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Nutritionists Kyla Shea (left) and Sarah Booth perform a DXA scan on a volunteer to measure bone mineral density as part of the vitamin K supplement study. Click the image for more information about it.

Vitamin K expert honored   Bone mineral benefits of vitamin K   Consumer-friendly nutrient listings

Tracking Vitamin K for Health

By Rosalie Marion Bliss
August 1, 2007

Could getting enough dietary vitamin K help keep osteoarthritis at bay? Study volunteers with the highest blood levels of the main form of vitamin K—phylloquinone—were associated with the lowest risk among participants of having osteoarthritis in the hands and knees. The study was conducted by Agricultural Research Service (ARS)-funded scientists.

Osteoarthritis is a joint disease that involves the breakdown of cartilage and bones, which leads to pain and stiffness.

The lead researcher, Sarah L. Booth, is director of the Vitamin K Laboratory at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University in Boston, Mass. She and Boston University rheumatologist Tuhina Neogi reported the findings in Arthritis & Rheumatism. ARS is the U.S. Department of Agriculture's chief scientific research agency.

For the study, Booth and colleagues used new methods to assess participants' vitamin K blood plasma concentrations, as well as associations between that status and osteoarthritis. The study is particularly significant because low dietary intakes of vitamin K are known to be associated with relatively higher amounts of bone loss in the elderly, according to authors.

The researchers have also determined the amount of several major types of vitamin K in hundreds of foods. Through a collaboration, those data and more are available via the ARS Nutrient Data Laboratory website, which is part of the Beltsville Human Nutrition Research Center at Beltsville, Md.

Dieticians and consumers, for example, can look up the vitamin K content in close to a thousand foods, using one of two listing choices. To access the Vitamin K Nutrient List, go to: http://www.ars.usda.gov/nutrientdata.

At left, choose "Products and Services" and then click on "Reports by Single Nutrients." From there, scroll down to "Vitamin K" under the nutrient column and then make a listing choice—either sorted alphabetically or sorted by nutrient quantity.

Read more about the research in the August 2007 issue of Agricultural Research magazine.