May 19, 2010 -- Government and industry efforts to cut the amount of salt in the American diet amount to a giant "national experiment" with no guarantee of success, one scientist is warning.
Most public health experts were ecstatic last month when the FDA announced it would embark on a decade-long program to gradually scale back the amount of salt in restaurant and packaged foods. Those foods contribute more than 70% of the salt consumed by Americans, who also have high rates of high blood pressure and cardiovascular disease.
The cuts are intended to put a dent in what most public health experts see as America's national sodium overdose. According to the CDC, Americans consume an average of 3,436 milligrams of sodium per day, though dietary guidelines for adults suggest limits of 2,300 milligrams daily as a general recommendation and less than 1,500 milligrams daily for individuals who are 40 years of age or older, African-American, or have a history of high blood pressure.
Sodium is known to increase blood pressure, and high blood pressure is a known risk factor for heart attacks, strokes, and other serious health problems.
But one expert is calling the program a leap of faith, likening it to "shooting first and asking questions later" in the fight to get Americans' blood pressure down.
"What we're involved in here is an experiment to see what's going to happen," says Michael Alderman, MD, chair of department of epidemiology at the Albert Einstein College of Medicine in New York.
Alderman acknowledges that sodium reductions lower blood pressure and that elevated blood pressure is related to cardiovascular disease. But controlled studies have failed to consistently show that cutting sodium actually cuts the risk of an early death or the risk of disease.
"We do not have evidence that reducing sodium is going to increase the quality or the duration of our lives," he said at a symposium on salt reductions sponsored by the American Society for Nutrition in Washington.
Other experts disagree. Many nutrition researchers and epidemiologists consider it a safe assumption: Americans' sodium intake is out of control, and gradually but substantially reducing the amount of salt in processed foods will save thousands of lives through population-wide reductions in blood pressure.
"We simply eat too much salt," said Sonia Angell, MD, director of the New York City Health Department's cardiovascular disease reduction program. In the wake of efforts to cut smoking, the city has embarked on a program to phase excess salt out of restaurant and packaged foods.
"We're at the point where we have the opportunity to save lives by reducing sodium," Angell says.
Alderman points to previous public health efforts that fell flat despite good intentions. Recommendations urging women to take hormone replacement therapy for menopause symptoms had to be rescinded after use by millions of women revealed an increased risk of breast cancer and other medical disorders.
"I think before we go on public health campaigns we need solid scientific evidence. Not hope, and not logic, but evidence," he says.
Still, efforts to gradually and steadily cut salt in packaged foods have won industry and government support and seem likely to proceed. The cuts are set to take place over 10 years.