For years, Americans have heard the lecture: Consume less sodium, or face an increased risk of high blood pressure, heart attack and stroke.
Some people have taken heed. They know to be wary of salt in the usual suspects, such as hot dogs, lunchmeat, many canned foods and fast food. But a recent government study shows we had better watch out for bread, too.
Say what?
Bread is the No. 1 source of sodium in Americans' diets. People get twice as much from bread and rolls as they do from snacks such as potato chips and pretzels, according to data from the Centers for Disease Control and Prevention. Consider that a typical 1-ounce slice of bread has between 100 and 200 milligrams, depending on the type and brand; an ounce of potato chips has roughly 120 or more.
Other top sources of sodium look as if they're right off the daily menu for lots of Americans: cold cuts and cured meats, pizza, poultry, soup, fast-food burgers, sandwiches, and cheese and pasta dishes.
Breads and rolls aren't saltier than many of the other foods, but they are consumed frequently by many people, says Mary Cogswell, a CDC researcher and one of the study's authors. "Bread is also one of the top sources of calories because we consume so much of it."
The data show that Americans are getting most of the sodium in their diets from processed and restaurant foods, not the salt shaker. People consume an average 3,266 milligrams of sodium a day, or about 1 teaspoons, excluding the salt added at the table, the CDC report shows.
Milligrams in the guidelines
The government's dietary guidelines advise reducing daily sodium intake to less than 2,300 milligrams for many people and knocking back to 1,500 milligrams for people 51 and older and those of any age who are African American or have hypertension, diabetes or chronic kidney disease.
In some people, sodium increases blood pressure because it holds excess fluid in the body, placing an added burden on the heart, the American Heart Association says. Too much sodium in the diet may also increase the risk for stroke, heart failure, osteoporosis, stomach cancer and kidney disease, the group says.
Some people, especially some African Americans and others who are genetically predisposed, are more salt-sensitive, says Linda Van Horn, a spokeswoman for the American Heart Association and a research dietitian with the Feinberg School of Medicine at Northwestern University. When they are exposed to sodium, they retain more fluid because of the way their kidneys handle sodium, and they may have a greater proportional rise in blood pressure.
Says Van Horn: "There is growing and compelling evidence that lowering dietary sodium lowers blood pressure not only in hypertensive people, but even in people with normal blood pressure levels. This reduces risk for heart attack and stroke."
But leaders of the salt industry say their product has been unjustly criticized.
"I cannot understand how our entire public health establishment can go on talking about salt and ignoring every single peer-reviewed publication that counters the salt-restriction agenda," says Morton Satin, vice president of science and research for the Salt Institute, an industry group.
"I always felt the whole salt-reduction agenda was just a sham from the very beginning," he says. "There's never been any scientific justification for the 2,300-milligram and 1,500-milligram recommendations."
Satin says people in other countries eat an average of 2,700 to 4,900 milligrams of sodium.
"The typical Mediterranean diet contains a lot more salt -- about 40% more salt -- than the typical American diet, but it's also much higher in salads and vegetables," he says. "You can't eat a salad or vegetables without adding salt. Anybody who eats a salad without salt might as well eat grass."
As the debate rages on, consumers who want to cut down on salt have their work cut out for them, especially if they eat processed foods, prepared foods or restaurant fare, including fast food. A pinch of salt here. A pinch there. It all adds up.
Varying degrees of salt
The amount of sodium in breads, rolls and biscuits varies by manufacturer, brand and type, says Dawn Jackson Blatner, a registered dietitian in Chicago. In general, a biscuit (2.5-inch diameter) has about 348 milligrams; a whole English muffin, 206 milligrams; 6-inch pita, 322 milligrams; a piece of cornbread, 428 milligrams.
Blatner's advice to consumers: Cut down, not out. "Aim to use smaller slices of bread and do tricks such as open-faced sandwiches."
Salt is crucial for making most breads, says Roger Clemens, a professor of pharmacology at the University of Southern California and a president of the Institute of Food Technologists.
Manufacturers use sodium chloride and sodium bicarbonate to give bread texture and get dough to rise, Clemens says. "These give dough improved structure and serve as a leavening agent. Salt gives bread spring. It ties the gluten together. And sodium chloride is a natural preservative."
Some manufacturers have experimented with low-sodium items, and in some cases, consumers have turned up their noses, he says. "If it doesn't taste good, consumers won't buy it."
In one study, researchers cut the sodium in bread in half, and people couldn't tell the difference, but when they cut it by two-thirds, people began to notice, says Bonnie Liebman, nutrition director for the Center for Science in the Public Interest.
Some food companies have cut back on sodium so that their bread has roughly 100 milligrams in a slice instead of about 200 milligrams, Liebman says. She advises consumers to look for those.
Watch that pizza, too
But just watching the salt in one food isn't enough, Liebman says. "We wouldn't want people to think that as long as they get a lower-sodium bread, they don't have to worry about high-sodium foods like pizza, Chinese foods, Italian food, bacon, hot dogs and lunchmeat."
Many restaurant foods are high in sodium, including big specialty hamburgers with 1,000 milligrams and personal pizzas with 2,500 milligrams, she says.
Liebman says what's tricky about sodium is that you can't always tell by the taste whether a food is loaded with salt.
"Foods that have salt on the surface, like potato chips, taste saltier than they are," she says. Some cereals have more salt in a serving than you'd get in a serving of chips, she says.
If sodium levels were reduced across the board in foods, people's preferences would shift downward so they would begin to like lower levels, says Gary Beauchamp, director of the Monell Chemical Senses Center in Philadelphia, a non-profit institute that researches taste and smell. "This might be particularly profound in young children."
The taste for salt is acquired and can be reversed to a lower level, Van Horn says. "If the food industry would collectively help lower the sodium, even a little, in processed foods, America's taste for salt could gradually be diminished."
In the meantime, read the labels on processed foods carefully and choose accordingly, she says. Remember that fresh produce, fish, poultry and meats are naturally low in sodium.
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