Many people often think of vitamin K for its roles in osteoporosis and cardiovascular health; however, it plays essential roles in many other aspects of health. In a study published last month in the Journal of Gerontology, researchers investigated the role of vitamin K in mobility and disability in the aging.

This is the first study to evaluate the association between vitamin K status and the onset of decreased mobility and disability in older adults. With our elderly population growing, it is estimated by next year that the 4^th leading cause of disability will be osteoarthritis. So, now more than ever, it is essential to determine risk factors associated with reduced mobility.

This new study included data from 635 men and 688 women ages 70 to 79 years of age who participated in the Health, Aging, and Body Composition Study. Mobility was assessed every six months over a six to ten-year period. The research team defined mobility limitation as two consecutive semi-annual reports of having any difficulty with either walking a ¼ mile or walking up 10 steps without resting. Furthermore, mobility disability was defined as having two consecutive semi-annual reports having a great deal of difficulty or an inability to walk or climb the same distance.

This study examined two biomarkers to assess vitamin K status: circulating levels of vitamin K1 (phylloquinone) and a functional marker of vitamin K (plasma ucMGP). As a result, the research team found that older adults with low levels of circulating vitamin K were more likely to develop mobility limitation and disability, while plasma ucMGP did not show a clear association with mobility limitation or disability. 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.

Circulating vitamin K levels reflect the amount of vitamin K in the diet. The best food sources of vitamin K include leafy greens such as kale, collards and spinach, and additional supplementation should be considered for those individuals who may benefit from higher amounts of vitamin K. It is important to maintain optimal levels of all the fat soluble vitamins, as more and more research demonstrates their intricate interrelationships with other nutrients such as calcium and magnesium. It is also important to note that there is no toxicity of vitamin K.

By Michael Jurgelewicz, DC, DACBN, DCBCN, CNS

Source: Shea MK, Kritchevsky SB, et al. Vitamin K status and mobility limitation and disability in older adults: The Health, Aging, and Body Composition Study. J Gerontol A Biol Sci Med Sci. 2019 May 6.