title: Vitamin K supplementation does not significantly impact bone mineral density and biochemical markers of bone in pre- and perimenopausal women.
abstract: Because of its role in osteoblastic metabolism, vitamin K has been studied with respect to bone. However, there has been limited research examining the influence of long-term vitamin K supplementation on bone mineral density (BMD). Therefore, the purpose of this study was to assess the impact of 6 months of vitamin K supplementation on BMD and biomarkers of bone in pre- and perimenopausal women. Based on previous work, we hypothesized that vitamin K would improve BMD and biochemical markers of bone formation. A double-blind, placebo-controlled, randomized trial is an effective way to study the impact of long-term supplementation. Thus, 14 pre- and perimenopausal women, 25 to 50 years of age, were randomly assigned to an experimental group (E) that received 600 microg/d of vitamin K in the form of phylloquinone (K(1)) or a control group (C) that received identical-looking placebo tablets. Regional BMD and percent body fat, measured by dual-energy x-ray absorptiometry, and serum osteocalcin and urinary N-telopeptide levels were all assessed at 0, 3, and 6 months. When BMD was measured across time, C had a significant increase (P = .011) in greater trochanter BMD compared to E. The E group had a nonsignificant increase (P = .067) in shaft BMD compared to the C group. There was no significant difference between E and C in serum osteocalcin concentrations over time. Urinary N-telopeptide levels increased significantly over time in E compared to C (P = .008). Six months of 600 microg/d vitamin K(1) supplementation did not improve regional BMD in this group of pre- and perimenopausal women.
authors.affiliation: Division of Biobehavioral and Health Sciences, School of Nursing, University of Pennsylvania, Philadelphia, PA 19104-6096, USA. svolpe@nursing.upenn.edu
authors.forename: Stella L
authors.initials: SL
authors.lastname: Volpe
authors.forename: May May
authors.initials: MM
authors.lastname: Leung
authors.forename: Heather
authors.initials: H
authors.lastname: Giordano
mesh_terms: D015502:Absorptiometry, Photon; D000328:Adult; D015415:Biomarkers / Q000032:analysis*; D050218:Body Fat Distribution; D015519:Bone Density / Q000187:drug effects*; D001842:Bone and Bones / Q000378:metabolism*; D024042:Collagen Type I / Q000652:urine; D004032:Diet; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008875:Middle Aged; D015675:Osteocalcin / Q000097:blood; D010455:Peptides / Q000652:urine; D047648:Perimenopause; D010919:Placebos; D014812:Vitamin K / Q000008:administration & dosage*; D010837:Vitamin K 1 / Q000008:administration & dosage
chemical_list: D015415:Biomarkers; D024042:Collagen Type I; D010455:Peptides; D010919:Placebos; C052929:collagen type I trimeric cross-linked peptide; D015675:Osteocalcin; D014812:Vitamin K; D010837:Vitamin K 1