NEW YORK - City health officials have battled trans fats and high-calorie fast food. Now, they're taking on salt.

The health department released draft guidelines recommending a maximum amount of salt that should be in a wide variety of manufactured and packaged foods, aiming to help reduce the average American's salt intake by 20 per cent in five years.

The recommendations, endorsed by 25 other city or state agencies and 17 national health organizations, call for sizable reductions in the sodium content of many products, from a 20 per cent drop in peanut butter to a 40 per cent decline in canned vegetables.

The guidelines suggest that manufacturers lower salt content gradually over several years so consumers won't notice, and they aren't asking for big changes in every category.

For example, under the city's standards, by 2014 no restaurant hamburger should contain more than 1,200 milligrams of salt. Nearly every burger sold by McDonald's already meets that guideline, although there are exceptions like the double quarter pounder with cheese, which has 1,380 milligrams of salt.

ConAgra Foods Inc., which makes products including Chef Boyardee canned pasta meals, Healthy Choice frozen dinners and Swiss Miss hot chocolate, has pledged to reduce the salt in its consumer food products by 20 per cent by 2015, in part because of consumer demand. It said its initiative would eliminate about 10 million pounds of salt per year from the American diet.

Still, processed-food companies have historically been extremely reluctant to tinker with recipes, especially when dealing with a key ingredient like salt, where even minor adjustments can affect taste. Salt also helps to preserve food and make bread rise.

And some of the changes the city is asking for are substantial. The target goals call for a 40 per cent reduction in the amount of salt in breakfast cereals, a 25 per cent reduction for breads and cold cuts and a 30 per cent cut for salad dressing.

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