February 12, 2007 — In a recent article in
Current Opinion in Clinical Nutrition and Metabolic Care, Sarah Booth,
PhD, lab director of the Vitamin K Laboratory at the Jean Mayer USDA
Human Nutrition Research Center on Aging at Tufts University (USDA
HNRCA), reviewed studies regarding vitamin K status among the elderly.
Although older adults seem to consume more vitamin K than younger
adults, many seniors are still not meeting the recommended intake of
"Research has shown poor vitamin K intake may be associated with
conditions such as bone fractures, bone loss, hardening of the
arteries, and osteoarthritis," says Booth, who is also a professor at
the Friedman School of Nutrition Science and Policy at Tufts.
Although it may be important for the elderly to increase dietary
vitamin K, Booth notes that it is also essential for researchers to
examine factors other than diet that may affect vitamin K status in the
body. "One promising area of research is the interrelationship between
estrogen and vitamin K," says Booth, "as studies indicate that low
estrogen levels in menopause may change the way vitamin K is
metabolized. More research is also needed to determine vitamin K status
of elderly men, as well as to determine what populations, if any, might
benefit from vitamin K supplements."
In a study published in Nutrition, Metabolism & Cardiovascular
Diseases, Booth and colleagues examined dietary patterns of more than
40,000 men to determine if phylloquinone, the form of vitamin K found
in plant sources like leafy green vegetables, could serve as a marker
for reduced risk of developing cardiovascular disease.
Booth and colleagues, including corresponding author Arja Erkkila,
PhD, of both the USDA HNRCA and the University of Kuopio in Finland,
determined that high phylloquinone intake did not appear to be an
independent risk factor for cardiovascular disease. However, men
consuming high amounts of phylloquinone generally had better dietary
habits, such as eating more fruits and vegetables and less saturated
fat. Men consuming high amounts of phylloquinone were also less likely
to smoke and more likely to exercise or take dietary supplements.
The association between high phylloquinone intake and a healthy diet
and lifestyle led Booth and colleagues to conclude that phylloquinone
intake could indeed play an important role in cardiovascular research
studies. "…In large population groups, phylloquinone may provide a
more robust assessment of overall cardiovascular risk status than
assessing multiple individual diet and lifestyle habits," write the
The Vitamin K Laboratory, as part of the Agricultural Research
Service (ARS) National Food and Nutrient Analysis Program, has been
contributing vitamin K food content data to the National Nutrient
Databank for nearly a decade. For more information on vitamin K
research at the USDA HNRCA, refer to "Tufts Researchers are Keeping
Track of Vitamin K" in the May/June 2006 issue of Friedman Nutrition
Notes [http://nutrition.tufts.edu/news/notes/2006-05.html]. The ARS is the chief scientific research agency of the USDA.
Booth, SL. Current Opinion in Clinical Nutrition & Metabolic
Care. 2007 (January);10(1):20-23. "Vitamin K Status in the Elderly."
Erkkila AT, Booth SL, Hu FB, Jacques PF, Lichtenstein AH. Nutrition,
Metabolism & Cardiovascular Diseases. 2007 (January);17(1):58-62.
"Phylloquinone intake and risk of cardiovascular diseases in men."
Source : Tufts University