WEDNESDAY, March 11 (HealthDay News) -- If Americans cut just one gram of salt from their daily diet, there would be 250,000 fewer new cases of heart disease and more than 200,000 fewer deaths over a decade, a new study suggests.
And, though doctors have long known that too much salt is linked with high blood pressure and heart disease, Americans are using 50 percent more salt than they did in the 1970s -- and blood pressure rates have risen by almost the same percentage, the study authors said.
"We found that very small reductions in salt intake would have very large health benefits in the U.S. population," said lead researcher Dr. Kirsten Bibbins-Domingo, an assistant professor of medicine and epidemiology at the University of California, San Francisco.
"We found that everyone in the U.S. would benefit, but the benefits would be particularly great for African-Americans, who are more likely to have high blood pressure and whose blood pressure is more likely to be sensitive to salt," she said.
Currently, Americans consume 9 grams to 12 grams of salt a day, with much of it coming from processed foods. This total is far more salt than is recommended by many health organizations, which say you should only have 5 grams to 6 grams a day, Bibbins-Domingo said.
Bibbins-Domingo was to present the findings Wednesday at the American Heart Association's Cardiovascular Disease Epidemiology and Prevention annual conference, in Palm Harbor, Fla.
For the study, the researchers used a computer simulation called the Coronary Heart Disease Policy Model to estimate the impact of reducing salt by 0 grams to 6 grams on heart disease and deaths from heart disease.
The model said that, between 2010 and 2019, there could be more than 800,000 "life years" saved for every gram of salt removed from the diet. If 6 grams a day were cut from people's diets, there would be 1.4 million fewer cases of heart disease and 1.1 million fewer deaths.
Just cutting salt intake by 3 grams a day would mean 6 percent fewer new cases of heart disease, 8 percent fewer heart attacks and 3 percent fewer deaths. These benefits would be even greater for blacks -- there would be 10 percent fewer new cases of heart disease, 13 percent fewer heart attacks and 6 percent fewer deaths, the study said.
"Reductions in salt are difficult for individuals to achieve, because most of the salt in the diet is from processed food, not from salt added to food at the table or while cooking," Bibbins-Domingo said. "Our results suggest that very small reductions in the salt in processed food -- reductions that would not be noticeable in the tastes of most foods -- could lead to the reductions in heart disease and deaths that we model here."
The food industry could take steps to voluntarily reduce salt in processed foods, as has been done in the United Kingdom, Bibbins-Domingo said. "Policy makers could also achieve these objectives through regulation. Such steps, in addition to efforts on the part of individuals to be mindful of their salt intake, could lead to improved heart health across the U.S."
Dr. Gregg C. Fonarow, a professor of cardiology at the University of California, Los Angeles, agreed that reducing salt in your diet could reduce your blood pressure, lowering your odds of developing heart disease.
"The findings of this study are highly dependent on a number of presumptions, some of which have not been tested in randomized clinical trials. Nevertheless, better control of blood pressure in the U.S. would be expected to result in large reductions in clinical events," he said.
The American Heart Association recommends that healthy adults eat less than 2.3 grams of sodium a day, Fonarow noted.
For more on salt, visit the American Heart Association.
SOURCES: Kirsten Bibbins-Domingo, Ph.D., M.D., assistant professor, medicine and epidemiology, University of California, San Francisco; Gregg C. Fonarow, M.D., professor, cardiology, University of California, Los Angeles; March 11, 2009, presentation, American Heart Association's Cardiovascular Disease Epidemiology and Prevention annual conference, Palm Harbor, Fla.