The Benefits of Vitamin K2

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Vitamin K2 is a member of the vitamin K family, a class of nutrients involved in blood clotting and maintaining bone health. Found naturally in meats, cheeses, and eggs, vitamin K2 (also referred to as menaquinone) is also synthesized by bacteria. In addition, many people take vitamin K2 in supplement form.


In alternative medicine, proponents claim that vitamin K2 can help with a number of health problems, including heart disease and osteoporosis. Additionally, vitamin K2 is said to protect against some forms of cancer.

Health Benefits

Here's a look at some key study findings on the health benefits of vitamin K2:

1) Heart Disease

A number of studies suggest that a high intake of vitamin K2 may reduce your risk of heart disease. In a 2004 study from the Journal of Nutrition, for instance, researchers analyzed the dietary intake of vitamin K1 and vitamin K2 among 4,807 people and found that those with the highest intake of either form of vitamin K had a significantly lower risk of coronary heart disease and atherosclerosis. In addition, study members with the highest intake of vitamin K2 were significantly less likely to die from heart disease.

What's more, a 2010 research review published in the journal Maturitas found that vitamin K2 may help protect against cardio-metabolic disorders (such as heart disease, type 2 diabetes, and metabolic syndrome). In their analysis of five studies on vitamin K consumption and incidence of cardio-metabolic disease, the review's authors also found that vitamin K1 may not protect against such disorders.

2) Bone Health

There's some evidence that K2 may boost bone health and reduce risk of osteoporosis. For a 2004 report from Current Pharmaceutical Design, scientists sized up the available research on vitamin K2 and osteoporosis. Results revealed that vitamin K2 may stimulate bone formation and suppress age-related breakdown of bone. Vitamin K2 also appears to sustain bone mineral density and prevent osteoporotic fractures in patients with age-related osteoporosis.

In a more recent research review published in Current Drug Safety, researchers found that combining vitamin K2 with bisphosphonate (a class of drugs that prevent the loss of bone mass) may be useful for preventing fractures in postmenopausal women with osteoporosis and vitamin K deficiency.

3) Cancer

Preliminary research indicates that vitamin K2 may aid in the treatment of some forms of cancer. For example, in a 2003 test-tube study from the International Journal of Oncology, researchers found that vitamin K2 may help promote the death of lung cancer cells.

Vitamin K1 vs. Vitamin K2

Vitamin K1 (also known as phylloquinone) is the form of vitamin K found in plants. Vitamin K is also available in the form of vitamin K3 (also known as menaphthone or menadione).

According to the National Institutes of Health, vitamin K1 is faster-acting, stronger, and more effective for some conditions than other forms of vitamin K. Still, some research suggests that intake of vitamin K2 may offer certain health benefits.


Taking high amounts of any form of vitamin K may be harmful to pregnant and breastfeeding women, patients receiving dialysis treatments due to kidney disease, and people with clotting problems caused by severe liver disease. In addition, vitamin K may interact with certain supplements (including coenzyme Q10 and vitamin E). 

How to Use It for Health

There are currently no widespread recommendations for vitamin K supplementation. While vitamin K2 may help with certain health problems, self-treating a chronic condition with vitamin K2 and avoiding standard care may have serious health consequences. Before you begin using vitamin K2, talk to your doctor to determine a safe and effective dosage.

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