Researchers at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University suggest that low levels of circulating vitamin K are linked to increased risk of mobility limitation and disability in older adults. This means they are identifying a new factor to consider for maintaining mobility and independence in older age.

The study, published recently in the Journal of Gerontology: Medical Sciences, evaluates the association between biomarkers of vitamin K status and the onset of mobility limitation and disability in older adults.

“Because of our growing population of older people, it’s important for us to understand the variety of risk factors for mobility disability,” says Kyla Shea, first and corresponding author and a nutrition scientist in the Vitamin K Laboratory at the Jean Mayer USDA Human Nutrition Research Center on Aging (HNRCA) at Tufts University.

The new study examined two biomarkers: circulating levels of vitamin K (phylloquinone) and a functional measure of vitamin K (plasma ucMGP). Using participant data from the Health, Aging, and Body Composition Study (Health ABC), the study found that older adults with low levels of circulating vitamin K were more likely to develop mobility limitation and disability. The other biomarker, plasma ucMGP, did not show clear associations with mobility limitation and disability.

Specifically, older adults with low circulating vitamin K levels were nearly 1.5 times more likely to develop mobility limitation and nearly twice as likely to develop mobility disability compared to those with sufficient levels. This was true for both men and women, the release explains.

The study used data from 635 men and 688 women ages 70-79 years old, approximately 40 percent of whom were black, who participated in Health ABC. In Health ABC, mobility was assessed every six months for six to ten years through annual clinic visits and phone interviews in the intervening time.