Data from the Framingham Heart Study 1996-2000 suggest that low vitamin K intake may contribute to lower bone mineral density (BMD) in women. Researchers measured the BMD of 2,591 men and women aged 29 to 86 and assessed dietary and supplemental vitamin K intake with a food-frequency questionnaire.

Vitamin K helps certain proteins bind calcium, which is required for proper bone mineralization. Women with the lowest vitamin K intakes had significantly lower mean BMD at the femoral neck and spine than did those with the highest intakes.

Recommended levels of 90 micrograms per day for women and 120 micrograms for men can be met by consuming adequate amounts of leafy green vegetables and vegetable-derived oils and spreads.

To locate good sources of vitamin K via the Internet, go to www.nal.usda.gov/fnic/foodcomp. There you will find a link to USDA's Standard Reference database, with instructions for searching by specific food.

Sarah L. Booth, Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston, Massachusetts; phone (617) 556-3231.

(Source: Agricultural Research magazine. 09/03)