Healthy postmenopausal women reduce their risk of stroke if their diet is rich in potassium, according to a research team led by Sylvia Wassertheil-Smoller, Ph.D., of Albert Einstein College of Medicine in the Bronx.

According to Dr. Wassertheil-Smoller, previous research has shown that potassium could lower blood pressure, but it was never clear as to whether it could ward off stroke.

"Our findings give women another reason to eat their fruits and vegetables," she says. "Fruits and vegetables are good sources of potassium, and potassium not only lowers postmenopausal women's risk of stroke, but also death."

Over the course of 11 years, researchers worked with 90,137 postmenopausal women between the ages of 50 to 79, observing their potassium intake and incidence of stroke.

At the start of the study, none of the participants had undergone a stroke and they averaged a daily potassium quotient from food of 2,611mg.

Those whose diets were among the richest in potassium reduced their general risk of stroke by 12 percent over those whose diets contained the least amount of potassium.

Participants whose blood pressure was in the normal range and who were not taking medications for hypertension reduced their general risk of stroke by 21 percent. On the other hand, for women with high blood pressure, including those taking medications for hypertension, a potassium rich diet did not lower risk of stroke, suggesting that a high potassium diet could be beneficial before the onset of high blood pressure.

"Our findings suggest that women need to eat more potassium-rich foods," says Dr. Wassertheil-Smoller. "You won't find high potassium in junk food. Some foods high in potassium include white and sweet potatoes, bananas and white beans."

Before piling these foods into the grocery cart in bulk, Dr. Wassertheil-Smoller suggests checking with one's doctor to assess potassium intake because too much of it can be dangerous to the heart.

Still, only 2.8 percent of women in Dr. Wassertheil-Smoller's study met the U.S. Department of Agriculture's recommended daily potassium intake of 4,700mg and only 16 percent of participants met the World Health Organization's daily potassium recommendation of 3,510mg.

The study did not take sodium consumption into account, and the balance between sodium and potassium is important. Further research, says Dr. Wassertheil-Smoller, should account for sodium and investigate the need for a potassium rich diet in younger people.

The study was published in the American Heart Association's journal Stroke.