

Salt Sense

Spare the salt, spare the heart

Salt Sense

We have long known that eating less salt lowers blood pressure, but a new study shows it also reduces the risk of heart disease. While people who are obese, have high blood pressure and are middle aged or older gain the most by reducing the amount of salt they eat (or drink), people who are not in those high risk groups can also benefit from reducing their salt consumption.

"What we have found is that sodium has an effect on the vasculature, even if you have normal blood pressure," says lead author Alanna Morrison, PhD, associate professor of public health at The University of Texas Health Science Center at Houston (UTHealth) School of Public Health, who co-authored the study with Roberta Ness, MD, MPH, dean of the School of Public Health. Their extensive review of studies on salt and the heart appears in the February online edition of the Annual Review of Public Health.

These pretzels are making me thirsty... and unhealthy.

Salt adds flavor to our food, and helps the body's nerves and muscles function, but eating too much of it puts unnecessary stress on the body, Morrison says. Salt makes the body retain water, which increases blood volume and raises blood pressure. You see the effects of eating too much salt after you eat a bag of chips or movie popcorn.

"When you step on the scale, you automatically gain five pounds," Morrison says. "That's water retention, and it puts a lot of pressure on the arteries on the body. It taxes the blood vessels and also makes the kidneys work harder, trying to balance the sodium/water levels in the body."

Salt Q&A

Add flavor without salt

Are you a saltaholic? Registered Dietitian, Carol Wolin-Riklin, and Bariatric Nutrition coordinator with The University of Texas Medical School at Houston, offers some suggestions on how to reduce the salt in your food while keeping the flavor.

What foods in particular contain a lot of salt?
High sodium foods include fast foods, chips, crackers, pretzels, pickles, relish, canned vegetables, processed meats (such as salami or bologna), canned soups, soy sauce, cheeses and frozen meals.

What spices or condiments can we use instead of salt to make our food tasty?
Spice blends such as Mrs. Dash can be used to add taste. Beware of spice blends that call themselves names other than garlic salt or onion salt, such as Lemon Pepper or Garlic Pepper. These seasonings may be high in sodium but have a misleading label. Always read the label and look for wording such as salt, sodium or monosodium glutamate (MSG). Those are the spices and seasoning blends that contain sodium and should be avoided on a low-sodium diet.

What about salt substitutes?
Items sold as salt substitutes or "lite" salt often have significant sodium content. The concern with the salt substitutes is the potassium content as the sodium in salt is often replaced with potassium. The potassium may impart a metallic taste in the substitute but a more troubling issue is the danger of excess potassium. The labels for salt substitutes carry a warning for those with cardiac disease, renal disease and diabetes. Increases in potassium may affect fluid regulation, cause nausea or diarrhea or cause muscle weakness and slow the heart rate. Potassium may also need to be restricted with certain drug regimens.

What should we use to flavor our foods instead?
Salt alternatives (spices and herbs) are always a better choice than salt substitutes. Find a local spice store or shop a spice store online. The list of spices that are very low in sodium or are sodium free is long and varied in flavors. Seasonings include cumin, onion powder, garlic powder, thyme, chili powder, curry. You can also search online for spice blend recipes or create your own based on personal preferences. Orange peel and lemon peel are often included in homemade recipes to add flavor and zest. Cook foods in fresh herbs—such as parsley, cilantro, basil and thyme—to help flavor foods without adding to the sodium content.

Do you recommend cutting out all salt cold turkey or doing it gradually so that one gets used to it?
Gradual changes are usually the changes that last longer as we are more likely to incorporate them into a lifestyle change. Finding an alternative to higher sodium seasonings takes time and may be a process of trial and error as we discover what herbs and spices please our taste buds without the sodium.

Morrison also found that increased salt intake was associated with cardiovascular disease.

But there's hope. Reducing the amount of salt you eat reduces blood pressure and puts less stress on the kidneys. Even a small reduction in blood pressure can make a big difference in the risk of developing heart disease, Morrison says. Because so many Americans have high blood pressure, that small reduction would have a big effect on the number of cases of people who develop complications from cardiovascular disease and people who die from it.

It is never too early to start cutting back on salt, Morrison says. Controlling blood pressure throughout life substantially reduces the risk of cardiovascular disease. One of the studies Morrison and Ness reviewed showed that infants on a low-sodium diet had lower blood pressure than the control group, who were fed a normal diet. The effects of their lower blood pressure persisted into adolescence.

But older adults benefitted the most from reducing sodium, lowering their risk of dying from stroke and cardiovascular disease.

How much salt is too much?

Dietary guidelines recommend that average, healthy adults consume less than 2,300 mg of salt a day, or about 1 teaspoon. Guidelines are stricter, less than 1,500 milligrams, for African-Americans, people with high blood pressure and middle-aged or older adults. Think you fit in the healthy category? Chances are, you don't. The Centers for Disease Control and Prevention estimates that nearly 70 percent of all Americans should be following the guidelines for 1,500 milligrams of salt a day. A recent advisory by the American Heart Association states that 1,500 milligrams of salt a day is appropriate for all Americans.

"Most Americans are consuming twice as much salt as they should," Morrison says. The average salt consumption for adults over age 20 is 3,000 to 3,600 milligrams a day.

Seek out hidden salt

Easing up on the salt shaker is a positive step, but salt contained in the food we choose to consume is the problem, Morrison says.

"It is a challenge to stay within the recommendations," she continues. "If you go through your refrigerator or your pantry, things like the cereal that you feed your children or pasta, foods that you think are healthy—they all have salt in them. As consumers we really can't get away from salt because it is in everything."

Nearly three-quarters of the salt Americans eat comes from processed foods. Morrison recommends looking at labels to determine salt content, and to avoid high-salt foods when possible. Even sweet-tasting foods and beverages likely have sodium in them. Eating mostly non-processed foods is a good way to reduce salt from your diet, Morrison says, because most natural foods, such as fruit, vegetables and lean meat, have little salt in them. Also, eliminating salt in food preparation can significantly reduce sodium intake.

Taste matters

Most people will balk at forced and immediate lowering of salt in food (see sidebar for tips on alternatives to salt), Morrison says, but research shows that taste for salt decreases after a period of cutting back.

"If you can start this early (reducing salt) even in children, you can reset your taste receptors. Then those children across their lifespan will be able to reduce their cardiovascular risk," Morrison says. "For older adults who are used to it, it might be more difficult, but if you get children now, they might not have that preset salt taste that we as older adults might have."

Gradual reduction of sodium intake by 1,176 milligrams a day could save 393,000 quality-adjusted life years and $38 billion in health care costs, according to a 2010 study published in the New England Journal of Medicine, cited in Morrison and Ness' paper.

Convinced of the importance of lowering salt in the American diet, the Institute of Medicine released a study in 2010 recommending that the Food and Drug Administration set mandatory government standards to reduce sodium content in foods over time. And U.S. cities, health organizations and even food manufacturers are getting the message. Following their trans fats initiative, the New York City Health Department has unveiled The National Salt Reduction Initiative (NSRI) to encourage incremental sodium reduction by food manufacturers and restaurant chains. Heinz, Hostess, Kraft Foods, Starbucks and other food giants have signed on to the initiative. The NSRI's goal is to reduce America's salt intake by 20 percent over five years—a positive step, Morrison says.

"I think the take home message is that everybody should be concerned (about salt consumption)," she says. "Even in low-risk groups you see some cardiovascular benefit."