CHICAGO (AP) - Women who eat lots of whole-grain foods can significantly reduce their risk of strokes, researchers say in another study suggesting that healthy eating leads to healthy living.

Those who ate the most whole grains - the equivalent of two to three slices of whole-grain bread daily - were 30 percent to 40 percent less likely to have an ischemic stroke than women who ate less than half a slice or the equivalent daily.

The findings, based on data on 75,521 American participants in Harvard University's Nurses Health Study, appear in Wednesday's Journal of the American Medical Association.

From 1984 to 1996, 352 strokes occurred in the study group. Most were ischemic strokes, caused by blockages in arteries that feed the brain. Most of the estimated 600,000 strokes reported each year in the United States are of this type.

Strokes, America's third leading cause of death, afflict men and women equally but are more likely to be fatal in women.

In the study, the more whole grains women ate, the less likely they were to have a stroke.

The findings suggest that "replacing refined grains with whole grains by even one serving a day may have significant benefits in reducing the risk of ischemic stroke," wrote the authors, led by Dr. Simin Liu of Harvard's Brigham and Women's Hospital in Boston.

Whole grains consumed by study participants included whole-wheat bread, whole-grain cereal, popcorn, wheat germ, oatmeal, bulgur and couscous. Refined-grain foods included sweet rolls, white bread, white rice and English muffins.

Liu said it is unclear exactly how whole grains might prevent strokes, although they have been linked to lower levels of the so-called bad cholesterol that can clog arteries.

His study sought to determine if components of whole grains such as vitamin E and fiber might be responsible. But he found a risk reduction independent of those factors, suggesting that other mechanisms are at work.

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