High-salt diets have been linked with an increase in blood pressure and a higher risk of heart disease and stroke.
Researchers thought they would find that salt intake had increased over time because Americans eat more processed foods today than the 1950s.
The study's main message in the American Journal of Clinical Nutrition: for all the intense effort to get Americans to limit salt intake, it hasn't happened.
Experts say cutting salt intake in processed foods by half could save 150,000 lives in the U.S. every year.
