| A Good Reason To Eat Your Veggies |
|
|
|
advertisement
|
By Lee Bowman
Scripps Howard News Service People with high blood levels of vitamin C have significantly reduced risk of stroke, according to a long-term study reported Thursday. The 20-year study involving more than 2,000 men and women in rural Japan, found that those with the lowest levels of vitamin C in their blood had a 70 percent higher risk of stroke than those with the highest levels of the vitamin. "To my knowledge, this is the first prospective study to make the correlation between vitamin C in the bloodstream and incidence of stroke,'' said Dr. Tetsuji Yokoyama, a research associate in epidemiology at the Medical Research Institute of Tokyo Medical and Dental University. He was lead author of the report in the October issue of Stroke, a journal of the American Heart Association. "The risk of stroke was inversely related to vitamin C in the bloodstream and frequency of vegetable consumption.'' Higher concentrations of vitamin C in the blood provided benefits even in patients with other risk factors, such as high blood pressure, heavier alcohol consumption, smoking or lower physical activity. However, those risk factors did diminish the benefits somewhat. While the reasons are unclear, it's known that smoking and alcohol may interfere with the absorption of vitamin C. The researchers examined strokes based on the number of days a week the participants ate fruits and vegetables. "The risk of all types of strokes was 58 percent lower among those who consumed vegetables six to seven days per week, compared to those who only consumed them up to two days a week,'' Yokoyama said. Although vitamin C levels also rise with vitamin C supplements, it was rare for people in the Japanese community to take vitamin pills when the study started in 1977, so the researchers could not measure what effect they might have. Over the course of two decades, there were 196 strokes among the subjects, 109 due to a blocked artery supplying the brain, and 54 caused by a burst artery in the brain. Another 33 were of an undetermined type. Since the risk of both types of stroke was reduced for those with high vitamin C levels, Yokoyama said the mechanism at work probably extends beyond vitamin C's known antioxidant effects. While that could explain why there's less build-up of fatty deposits in the arteries, it's unclear why the vitamins would protect against ruptured blood vessels. "One explanation may be that vitamin C may be a marker for higher intake of other nutrients which may protect against stroke,'' Yokoyama said. Whether vitamin C levels matter enough to warrant widespread screening of people for disease risk, the researchers can't yet tell. But they're preparing a new database on the same population looking at their experience with heart attacks. On the Net: www.armericanheart.org. (Lee Bowman covers health and science for Scripps Howard News Service. E-mail Lee at bowmanl@shns.com.)
| 
