WASHINGTON, June 14 (UPI) -- The 2005 Dietary Guidelines issued by the U.S. Department of Health and Human Services should have remained silent on the issue of lowering sodium intake, experts said, because of a lack of evidence that suggests lowering salt leads to better health.
In a panel hosted by the Salt Institute, four medical researchers said there is insufficient evidence of the benefits of a low-sodium diet. They recommended that the government conduct more long-term studies before issuing any nutrition policy on salt.
The 2005 guidelines suggested Americans consume less than 2,300 milligrams of sodium per day to reduce the risk of elevated blood pressure. People with high blood pressure should consume less than 1,500 milligrams of sodium per day.
"We have no evidence that, for the entire population, 2,300 milligrams is, in fact, safe and efficacious in terms of doing what we expect it to do, which would be to reduce cardiovascular events," said Dr. David McCarron, a visiting professor at the University California, Davis.
McCarron suggested that improving the quality of a person's diet would make it unnecessary to modify salt intake to affect blood pressure and cited results of the "Dietary Approaches to Stop Hypertension" -- also known as DASHsodium -- study last year.
"The salt and hypertension policy that we have in hand has a very interesting history in that over the course of time the evidence has become weaker but the policy has become progressively stronger," said Dr. Suzanne Oparil, professor of medicine at the University of Alabama, Birmingham.
Kim Stitzel, a registered dietician and nutrition policy adviser at the Department of Health and Human Services, helped shape the dietary guidelines. She told United Press International the salt recommendations, made because of the effect salt has on blood pressure, were based the Institute of Medicine's Dietary Reference Intake.
"The higher one's consumption of salt, the higher one's blood pressure is," Stitzel said.
She said on average the basic consumption of salt per day for men was 4,300 milligrams and for women was 2,900 milligrams. She recommended people eat more fresh food and less sodium-rich food as a way to reduce salt intake, as well as increasing the intake of potassium in the diet.
"People are not eating enough fruits and vegetables and whole grains, and in lieu of those products they are eating foods that are high in saturated fats and sodium," she said.
Dr. Michael Alderman, professor of epidemiology and population at Einstein Medical College in New York, told the panel there was "no particular advantage to a low-sodium diet."
He said more studies are needed to show whether a low-sodium diet lowers the risk strokes, heart attacks and kidney failure.
There are no data showing reduced salt consumption improves quality of life, there is little evidence it improves multiple risk factors, and people may not be able to incorporate the 2005 recommendations into their lifestyle, McCarron said, adding if people added minerals and increased potassium in their diet it would be a much better way to decrease blood pressure.
Dr. Sandy Logan, professor of medicine at the University of Toronto, said studies are needed to show the net effect of dietary salt restrictions before public-health policy is crafted. Logan said Canada has taken a conservative approach, recommending that only salt-sensitive people should lower salt intake, instead of telling a whole population what to eat.
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Andrew Damstedt is an intern for UPI Science News. E-mail: [email protected]
