Vitamin K2 supplementation does not influence bone loss in early menopausal women: a randomised double-blind placebo-controlled trial
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Vitamin K2 may preserve bone strength and reduce fracture risk. In this randomised double-blind placebo-controlled trial among healthy postmenopausal Norwegian women, 1 year supplementation of vitamin K2 in the form of Natto capsules had no effect on bone loss rates.
Japanese studies indicate that vitamin K2 (menaquinone-7 (MK-7)) intake may preserve bone strength, but this has not been documented in Europeans. The aim of this study was to assess the effect of MK-7 on bone mineral density (BMD) changes in postmenopausal Norwegian women.
Three hundred thirty-four healthy women between 50 and 60 years, 1–5 years after menopause, were recruited to a randomised double-blind placebo-controlled trial. The participants were randomly assigned into two groups, one receiving 360 µg MK-7 in the form of Natto capsules and the other the same amount of identical-looking placebo capsules containing olive oil. BMD was measured at total hip, femoral neck, lumbar spine and total body at baseline and 12 months together with serum levels of bone-specific alkaline phosphatase, Crosslaps, total osteocalcin (N-mid OC), carboxylated (cOC) and under-carboxylated osteocalcin (ucOC).
After 12 months, there were no statistical differences in bone loss rates between the groups at the total hip or any other measurement site. Serum levels of cOC increased and ucOC decreased in the treatment versus the placebo group (p < 0.001).
MK-7 taken as Natto over 1 year reduced serum levels of ucOC but did not influence bone loss rates in early menopausal women.
KeywordsBone loss Menopause MK-7 Randomised controlled trial Vitamin K2
We are greatly thankful for the contributions from Margrete Garvik and Eva Mette Leknes at the Bone Laboratory, Marit Hjelmeland and professor Ernst Lien at the Hormone Laboratory at Haukeland University Hospital in Bergen, the chief study nurse Aslaug Jacobsen and her colleagues at the research unit at the University Hospital of North Norway, Tromsø, and to professor John Eisman at Garvan Institute of Medical Research, Sydney, for reading and critically commenting the manuscript.
The study was financially supported by grants from the Norwegian Osteoporosis Association and Northern Norway Regional Health Authorities. NATURAL provided the study medication and Eckboe’s legacy provided support for blood analyses.
Conflicts of interest
- 4.Johnell O, Kanis JA, Oden A, Johansson H, De Laet C, Delmas P, Eisman JA, Fujiwara S, Kroger H, Mellstrom D, Meunier PJ, Melton LJ III, O’Neill T, Pols H, Reeve J, Silman A, Tenenhouse A (2005) Predictive value of BMD for hip and other fractures. J Bone Miner Res 20:1185–1194CrossRefPubMedGoogle Scholar
- 19.Binkley N, Harke J, Krueger D, Engelke J, Vallarta-Ast N, Gemar D, Checovich M, Chappell R, Suttie J (2009) Vitamin K treatment reduces undercarboxylated osteocalcin but does not alter bone turnover, density or geometry in healthy postmenopausal North American women. J Bone Miner Res 24:983–991CrossRefPubMedGoogle Scholar
- 20.Katsuyama H, Ideguchi S, Fukunaga M, Fukunaga T, Saijoh K, Sunami S (2004) Promotion of bone formation by fermented soybean (Natto) intake in premenopausal women. J Nutr Sci Vitaminol (Tokyo) 50:114–120Google Scholar
- 22.Kaneki M, Hedges SJ, Hosoi T, Fujiwara S, Lyons A, Crean SJ, Ishida N, Nakagawa M, Takechi M, Sano Y, Mizuno Y, Hoshino S, Miyao M, Inoue S, Horiki K, Shiraki M, Ouchi Y, Orimo H (2001) Japanese fermented soybean food as the major determinant of the large geographic difference in circulating levels of vitamin K2: possible implications for hip-fracture risk. Nutrition 17:315–321CrossRefPubMedGoogle Scholar
- 23.Katsuyama H, Ideguchi S, Fukunaga M, Saijoh K, Sunami S (2002) Usual dietary intake of fermented soybeans (Natto) is associated with bone mineral density in premenopausal women. J Nutr Sci Vitaminol (Tokyo) 48:207–215Google Scholar
- 37.Bischoff-Ferrari HA, wson-Hughes B, Baron JA, Burckhardt P, Li R, Spiegelman D, Specker B, Orav JE, Wong JB, Staehelin HB, O’Reilly E, Kiel DP, Willett WC (2007) Calcium intake and hip fracture risk in men and women: a meta-analysis of prospective cohort studies and randomized controlled trials. Am J Clin Nutr 86:1780–1790PubMedGoogle Scholar