Bone health studies
Human studies linking consumption of MK-7 to improved bone health.
Bone is a living tissue comprised of a compact outer shell and an inner tissue matrix that is also mineralized, but has a sponge-like appearence. The entire skeleton is constantly being repaired and rebuilt so that it is more or less completely replaced approximately every seven years. This process is regulated by soluble factors and performed by cells (osteoblasts, cells that build up bone tissue, and osteoclasts, cells that break it down). Osteoblasts produce the vitamin K-dependent protein osteocalcin. This protein binds calcium to the bone matrix and builds healthy bones. As long as the bone-forming activity (formation) is equal to the bone-breakdown (resorption), the process of maintaining healthy bones is kept under control.
Osteocalcin is a vitamin K-dependent protein, which means it needs natural Vitamin K2 to function properly. Thus long-term vitamin K-deficiency may lead to loss of calcium in the bone and reduced quality of bone. Populations that consume a significant amount of natural Vitamin K2 have stronger, healthier bones. Unfortunately, the Western diet does not contain sufficient amounts of Vitamin K2 to achieve this, and the majority of healthy people are therefore Vitamin K2 deficient.
Compared to people from Japan and Singapore, people in Scandinavia, the US and the UK, have very different incidences of fractures in forearms or hips, with Oslo having the highest incidence. This is the case despite the fact that that Norwegians traditionally drink a lot of milk, one of the best dietary sources of calcium. Even if the differences are most obvious in women, statistics show that poor bone status is also common for men, and that men in the Far East have better bone health than men in the West.
Many studies with vitamin K have linked vitamin K consumption to bone health. Some of them are:
- Braam et al. (2003) and Knapen (2007)
- vitamin K supplementation helps promote bone health and preserve bone mineral density
- Kaneki et al. (2001) and Ikeda (2006)
- increased intake of MK-7 from natto resulted in better levels of activated osteocalcin and a reduced risk of hip fracture
- Yaegashi (2008)
- both calcium, magnesium, zinc and vitamin D were shown to be important for bone health, but natural Vitamin K2 from natto was identified as the key ingredient for preserving bone health.
Calcium, Vitamin D and Vitamin K2 in relation to bone health
Calcium has been the most obvious choice in bone health dietary supplements for decades. The major part of calcium (99%) in our bodies is in our skeleton (and teeth), only about 1% is found in the circulation. Calcium is involved in many important biochemical processes in the body, but the maintenance of the skeleton involves relatively large quantities of calcium. We need a steady supply of calcium to keep up the constant repair and rebuilding of the skeleton. However, we also require that the body can optimize the use of calcium. Several studies show that supplementing with calcium is not enough for optimal bone health. Adding vitamin D and vitamin K significantly improves bone health. Vitamin D stimulates the synthesis of osteocalcin, whereas Vitamin K2 is needed for the activation of osteocalcin. Only the Vitamin K2 activated osteocalcin will bind calcium optimally. In this way both vitamin D and Vitamin K2 work in synergy to enable efficient calcium use for improved bone health.