Literatus: K2, not yet for ‘bone loss’-A A +A
Tuesday, July 8, 2014
“IT'S only after we’ve lost everything that we’re free to do anything,” wrote Chuck Palahniuk in Fight Club. But such wisdom will not apply to bone loss. Freedom will be badly hampered in osteoporosis when bones start breaking. Neither can vitamin K, or more specifically vitamin K2, do more about this just yet.
The supposed bone-building effect of vitamin K has gained promotional mileage in recent years. In fact in Japan, according to the Asakura study in 2001 (Osteoporosis International), one of the most frequently prescribed treatments for osteoporosis is vitamin K2. Educational institutions in the United States, such as the University of Maryland Medical Center and the Linus Pauling Institute at Oregon State University also conferred with this beneficial effect of the vitamin against bone loss.
While theoretical knowledge (e.g. finding osteocalcin, matrix Gla protein, and protein S in bone) seems to support the contention, human clinical trials proved unsupportive so far.
By the way, osteocalcin, a protein, needs vitamin K in order to synthesize osteoblasts (bone-forming cells). Its function, however, remains unclear; although experts believe it has to do with bone mineralization.
Matrix Gla protein, on the other hand, has been found in bone, cartilage and soft tissue, including blood vessels. Its role in bone metabolism is unclear; although it seems to prevent calcification (hardening) of soft tissue and cartilage.
Anticoagulant protein S, another vitamin K-dependent protein, also synthesizes osteoblasts. But its role in bone metabolism is also unclear.
A most recent review of previous studies on the subject, the Hamidi and Cheung study published on June 23 in Molecular Nutritional Food Research, noted that the claims of bone-building from vitamin K had been based on small population size and their results too small to be significant.
For example, human studies done before the 2005 review found only less than one percent increase in bone mineral density with variation range about double it.
The researchers covered studies on osteoporosis of bone loss in postmenopausal women, Parkinson’s disease, anorexia, biliary cirrhosis, and stroke as well as bone loss from leuprolide drugs and prednisolone. Nutritionists Steven Plaza and David Lamson reported these in the Alternative Medicine Review.
John Steinbeck noted in The Winter of Our Discontent the difference between losing bones and not having it in the first place: “It’s so much darker when a light goes out than it would have been if it had never shown.” So treasure and protect your bones, while you still have it strong.
Published in the Sun.Star Cebu newspaper on July 09, 2014.