While salt contains essential nutrients that help the body regulate blood pressure and promote healthy muscle and nerve function, experts say each U.S. resident imbibes far too much of it – 9 to 12 grams (3,600 to 4,800 milligrams) a day. That’s 50 percent more than 40 years ago (and double the amount recommended by the U.S. government), and it comes mostly from eating processed foods and restaurant fare.
“Over time, we have adapted our taste buds and adapted our bodies to crave much, much higher levels of salt than we require to function,” said Kirsten Bibbins-Domingo, an epidemiologist at the University of California at San Francisco, who presented her study at an AHA conference.
In the investigation, led by Bibbins-Domingo, the researchers used a sophisticated computer model to map out how heart disease prevalence has changed over time among Americans. The team found that small nationwide reductions in salt consumption could dramatically improve public health. Decreasing salt by just 1 gram (or 400 mg of sodium) per person per day, the researchers estimated, could avert 30,000 cases of coronary heart disease in the United States by 2019. And lessening intake by half (up to 6 grams) could prevent 1.4 million cases of heart disease during that same decade.
The findings showed that the benefits of salt reduction would be greatest for blacks and women. Blacks tend to have higher blood pressure than other racial groups, and “many studies suggest that they may be more sensitive to salt,” Bibbins-Domingo said. She found that, while a reduction of 3 grams of salt a day for all Americans would lower heart attacks by an average of 8 percent, blacks would see a 10 percent decline. In women, stroke risk was foreseen to drop 8 percent with a 3-gram reduction in salt intake, while in men it was expected to fall 5 percent.