High salt intake hikes stroke risk

From New Orleans, at a meeting of the American Stroke Association

People who consume a lot of salt are nearly twice as likely to experience a clot-based stroke as are people who consume a modest amount—even when their blood pressure readings are comparable, a study of New York City residents shows.

Armistead D. Williams, a physician at Columbia University Medical Center, and his colleagues asked 3,183 people to fill out questionnaires about their eating habits and lifestyles. The researchers then tracked the health of the respondents for more than 5 years.

Over that time, 142 of the people suffered strokes in which clots blocked blood flow to a part of the brain. People who consumed more than 4 grams of sodium per day had an 84 percent greater likelihood of having such a stroke than did people consuming 2.4 grams or less sodium daily, reports Williams. The American Heart Association recommends 2.4 grams as the upper daily limit for sodium intake. Most sodium is consumed in the form of salt.

The sodium connection to the higher stroke incidence held up even when the researchers accounted for other potential factors, among them blood pressure, age, ethnicity, diabetes status, and smoking history. Williams says that there is no ready explanation for why sodium itself, apart from its exacerbation of high blood pressure, could add to stroke risk. He acknowledged that the study didn’t examine whether borderline high blood pressure might have influenced the risk.

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