In the largest study of its kind, scientists looked at what happened when volunteers ate three levels of sodium: a "high" level typical of that eaten daily by most Americans; an "intermediate" level similar to the maximum recommended intake; and a "low" level roughly half of the "intermediate" level.
Consuming high amounts of sodium has been shown to increase risk for high blood pressure. Table salt (sodium chloride) is about 40 percent sodium.
The study reported today examined lipid data acquired during the Dietary Approaches to Stop Hypertension (DASH)-Sodium Trial, which was conducted at four U.S. medical centers between September 1997 and November 1999. The National Heart, Lung and Blood Institute sponsored the study.
"The main goal of the DASH-Sodium Trial was to test the effects of sodium intake on blood pressure in two distinct diets," said lead author Lawrence J. Appel, M.D., professor of medicine at the Johns Hopkins University School of Medicine in Baltimore.
The DASH diet emphasizes eating fruits, vegetables and low-fat dairy products and reduced amounts of red meat, fats and cholesterol. It is widely recommended to help people prevent or reduce high blood pressure and to lower the risk of heart disease. The study team reported in early 2001 that the DASH diet together with low sodium intake reduced blood pressure substantially.
Several small studies had previously suggested that extreme reductions in sodium would increase a person's lipid levels and thus, increase the risk of a heart attack or stroke.
"The DASH-Sodium trial also provided an unusual opportunity to examine the effects of sodium intake on lipids," Appel said. "We had a
Contact: Carole Bullock
American Heart Association