At a Manhattan grocery store, shoppers said they hadn't noticed the salt falloff, either because they didn't taste the difference or because they eschew prepared foods to begin with.

"A decrease is good â¿¿ not putting anything in there is even better. People should add their own salt," shopper Lynne Davis said.

Fashion design student Vanndy Pan said she doesn't think about the salt in her food, though her mother has high blood pressure.

"Maybe I should," the 26-year-old said as she bought a loaf of sandwich bread, but "I'm a student. At this point, I only buy the cheap food."

Health officials say Americans get the vast majority of their salt from processed and prepared foods, and not necessarily the foods they'd imagine: Bread and rolls are the No. 1 source.

"The problem is not the salt on the table. The problem is the salt on the label," city Health Commissioner Dr. Thomas Farley said.

The amount of salt in any given food item can vary widely. A slice of white bread can have 80 to 230 milligrams of sodium, for example. A cup of canned chicken noodle soup has 100 to 940 milligrams. A 1-ounce bag of potato chips ranges from 50 to 200 milligrams.

In one of a series of healthy-eating initiatives on Bloomberg's 11-year watch, the city announced voluntary salt guidelines in 2010 for various restaurant and store-bought foods. Besides trimming salt levels in the foods by 25 percent by 2014, the campaign aimed to reduce consumers' overall sodium intake by 20 percent in the same timeframe. Interim targets for the foods were set for 2012.

For instant hot cereals, as an example, the guidelines called for a 15 percent salt reduction by last year and a 31 percent cut by 2014.

A company can hit the target for a category, such as canned soup, even if not every product makes the mark.

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