HEALTHSCIENCE -- January 31, 2011 at 3:55 PM ET
New Government Guidelines on Salt Intake: Are They Achievable?
Federal guidelines on what Americans should -- and should not -- be eating were released on Monday.
Among them: reduce daily salt intake to less than 2,300 milligrams; less than 1,500 mg if you're 51 and older, according the U.S. Department of Agriculture.
Easy, right? Avoid fast food, French fries and potato chips, and you're halfway there. Not so fast. Even items pegged as healthy can be loaded with salt.
Consider this: One large bowl of chicken noodle soup at Cosi has 1,227 milligrams of salt, more than half the daily recommended allowance, and Cosi's country ham and brie sandwich alone packs 2,251 milligrams. Subway's six-inch Buffalo Chicken Sub has 1,290 milligrams of sodium. And an Asian chicken wrap at Schlotzy's Deli: 2,143 milligrams.
Sit-down restaurants can be even worse, said Marion Nestle, professor of nutrition, food studies and public health at New York University. "Chefs are notoriously used to cooking with a lot of salt."
More than 80 percent of sodium in the average American diet comes from processed foods. And the saltiest foods are often those you'd least expect: bread, cheese, rice, potatoes, even vegetables with salt or sauce added to cut the bitterness. "Sodium is a miraculously effective inhibitor of bitterness, and many vegetables served have salt in them," said Gary Beauchamp, director of the Monell Chemical Senses Center.
Reaction to the guidelines has been mixed. The Salt Institute called them "drastic," "simple" and "baseless." Obesity, it said, is a greater contributor to hypertension and salt an essential nutrient. The American Heart Association, on the other hand, said today they don't go far enough. All Americans, the agency said, should limit sodium intake to less than 1,500 milligrams a day.
But achieving lower sodium levels is challenging, even if you choose your foods carefully and buy groceries at health food stores, said Robert Rubin, a clinical professor of medicine at Georgetown University and author of a recent Institute of Medicine Report on sodium intake. "A lot of processed foods, we've grown accustomed to tasting a particular way. So it's very difficult to go cold turkey in terms of getting down to these lower levels."
Research has shown that it is possible to wean people incrementally off of high-salt diets. Scientists are also working to find sodium-free salt enhancers that can maintain saltiness without compromising health.
Still, reaching the 1,500 milligram cutoff is difficult, Beauchamp said. "It's possible for some people, but whether it's possible for the population as a whole, I don't know. But it's certainly something we should strive for."
Replacing highly processed, highly salted foods is especially tricky for low-income populations. "They don't have access to the kinds of foods we hope would be consumed instead of highly-salted foods," he said. "And, of course, they're more expensive. So there are two things together conspiring against them."
Most doctors believe that persistently high levels of sodium can lead to high blood pressure levels, which contributes to hypertension, stroke and heart disease.
The federal guidelines on salt haven't changed since 2005, but the latest report, which also urges Americans to eat less, drink more, consume more fruits and vegetables and less saturated fat, explains the recommendations more clearly than in the past, Nestle said. "I think they're the best ones that have ever come out." She especially likes that they start out by saying, "Enjoy your food."
But Nestle has a bone to pick. "They still use euphemisms," she said. "What they say is, 'limit the consumption of foods that contain refined grains, especially refined grain foods that contain solid fats, added sugars and sodium.' But what is that supposed to mean? What they're not saying is, 'Eat less meat, eat less junk food, eat fewer salty snacks and drink fewer sugar sodas. Why not just say that?"
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