Vitamin K2 (MK-7)
Menaquinone-7 (MK-7) is the long-chain form of vitamin K2 that activates matrix Gla-protein & osteocalcin, directing calcium to bone rather than arterial walls; evidence from RCTs demonstrates preservation of bone mineral density & reduction of vertebral height loss in postmenopausal women.
Evidence last reviewed: 04 Apr 2026
The evidence shows that MK-7 can significantly improve bone mineral density and reduce fracture risk in postmenopausal women. While the studies are moderate in strength, they highlight its potential benefits, particularly in this demographic.
Bone mineral density & vertebral fracture preventionHealthy postmenopausal women · RCTModerate
A 3-year double-blind RCT (n=244) of MK-7 180 mcg/day found significantly attenuated age-related decline in bone mineral content & BMD at lumbar spine & femoral neck versus placebo, plus reduced vertebral height loss in the lower thoracic region; bone strength indices were also favorably affected.
Fracture incidence & bone density in postmenopausal osteoporosisPostmenopausal women with or at risk for osteoporosis · systematic review and meta-analysis of RCTsModerate
Meta-analysis of 16 RCTs (n=6,425) found vitamin K2 supplementation significantly improved lumbar spine BMD & reduced fracture incidence after exclusion of one outlier study; undercarboxylated osteocalcin was consistently reduced, indicating enhanced bone mineralization.
Forms & usage▾
Take 180 mcg daily, preferably with a meal for better absorption.