September 21, 2009

Diet intake of vitamin K linked to aging

U.S. researchers suggest ensuring optimal dietary intakes of vitamin K can help prevent age-related conditions such as bone fragility and heart disease.

Children's Hospital Oakland Research Institute scientists said vitamin K is concentrated in dark green plants such as spinach or Swiss chard, and is either not present or present in only small amounts in most multivitamin pills.

Joyce McCann and Bruce Ames analyzed data from hundreds of published articles dating back to the 1970s designed to test Ames' triage theory that provides a new basis for determining the optimum intake of individual vitamins and minerals.

The analysis, which strongly supports Ames' theory, scheduled to be published in the October issue of the American Journal of Clinical Nutrition, supports recommendations by some experts that non-clotting functions requiring vitamin K may need higher intakes than are currently recommended.

Vitamin K is known as the Koagulation vitamin because about half of the 16 known proteins that depend on vitamin K are necessary for blood coagulation. The other vitamin K-dependent proteins are involved in a variety of different functions involving the skeletal, arterial, and immune systems, the researchers said.