Hamidi Maryam S, Cheung Angela M
Osteoporosis and Women's Health Programs, University Health Network, Toronto, Ontario, Canada.
Mol Nutr Food Res. 2014 Aug;58(8):1647-57. doi: 10.1002/mnfr.201300950. Epub 2014 Jun 23.
Aside from its important role in blood clotting, vitamin K is an important dietary factor in regulating bone and cartilage mineralization. The vitamin K requirements to maintain musculoskeletal health may be more than the current recommendations and subclinical vitamin K deficiency may be involved in the pathogenesis of osteoporosis and osteoarthritis. Observational studies suggest that diets low in vitamin K are associated with increased risk of fractures and osteoarthritis in older adults. However, so far randomized controlled trials of vitamin K supplementation in Caucasian populations have not shown clinically significant improvements in bone mineral density at major skeletal sites. Supplementation with vitamin K may reduce the risk of fractures, but this conclusion comes from clinical trials with methodological limitations. At this time, only one randomized controlled trial has examined the effect of vitamin K supplementation on radiographic hand osteoarthritis and found no overall effect. Large well-designed randomized controlled trials are needed to compare the efficacies of vitamin K1 and K2 on fractures and osteoarthritis among older adults. In summary, currently there is not enough evidence to recommend the use of vitamin K supplements for the prevention of bone loss, fractures, or osteoarthritis in postmenopausal women.
除了在血液凝固中发挥重要作用外，维生素K是调节骨骼和软骨矿化的重要饮食因素。维持肌肉骨骼健康所需的维生素K量可能超过目前的建议量，亚临床维生素K缺乏可能与骨质疏松症和骨关节炎的发病机制有关。观察性研究表明，维生素K含量低的饮食与老年人骨折和骨关节炎风险增加有关。然而，到目前为止，在白种人群中进行的维生素K补充剂随机对照试验尚未显示主要骨骼部位的骨矿物质密度有临床显著改善。补充维生素K可能会降低骨折风险，但这一结论来自方法存在局限性的临床试验。目前，只有一项随机对照试验研究了补充维生素K对手部X线骨关节炎的影响，未发现总体效果。需要大型精心设计的随机对照试验来比较维生素K1和K2对老年人骨折和骨关节炎的疗效。总之，目前没有足够的证据推荐使用维生素K补充剂来预防绝经后妇女的骨质流失、骨折或骨关节炎。
