medical doctor, registered dietitian, pharmacist, etc.) about your curiosity in, inquiries about, or use of nutritional nutritional supplements and what could be greatest for your general health. Any point out in this publication of a precise item or assistance, or recommendation from an firm or skilled culture, does not represent an endorsement by ODS of that item, assistance, or expert suggestions.

Updated: March 22, 2021 History of improvements to this reality sheet