This systematic review suggests that supplementation with phytonadione and menaquinone-4 reduces bone loss .
In the case of the latter , there is a strong effect on incident fractures among Japanese patients
BACKGROUND Observational and some experimental data suggest that low intake of vitamin K may be associated with an increased risk of fracture .
OBJECTIVE To assess whether oral vitamin K ( phytonadione and menaquinone ) supplementation can reduce  bone loss  and prevent fractures .
Comparative efficacy of hormone replacement therapy, etidronate, calcitonin, alfacalcidol, and vitamin K in postmenopausal women with osteoporosis: The Yamaguchi Osteoporosis Prevention Study.
PURPOSE To assess the comparative effectiveness of several medications on bone mineral density , biochemical bone markers , and the incidence of vertebral fractures in postmenopausal women with osteoporosis . METHODS A total of 396 postmenopausal women , aged 50 to 75 years , were allocated r and omly to six equal-sized groups : hormone replacement therapy , etidronate , eel calcitonin , alfacalcidol , vitamin K ( menatetrenone ) , or control ( no treatment ) .  Thoracic and lumbar spine radiographs , bone mineral density at the distal radius , and markers of bone turnover were assessed at baseline and every 3 months during the 2-year study . RESULTS Compared with baseline , the 2-year mean changes in bone mineral density were 2.0 % for hormone replacement therapy , -0.5 % for etidronate , 1.6 % for calcitonin , -3.6 % for alfacalcidol , -1.9 % for vitamin K , and -3.3 % for control . Seventeen ( 26 % ) of the 66 control patients developed new vertebral fractures . Compared with controls , the relative risks of vertebral fracture were 0.35 ( 95 % confidence interval [ CI ] : 0.14 to 0.83 ) for hormone replacement therapy , 0.40 ( 95 % CI : 0.17 to 0.92 ) for etidronate , 0.41 ( 95 % CI : 0.17 to 0.93 ) for calcitonin , 0.56 ( 95 % CI : 0.26 to 1.12 ) for alfacalcidol , and 0.44 ( 95 % CI : 0.20 to 0.99 ) for vitamin K. CONCLUSION We observed significant reductions in the incidence of vertebral fractures with hormone replacement therapy , etidronate , and calcitonin , and significant improvements in bone mineral density with hormone replacement therapy and calcitonin
This systematic review suggests that supplementation with phytonadione and menaquinone-4 reduces bone loss .
In the case of the latter , there is a strong effect on incident fractures among Japanese patients
BACKGROUND Observational and some experimental data suggest that low intake of vitamin K may be associated with an increased risk of fracture .
OBJECTIVE To assess whether oral vitamin K ( phytonadione and menaquinone ) supplementation can reduce  bone loss  and prevent fractures .