The blame can be placed at the door of America's drug regulator, the Food and Drug Administration (FDA) which has decreed that salt is "generally recognised as safe".
Their position, say researchers, is out of step with similar bodies in the UK, Ireland, Finland and Australia, which have all set national targets for lowering salt intake, and have encouraged food manufacturers to comply with voluntary regulations.
If the FDA followed suit, manufacturers would have to get approval before adding salt to food, and the FDA would also have to set agreed limits.
Researchers reckon that around 150,000 lives could be saved every year in America if the nation halved its salt intake.
(Source: Journal of the American Medical Association, 2007; 298: 1439-41).