Vitamin K2 supplements reduce bone loss in women

Friday, March 29, 2013. An article that appeared online on March 23, 2013 in the journal Osteoporosis International reports the outcome of a trial conducted by researchers in the Netherlands which found a benefit for supplementing with vitamin K2 in postmenopausal women—a group that has an increased risk of developing osteoporosis.

Two hundred forty-four women between the ages of 55 and 65 years were divided to receive 180 micrograms of menaquinone-7 (MK-7, a form of vitamin K2) or a placebo daily for three years. Lumbar spine, hip and femoral neck bone mineral density and bone mineral content, and vertebral fracture assessment were obtained by dual-energy X-ray absorptiometry (DXA) upon enrollment and yearly until the trial's conclusion. Femoral neck bone strength and vitamin K status as determined by the ratio of uncarboxylated to carboxylated osteocalcin were additionally assessed at these time points.

Women who received MK-7 had improved vitamin K status and a significant reduction in the decline of bone mineral content and bone mineral density of the femoral neck and lumbar spine in comparison with those who received a placebo. While women in the placebo group experienced the expected age-related decrease in bone mineral content and density in the lumbar spine, these values had decreased by less than 1 percent in those that received vitamin K in comparison with measurements obtained at the beginning of the study. Participants who received vitamin K also had better bone strength and a reduction in the loss of vertebral height in the middle site of the lower thoracic region after two and three years of supplementation.

"Long-term use of MK-7 supplements significantly decreased the age-related decline in bone mass and strength," authors M. H. J. Knapen and colleagues write. "We conclude therefore that postmenopausal women may benefit from taking MK-7 supplements to prevent the age-related bone loss."