Sodium and Stroke

The United States Department of Agriculture recommends that Americans limit their sodium intake to less than 2400 milligrams per day. The American Heart Association, however, recommends a limit of 1500 milligrams per day. We know that high levels of sodium in the diet are linked to high blood pressure and thus to the risk of stroke, but until recently many studies have not tried to link sodium and stroke more directly.

In a well-designed study recently published in the journal Stroke (2012;43(5):1200-1205), researchers at the University of Miami and Columbia University in New York City collaborated to use information gathered through a multiethnic study of diet and stroke based in Northern Manhattan. The over 2,600 participants in the researchers' analysis were between 50 and 80 years of age and had not previously experienced a stroke at the start of the ten-year study. Over half of the participants (53%) were Hispanic, while 21% were white and 24% black.

At the start of the study the participants answered a detailed dietary questionnaire to help determine their daily sodium intake. Every year thereafter the participants were recontacted to discuss their current health, including any hospitalizations, medication changes, or changes in stroke risk factors (such as smoking).

Interestingly, only 12% of the participants were meeting the American Heart Association recommendation of less than 1500 milligrams of sodium per day. Slightly more than one third of the participants were under the USDA recommendation of less than 2400 milligrams per day, while 21% were consuming over 4,000 milligrams of sodium per day.

The researchers then compared the sodium intake of those who experienced stroke of any kind or a heart attack with those who did not. They found that compared to those meeting the AHA recommendation, those who were consuming over 4,000 milligrams of sodium per day were more than 2 and a half times more likely to have a stroke. In fact, every increase of sodium intake of 500 milligrams per day increased the risk of stroke by 17%: an intake of 2500 milligrams per day meant a 34% increase in risk; 3,000 milligrams per day was a 51% increase in risk, and so on.

What this means for you

While the USDA recommends 2,400mg/day for most Americans, it further recommends that those over 50, black, or suffering from diabetes, high blood pressure or kidney disease limit their intake to 1500mg/day. This study certainly supports the American Heart Association's recommendation that all Americans reduce their intake to under 1500mg/day. You can get started reducing your sodium intake with our low sodium recipes, which are designed to keep your intake under the 2400 milligram per day target. Find the low sodium recipes on this website.

First posted: June 27, 2012