Role of vitamin K in the regulation of calcification

Observational studies are promising in terms of associations between vitamin K (either diet or biochemical measures) and bone health and other conditions of normal calcification in the elderly. The level of evidence from randomized, double-blind, placebo-controlled trials with phylloquinone is very limited. In contrast, there is strong evidence of a protective effect of menaquinone-4 in pharmacological doses on age-related bone loss and fracture risk. This effect appears to be enhanced by vitamin D supplementation, supportive of the premise that all studies should be considered in the context of beneficial effects of vitamin K above that attained by calcium and vitamin D supplementation alone.