Cutting ‘Hidden’ Salt Could Lower Blood Pressure

Many people think twice before adding a dash of salt to their food, but don’t realize that the majority of dietary sodium comes from packaged foods and eating out, according to a new study.

Reducing sodium intake to recommended levels could result in 11.1 million fewer cases of high blood pressure each year and reduce health care costs by as much as $18 billion as an added benefit, say researchers led by Kartika Palar, a doctoral fellow at Pardee RAND Graduate School.

In the United States, the maximum daily sodium recommendation is 2,300 milligrams but the average person consumes 3,400 milligrams per day, according to the study.
The authors simulated models of different sodium-reduction scenarios, pulling from population-level data on sodium intake, blood pressure and medication use from the National Health and Nutrition Examination Survey, conducted from 1999 to 2004.

The study appears in the September/October 2009 issue of the American Journal of Health Promotion.

Jasminka Ilich, Ph.D., a professor at Florida State University, is not affiliated with the study. Since the surveys were done several years ago, she said, “It is possible that the actual intake of sodium in the population has changed due to already huge public education and efforts to reduce sodium [therefore] rendering lower dollar savings than calculated in this study.”

Ilich agrees with the authors that bringing sodium intake to down to recommended levels would be a major undertaking.

“Sodium is present in all foods, but most abundantly in processed foods. On average, individuals get over 70 percent of their sodium from processed foods. Therefore, there isn’t much leverage in reducing table salt or added salt during cooking,” Ilich said.
“Policy interventions that target processed and restaurant foods, which account for the majority of average sodium intake in the U.S. — not salt added at the table — may be especially promising,” Palar said.

Ilich said the most efficient approach would be to educate the public about reading labels and about substituting or avoiding foods with high sodium content.
She said there is controversy about whether all people with hypertension would see improvement with sodium reduction. “There is another school of thought, according to which only sodium-sensitive people, about 6 percent of the adult population, can lower their blood pressure by reducing sodium intake.” Ilich said.