How to know more (because it’s hidden where you least expect) and consume less (because you likely need to cut back).

By Dana Sullivan Kilroy
Updated May 04, 2010
Tom Schierlitz

Sodium is sneaky: Even if you’re mindful of how much salt you sprinkle on your dinner, you’re probably still ingesting far too much from other sources. Earlier this year, the American Heart Association lowered its sodium-intake recommendation for healthy people to 1,500 milligrams (mg) a day, from 2,300 milligrams. However, most Americans consume more than twice the current recommended limit, says Aram Chobanian, M.D., a hypertension expert at Boston University Medical Center. Excess sodium is linked to elevated blood pressure, which in turn increases the risk of heart attack and stroke. These kill about 100,000 Americans annually.

The Basics

Sodium is an essential nutrient that is critical for transmitting nerve impulses, contracting and relaxing muscles, and maintaining the fluid balance in your body. Table salt, or sodium chloride, is roughly 40 percent sodium and 60 percent chloride (essentially another name for the element chlorine). In addition, since 1924, manufacturers have been enriching table salt with iodine, a naturally occurring element found in dairy products and seafood, to prevent iodine deficiency, which can lead to mental impairment and an enlarged thyroid gland. If you’ve hopped on the gourmet-salt bandwagon, note that these varieties, including Celtic, Hawaiian, and sea salt, don’t contain iodine but do have the same amount of sodium as table salt.

The Downside of Sodium

The benefits of sodium and iodine don’t add up to a reason to use more salt. “You’ll get enough sodium just by consuming a well-balanced diet. It’s in many vegetables, meats, nuts, grains, and dairy foods,” says Alice H. Lichtenstein, a scientist at the U.S. Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, in Boston. And with multivitamins and the varied foods available today, few Americans are deficient in iodine. When you consume too much sodium, your kidneys must get rid of the excess. Experts theorize that if your kidneys can’t keep up, then water is pulled from cells, causing blood volume to increase, which forces your heart to work harder and puts blood vessels under more pressure. This may raise your blood pressure and, in turn, your chances of heart attack and stroke. Another issue: potassium, which works with sodium to maintain the body’s water balance. Most Americans don’t eat enough potassium-rich fruits and vegetables, says Chobanian. And, he says, “when potassium intake is low and sodium intake is high, it makes the problems associated with excess sodium worse.”

Where Sodium Is Hiding

It’s not the saltshaker you need to worry about most. “It’s the sodium in certain processed foods and beverages that really contributes to hypertension,” says Chobanian. About 10 percent of the sodium that the average person consumes comes from salt added during cooking and at the table. Another 10 percent or so is found naturally in foods. And about 75 percent is from processed foods and restaurant meals, says Jeannie Gazzaniga-Moloo, a spokesperson for the American Dietetic Association and a registered dietitian in Roseville, California. Here are common places you’ll find sodium.

At restaurants: When dining out, you cede control. There’s no way to know what ingredients the chef started with or how much salt she added.
At drive-throughs: Sodium, whether in table salt or some other ingredient, is also used to preserve foods (sodium propionate or sodium aluminum sulfate is in fast-food flour wraps, for example) and as a flavor enhancer to mask bitterness and make meats juicier. Most frozen fries contain about 250 milligrams of sodium per serving, but a serving of homemade oven fries has only 15 milligrams, if unsalted. (For a flavor boost, sprinkle on some dried oregano.)
At the coffee shop: It lurks in drinks and foods that don’t necessarily taste salty. That large caramel-laced frozen coffee drink with whipped cream can pack around 250 milligrams of sodium. “Baked goods, including doughnuts, muffins, cookies, and bread, tend to be high in sodium, too,” says Gazzaniga-Moloo.
At the grocery store: A good rule of thumb is, if it comes in a box (pancake mixes, instant cereals), a bottle (salad dressings), or a can, check the label. Even some canned vegetables can be salt bombs (a half cup of canned diced tomatoes has more than 250 milligrams of sodium).

How to Consume Less Sodium—Without Feeling Deprived

When scanning labels, look for the sodium content for one serving and particularly its “percent daily value,” which indicates how much the item cuts into the old recommended daily-sodium limit. (To stay below the new 1,500-milligram limit, aim to consume a total of 62.5 percent of the daily limit.) If the item is going to be an ingredient in a recipe (a marinade for chicken, say), look for low- or no-salt-added varieties, as sodium quickly adds up when combined with other foods. If you use a canned product (like tuna or beans), rinse it to remove some sodium. Food manufacturers are also cutting back in places. Kraft, for example, plans to reduce sodium in its foods by an average of 10 percent over the next two years.

There are also easy, creative ways to add flavor without adding salt. A squeeze of lemon juice or a dash of vinegar will enhance fresh vegetables. Or try cumin, nutmeg, black pepper, tarragon, or oregano. Even the new salt substitutes (such as NutraSalt) don’t leave the bitter aftertaste of early versions. You’ll be surprised at how fast you stop craving sodium. “It takes just a few weeks to get used to how food tastes with less salt,” says Gazzaniga-Moloo. And you won’t miss the bloat that comes with sodium overload.

So how much sodium is packed into those French fries above? Most frozen fries contain about 250 milligrams of sodium per serving, but a serving of homemade oven fries has only 15 milligrams, if unsalted. (For a flavor boost, sprinkle on some dried oregano.) See if you know which favorite foods are higher in sodium; take our quiz.