Journal of Clinical Densitometry
Maryam S. Hamidi1,
Angela M. Cheung1, 2, angela.m.cheung at gmail.com
1 Osteoporosis and Women's Health Programs at University Health Network, Toronto, ON, Canada
2 Department of Medicine at University of Toronto, Toronto, ON, Canada
Vitamin K has been purported to play an important role in bone health. It is required for the gamma-carboxylation of osteocalcin (the most abundant noncollagenous protein in bone), making osteocalcin functional.
There are 2 main forms (vitamin K1 and vitamin K2), and they come from different sources and have different biological activities. Epidemiologic studies suggest a diet high in vitamin K is associated with a lower risk of hip fractures in aging men and women.
However, randomized controlled trials of vitamin K1 or K2 supplementation in white populations did not increase bone mineral density at major skeletal sites.
Supplementation with vitamin K1 and K2 may reduce the risk of fractures, but the trials that examined fractures as an outcome have methodological limitations.
Large well-designed trials are needed to compare the efficacies of vitamin K1 and K2 on fractures. We conclude that currently there is not enough evidence to recommend the routine use of vitamin K supplements for the prevention of osteoporosis and fractures in postmenopausal women.
Address correspondence to: Angela M. Cheung, MD, PhD, Osteoporosis and Women's Health Programs, University Health Network, 200 Elizabeth Street, 7 Eaton North – Room 221, Toronto, ON M5G 2C4, Canada.
Sections of the paper
Forms and Dietary Sources of Vitamin K
Vitamin K Deficiency
Vitamin K Supplements
Vitamin K and Bone Metabolism
The Associations Between Vitamin K and BMD and Fractures: Observational Studies
The Effects of Vitamin K Supplementation on BMD and Fractures: Clinical Trials and Their Meta-Analyses
Methodological Limitations of the Current Evidence
Safety and Adverse Effects of Vitamin K Supplements
Gaps in Knowledge and Future Research
- Vitamin K2-7 helps bone, blood vessels, cancer, diabetes, etc. – June 2022
- Role of Vitamin K in Bones and Muscles - Feb 2022
- Bone loss results in blood vessel plaque if low Vitamin K2, less bone loss if high K2– April 2021
- Bone increased : Stiffness (Vitamin D), Flexibility (Vitamin K2) – Sept 2020
- Bone quality improved 2X by Vitamin D plus Vitamin K2 (trend) – meta-analysis March 2020
- Vitamin D and Calcium do not increase bone density (also need exercise, Mg, K2, protein etc.) – RCT Aug 2019
- Vitamin K (any amount and any kind) reduced bone fractures by 24 percent – meta-analysis – May 2019
- Calcium Supplementation is OK provided you also take Vitamin K – Feb 2019
- Hard bones, soft arteries, rather than vice versa (Vitamin D and Vitamin K) – March 2016
- Many seniors do not get enough protein, Vitamin D, Mg, etc. needed for bones – Feb 2019
- Adding just vitamin D again failed to add bone density (also need Magnesium, Vitamin K, etc) – RCT Aug 2018
- Osteocalcin – overview of the hormone needed to build bones, etc. Jan 2018
- Vitamin K and bone – review Oct 2017
- Bone formation in the lab is aided by Vitamin D, Vitamin K1, and Vitamin K2 – meta-analysis Nov 2017
- Better bones again associated with higher vitamin K intake – Nov 2015
- Vitamin K-2 – bone biomarkers indicate at least 600 ug of MK-4 are needed daily – Sept 2014
- Vitamin K2 (as MK-7) is needed for bone quality – Review Feb 2013
- Increased Vitamin K2 reduces the problems of excess Calcium – Nov 2013
- Vitamin K and bone health – need more research Oct 2013
- Vitamin K-2 (180 ug MK-7) helped both bone density and strength – RCT March 2013
- Healthy bones need Ca, Silicon, Vitamins B, C, D, and K – Dec 2012
- Increasing bone mineral density increases breast cancer by at least 2X – Aug 2012
- Healthy bones need: Calcium, Vitamin D, Magnesium, Silicon, Vitamin K, and Boron – 2012
- Vitamin D, K2, Magnesium, etc increase bone density when taking together– Jan 2012
- BONE SPURS not produced if have enough Vitamin D3, Vitamin K2, etc. – Nov 2011
- Vitamin K1 reduced hip fracture but Vitamin K2 did not – Aug 2011
- Women with hip fractures very low on vitamins D3 and K – Mar 2011
- Vitamin K2 from natto improved bone mineral density – March 2011