What is Vitamin K and what does it do?
Vitamin K is a nutrient that the body needs to stay healthy. It’s important for blood clotting and healthy bones and also has other functions in the body.
What foods provide vitamin K?
Vitamin K is found naturally in many foods. You can get recommended amounts of vitamin K by eating a variety of foods, including the following:
- Green leafy vegetables, such as spinach, kale, broccoli, and lettuce
- Vegetable oils
- Some fruits, such as blueberries and figs
- Meat, cheese, eggs, and soybeans
You can find links to more food sources of vitamin K in the last section of this fact sheet, Where can I find out more about Vitamin K?
What kinds of vitamin K dietary supplements are available?
Vitamin K is found in multivitamin/multimineral supplements. Vitamin K is also available in supplements of vitamin K alone or of vitamin K with a few other nutrients such as calcium, magnesium, and/or vitamin D. Common forms of vitamin K in dietary supplements are phylloquinone and phytonadione (also called vitamin K1), menaquinone-4, and menaquinone-7 (also called vitamin K2).
Am I getting enough vitamin K?
Vitamin K deficiency is very rare. Most people in Western Europe get enough vitamin K from the foods they eat. Also, bacteria in the colon make some vitamin K that the body can absorb. However, certain groups of people may have trouble getting enough vitamin K:
- Newborns who don’t receive an injection of vitamin K at birth
- People with conditions (such as cystic fibrosis, celiac disease, ulcerative colitis, and short bowel syndrome) that decrease the amount of vitamin K their body absorbs
- People who have had bariatric (weight loss) surgery
What happens if I don’t get enough vitamin K?
Severe vitamin K deficiency can cause bruising and bleeding problems because the blood will take longer to clot. Vitamin K deficiency might reduce bone strength and increase the risk of getting osteoporosis because the body needs vitamin K for healthy bones.