Study: Lower salt intake could be riskier than thought
By Nanci Hellmich, USA TODAY
By Katye Martens, USA TODAY
A European study finds that those who ingest less sodium have an increased risk of cardiovascular death, but U.S. experts are taking the results with a grain of salt.
The American Heart Association encourages people to consume no more than 1,500 milligrams a day of sodium to reduce their risk of high blood pressure, heart attacks, stroke and kidney disease. This is less than half of what people consume now.
One reason for this advice: Elevated blood pressure is a major public health problem approximately 90% of all Americans will develop hypertension over their lifetime, the heart association says.
But a new European population study coordinated in Belgium raises questions about sodium and its effect on the heart.
Researchers followed 3,681 people, average age 40, for about eight years, testing sodium excretion in the urine. They found that systolic blood pressure (the top number) was slightly lower in those who excreted less sodium, but this didn't translate into a lower risk of cardiovascular death — in fact, those with lower sodium excretion had an increased risk of cardiovascular death. The findings were consistent in participants younger and older than 60 years.
Jan Staessen, a professor of medicine at the University of Leuven in Belgium and one of the authors of the study in Wednesday's Journal of the American Medical Association, says this study does not support the recommendation of a general reduction of salt intake for everyone, although salt reduction could be beneficial in lowering the blood pressure of people with hypertension. "Lower sodium intake is recommended for people with high blood pressure and people with heart failure, but recommending it to the population as a whole, I wouldn't do without proving it's completely safe," he says.
"If one lowers sodium intake to lower blood pressure, this change in sodium activates several systems (including the renin-angiotensin aldosterone system) that conserve sodium, and those systems are implicated in disease processes such as damaging the arterial wall and kidneys," Staessen says,
This study may apply to Americans of white European descent, but it might less applicable to blacks because they are believed to be more salt sensitive, he says.