Vitamin K

› Health benefits

Scientists are studying vitamin K to understand how it affects our health. Here are some examples of what this research has shown.

Osteoporosis
Vitamin K is important for healthy bones. Some research shows that people who eat more vitamin K-rich foods have stronger bones and are less likely to break a hip than those who eat less of these foods. A few studies have found that taking vitamin K supplements improves bone strength and the chances of breaking a bone, but other studies have not. More research is needed to better understand if vitamin K supplements can help improve bone health and reduce osteoporosis risk.

Coronary heart disease
Scientists are studying whether low blood levels of vitamin K increase the risk of coronary heart disease, perhaps by making blood vessels that feed the heart stiffer and narrower. More research is needed to understand whether vitamin K supplements might help prevent heart disease.

› How much do I need

The daily amount of zinc needed depends on age and gender. Adults age 19-plus: 120 micrograms (mcg) daily for men and 90 micrograms for women.

Vitamin K deficiency is very rare. Most people in the United States 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.

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.

› In food

Vitamin K is found naturally in many foods. You can get recommended amounts of vitamin K by eating a variety of foods, including green leafy vegetables, such as spinach, kale, broccoli and lettuce; vegetable oils; some fruits, such as blueberries and figs; meat, cheese, eggs and soybeans.

› Dietary supplements

Vitamin K is available most commonly in capsules and soft gels. It 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).

Source: National Institutes of Health, Office of Dietary Supplements

Please consult your health care provider before making changes to your vitamin/supplement regimen.