(AP) -- First, it was a ban on artery-clogging trans fats. Then calories were posted on menus. Now the New York City health department is taking on salt. City officials are meeting with food makers and restaurants to discuss reducing the amount of salt in common foods such as soup, pasta sauce, salad dressing and bread.
About three-quarters of the salt Americans eat comes from prepared and processed food, not from the salt shaker. That's why New York officials want the food industry to help cut back.
"It's very hard for an individual to do this on their own," said Dr. Lynn Silver, an assistant commissioner in the health department.
The department has shown its clout with bans on artificial trans fats and rules forcing chain restaurants to post calorie counts. To comply, fast food chains changed their recipes nationwide, and other cities and states have enacted similar policies.
Some manufacturers said getting rid of trans fats took work, and reducing salt has its own difficulties.
Unlike sugar, there's no substitute for salt. Cream soups - like that casserole favorite cream of mushroom - are the biggest challenge, said George Dowdie, head of research and development for Campbell Soup Co. The soup maker, which has been cutting salt for years, is in the talks with New York.
By fall, Campbell Soup plans to have more than 90 lower-sodium soups available. That includes its first soup, tomato, which will have almost a third less salt.
The industry hopes salt reduction remains voluntary.
"Literally freight cars full of salt have been removed from these products gradually over time," said Robert Earl, vice president of science policy, nutrition and health for the Grocery Manufacturers Association. "It has to be done carefully - gradually and incremental over time."
Herbert Smith Jr. never paid much attention to how much salt was in food until he developed high blood pressure. His doctor at a Harlem health center put him on medication and told him to exercise and watch his diet.
The 54-year-old church receptionist said he was alarmed to see how much salt was in the instant soup packages that he liked. He wants the food industry to cut down.
"For those who want to use salt, they can add it themselves," he said.
Too much salt raises blood pressure, and high blood pressure raises the risk of heart disease. A recent analysis showed that for every gram of salt cut, as many as 250,000 cases of heart disease and 200,000 deaths could be prevented over a decade.
"Very, very small changes in diet could have dramatic effects," said Dr. Kirsten Bibbins-Domingo, a researcher with the University of California, San Francisco.
For its salt initiative, New York has recruited public health agencies and medical groups across the country. The campaign - with a goal of cutting salt intake by at least 20 percent in five years - is modeled on a plan carried out in Britain. That effort set voluntary salt reduction targets for 85 categories of processed foods.
"Companies have been very innovative," said Corinne Vaughan, of Britain's Food Standards Agency. "And they have been very good at making what are quite huge reductions in salt levels."
Salt in pasta sauces has been cut by nearly a third, and soups by about one-quarter, she said. Some foods have been more challenging, she said, citing bacon, cheeses and packaged bread. With less salt, the dough is sticky and harder to process, she said. Salt is used mostly for flavoring but can also help preserve some foods and gives others texture.
Some British companies have also put "traffic light" labels on package fronts - green for low-salt, for example - so shoppers can "make a choice at a glance," Vaughan said.
Everyone needs some salt - or sodium chloride - for good health. The daily recommended amount for Americans is about a teaspoon, or 2,300 milligrams of sodium. But many people consume twice that amount. A Big Mac alone has 1,040 milligrams.
A recent government report showed that seven out of 10 adults should be eating even less than the recommended amount - about 1,500 milligrams. That includes anyone with high blood pressure, everyone over 40, and African-Americans, who are at greater risk than whites for high blood pressure.
The prospect of government intervention bothers some, and some critics note that not everyone is sensitive to salt. A few others contend there is not enough scientific evidence that reducing salt really drives down heart problems or deaths.
But many in the medical and public health field are firmly behind the idea.
"When you've got groups ... all saying we need to reduce salt, the evidence is exceedingly strong, you don't do more trials," said Dr. Stephen Havas, an adjunct professor at Northwestern University's medical school and a former American Medical Association vice president.
In the meantime, the Food and Drug Administration is considering a request that the government regulate salt content. An Institute of Medicine committee is also looking at ways to reduce salt consumption. The FDA says it is waiting for that committee report, due next year, before deciding the regulation issue.
Bibbins-Domingo, the University of California researcher, and her colleagues say their findings support efforts to lower salt levels, either voluntarily or through regulation.
She said her patients with high blood pressure struggle to cut down on salt. They give up potato chips, french fries and salty nuts, but end up eating processed foods like soups and pasta that can also have a lot of salt, she said.
"I realized how hard it is for patients who want to make those changes," she said.
New York resident Kristle Thompkins, 37, has been trying to make those changes herself.
She started reading labels and limiting salt a few years ago because of her high blood pressure. Now she's adjusted to eating less salt - although she still misses potato chips.
The macaroni and cheese she made for an Easter gathering now tastes "too salty."
"My salt tolerance has lowered," Thompkins said.
On the Net:
New York City Department of Health: http://www.nyc.gov/health
British salt program: http://www.salt.gov.uk
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