Vitamin K2 Steps Into the Spotlight for Bone and Heart Health

John Watson; Reviewed by: Anya Romanowski, MS, RD


October 10, 2018

What Are K2's Proposed Benefits?

Although K2's effect has been studied across a variety of conditions, including cancer and arthritis, to date the strongest evidence exists to support its use in osteoporosis and cardiovascular health.[5]

Bone Health

Vitamin K's bone-building reputation is well earned, as it is necessary for activating proteins secreted by osteoblasts.[2] K2 draws calcium into the bone matrix and can inhibit bone resorption when administered with vitamin D3.[2] The MK-7 form of vitamin K2 has proven particularly adept in this process.[6]

Supplemental K2 has been associated with significant reductions (approximately 25%-80%) in fracture risk when used alone or combined with vitamin D and calcium,[7,8] as well as with maintenance of bone density in osteoporotic patients.[9,10] K1 supplementation has shown comparatively less benefit for such outcomes.[11]

A 2017 systematic literature review recommended considering K2 alongside vitamin D and calcium as an adjunct osteoporosis treatment "rivaling bisphosphonate therapy without toxicity."[11]

Cardiovascular Disease

K2 activates matrix Gla protein (MGP), which keeps calcium deposits from forming on vessel walls. Research has shown that adequate K2 intake generally frees calcium up for its more beneficial roles, whereas K2 deficiencies will lead to a buildup of calcifications.[5]

This simple cause-and-effect relationship was on display in the 2004 prospective population-based Rotterdam Study, which included 4807 individuals with no history of myocardial infarction.[12] After following the cohort for up to 7 years, researchers reported that high K2 intake led to significant risk reductions in coronary heart disease, all-cause mortality, and severe aortic calcification when compared with those with the lowest K2 intake. In comparison, K1 intake had no discernible protective benefits.

A cohort study of over 16,000 women free of cardiovascular disease also reported a strong correlation between increased K2 intake and reduced coronary events, but not for K1.[13]


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