Researchers who analyzed 114 studies on the effects of reducing salt in the diet say they found no evidence to support U.S. recommendations that even people with normal blood pressure limit their intake.
A salt-restricted diet can lower blood pressure in hypertensive patients older than 45, but has little or no benefit among younger patients and those with normal blood pressure, the majority of the population, previous research has suggested.
A study earlier this year even found that people on low-sodium diets died sooner than other people.
The latest analysis found that while salt reduction lowered blood pressure, it raised some blood chemicals _ including LDL or so-called "bad" cholesterol _ in potentially harmful ways, the authors reported in today's Journal of the American Medical Association.
"These results do not support a general recommendation to reduce sodium intake," said the authors, led by Dr. Niels Graudal of the University of Copenhagen in Denmark. His team analyzed 114 studies from 1966 through 1997.
An expert not involved in the work, Dr. Jeffrey Cutler of the National Heart, Lung and Blood Institute, said the analysis adds little knowledge about restricting sodium.
"If we think that it does any good, we're kind of stuck with making recommendations for everybody, unless we think it might do some harm," he said. "Even these authors say they can't conclude it causes harm, just things that might cause concern."
Dr. Alexander Logan, a professor of medicine at the University of Toronto, disagreed with Cutler and said the latest findings confirm others that support lifting the guidelines.
They recommend limiting sodium intake to no more than 2,400 milligrams a day, about the amount in a teaspoon of salt.