Magnesium-rich foods ward off stroke in smokers

CHICAGO (Reuters) - Diets rich magnesium, found in whole grains and vegetables, could help reduce stroke risk in smokers, researchers reported on Monday.

Their study of 26,000 male smokers in Finland found that those whose diets were high in magnesium had a significantly lower risk of one type of stroke.

While the mechanism is not clear, it may be that magnesium helps reduce high blood pressure, which can lead to stroke if untreated.

Susanna Larsson and colleagues at the Karolinska Institute in Stockholm, Sweden, said the stroke finding was an offshoot of a study whose main purpose was to look at possible lung cancer therapies.

Cigarette smoking is strongly linked to stroke and it is the leading cause of heart disease and cancer.

The study of 26,556 Finnish men followed for more than 13 years found that those who consumed an average of 589 milligrams of magnesium each day in their diets had a 15 percent lower risk for cerebral infarction -- a stroke that occurs when blood flow to the brain is blocked -- than those who consumed less magnesium.

The effect was stronger for men younger than 60 and the study also found that calcium, potassium and sodium intake were not associated with risk for any type of stroke, the researchers reported in the Archives of Internal Medicine.

They said it remains to be seen if taking magnesium dietary supplements would produce the same result.

"In addition to lowering blood pressure, magnesium may influence cholesterol concentrations or the body's use of insulin to turn glucose into energy. Either of these mechanisms would affect the risk for cerebral infarction but not hemorrhage (the cause of other types of strokes)," Larsson's team wrote.

Besides whole grains, foods high in magnesium are black beans, broccoli, halibut, peanuts, oysters, rockfish and spinach.

(Editing by Maggie Fox)