Only dairy that included vitamin K1 or K2 in the formula mix used during this study, enriched with calcium and vitamin D, led to changes in levels of osteocalcin. Without vitamin K1 or K2 however, only bone mineral density was enhanced.
Osteocalcin is a vitamin K dependent protein, and is essential for the body to utilise calcium in bone tissue. Without adequate vitamin K, osteocalcin remains inactive.
"The present study revealed more favorable changes in bone metabolism and bone mass indices for the twon vitamin K-supplemented groups, mainly reflected in the suppression of serum levels of bone remodeling indices and in the more positive changes in lumbar spine BMD for these two study groups," report researchers from Harokopio University in Greece.
There are two main forms of vitamin K- vitamin K1 (phytonadione), found in green leafy vegetables such as lettuce, spinach and broccoli; and vitamin K2 (menaquinones) which can be synthesised in the gut by microflora.
Deficiency in vitamin K has raised concerns amongst health professionals and has thus increased consumer awareness of the potential health benefits of vitamin K supplementation and sourcing through foods.
"What is really impressive is the growth in vitamin K supplementation, estimated to be (my personal estimate) over 15% year. We feel that the K2 market can double in less than five years," says Francis Foley from Xsto, the US distributor of Kappa's K2Vital Vitamin K product line.
The study resulted in significant increases bone mineral density in women consuming the vitamin K-enriched products, after 12 months of supplementation.
75 million affected
The results of the study show promise for the reduction of the risks associated with osteoporosis in postmenopausal women. Osteoporosis, which is characterised by low bone mass, can lead to increased risk of fractures in the hips, spine and wrists.
It is estimated that 75 million people suffer from osteoporosis in Europe, the USA and Japan. Outlining a need for further research in to the benefits of vitamin K supplementation in relation to boosting bone health.
Source: Calcified Tissue International
Study: "Changes in Parameters of Bone Metabolism in Postmenopausal Women Following a 12-month Intervention Period Using Dairy Products Enriched with Calcium, Vitamin D, and Phylloquinone (Vitamin K1) or Menaquinone-7 (Vitamin K2): The Postmenopausal Health Study"