Hidden Sources of Sodium in the Diet

Why is sodium added to food?

Salt (sodium chloride) serves a number of purposes. This white crystal has been used as a preservative for meats and vegetables and flavoring agent for centuries. It helps prevent spoiling by inhibiting the growth of bacteria, yeast, and mold. Salt also enhances flavor in food. For example, it accentuates sweetness in cakes and cookies and helps disguise metallic or chemical aftertastes in products such as soft drinks. Additionally, salt is used as a color developer, binder, texturizer, and fermentation control agent, e.g., in bread baking. For these reasons, salt is added to foods such as ham, sausage, bacon and other meat products, smoked fish and meats, canned vegetables, butter, margarine and spreads, cheese, bread, sauces, condiments, pasta sauces, soups, savory snack foods, salad dressings, and breakfast cereals. Salt also reduces the perception of dryness in foods such as crackers and pretzels (18, 22). However, many food and nutrition experts agree that processed foods need not contain the high levels of salt they currently do.

Salt Facts:

• More than 90% of sodium occurs as salt (sodium chloride, NaCl).
• Sodium chloride, or table salt, is approximately 40% sodium.
• More than 75% of salt intake is derived from processed foods, just under 15% from natural sources, about 10% is added during cooking or when eating, and 1% comes from tap water.
• Cereal products including breakfast cereals, bread, cakes, and biscuits provide about a third of the salt in our diet.
• Meat and meat products provide just over a quarter of the salt in our diet.
• In addition to sodium chloride, there is a wide variety of other forms of sodium in our diet, many of which are used as additives in food processing, usually to add flavor, texture, or as a preservative. For example, monosodium  glutamate is commonly used as a flavor enhancer.
• Sodium and chloride levels are comparatively low in all foods which have not been processed. Since most foods in their natural state contain sodium, you need to be aware of both natural and added sodium content when you  choose foods to lower your sodium intake. But most sodium in our diet is added to food while it is being commercially processed or prepared at home.

Primary dietary sources of sodium: According to Xavier Pi-Sunyer, MD, MPH, a member of the 2010 and 2005 Dietary Guidelines Advisory Committee (DGAC), Professor of Medicine at Columbia University College of Physicians and Surgeons, and Chief of the Division of Endocrinology, Diabetes, and Nutrition at St. Lukes-Roosevelt Hospital Center in New York City, Americans today consume an average of  3,400 mg of sodium a day — much more than recommended (12). The most common dietary sources of sodium include (10):

• Processed, packaged, and prepared foods: The vast majority of sodium in the typical American diet, approximately 75%, comes from processed foods that are sold packaged or prepared at supermarkets and other stores (17, 22). These foods are typically high in salt, which is a combination of sodium and chloride, and in additives that contain sodium. Processed foods include baked goods, bread, prepared meals, “TV” dinners, meat and egg dishes, pizza, bacon, cold cuts, cheese, soups, and fast foods (Additional food items listed below).

• Natural sources: Some foods naturally contain sodium. These include all vegetables and dairy products such as milk, meat, and shellfish. While they do not have an abundance of sodium, eating these foods does add to your overall sodium intake. For example, 1 cup (237 milliliters) of low-fat milk has about 107 mg of sodium.

• In the kitchen and at the table: Most of the sodium that Americans consume doesn’t really come from salt added during cooking or at the table. However, many recipes call for salt, and some people salt their food at the table. Condiments may also contain sodium.

Sodium content in some unprocessed foods (16):

Fresh foods higher in sodium:

Milk, 120 mg. per cup

Scallops, 260 mg. per 3 oz.

Fresh meats: about 30-70 mg. per 3 oz. (Chicken, beef, fish, lamb, pork)

Fresh vegetables: about 30-50 mg. per 1/2 cup (Celery, Chinese cabbage, sweet potatoes)

Fresh vegetables: about 10-20 mg. per 1/2 cup (Broccoli, brussels sprouts, carrots, corn, green beans, legumes, potatoes, salad greens)

Grains: (cooked without salt), about 0-10 mg. per 1/2 cup (Barley, oatmeal, pasta, rice)

The top 10 individual food sources of sodium in the American diet according to the National Health and Nutrition Examination Surveys which evaluated the combination of each item’s sodium content and frequency of consumption (5, 18):

1. Meat pizza
2. White bread
3. Processed cheese
4. Hot dogs
5. Spaghetti with sauce
6. Ham
7. Catsup
8. Cooked rice
9. White rolls
10. Flour tortillas

Sodium content in some common seasonings, sauces, salad dressings, and processed foods (8, 16):

• Salts, 1 tsp: 2,000-2,300 mg (Table salt, sea salt, seasoned salt, onion salt, garlic salt): Herb seasoning blends may contain different sodium concentrations, so read labels.

• Baking powder, 1 tsp: 339 mg.

• Chili powder, 1 tsp: 26 mg.

• Garlic salt, 1 tsp: 2,050 mg.

• Onion salt, 1 tsp: 1620 mg.

• Horseradish, 1 tbsp: 165 mg.

• Meat tenderizer, 1 tsp: 1680 mg.

• Mustard, prepared Dijon, 1 tsp: 126 mg.

• Green olives, 4: 323 mg.

• Dill pickle, large: 1731 mg

• Chili sauce, 1 tbsp: 227 mg.

• Ketchup, 1 tbsp: 168 mg.

• Soy sauce, 1 teaspoon: 304 mg. (1 tbsp: 1029 mg.)

• Tabasco, 1 tsp: 66 mg.

• Worcestershire, 1 tbsp: 147 mg.

• French dressing, 1 tbsp: 214

• Mayonnaise, 1 tbsp: 78 mg.

• Thousand Island, 1 tbsp: 109 mg.

• Canned chicken noodle soup, 1 cup: 850-1,100 mg

• Canned pasta, about 800-1,000 per serving (Beefaroni, macaroni and cheese, ravioli)

• Canned vegetables, about 200-450 mg. per 1/2 cup (Carrots, corn, green beans, legumes, peas, potatoes)

• Ham, 3 ounces: 1,000 mg

• Foods prepared in brine, about 300-800 mg. per serving (2 fillets anchovies, 1 dill pickle, 5 olives, 1/2 cup sauerkraut)

• Sauerkraut, 1/2 cup: 780 mg

• Processed cheeses, about 550 mg. per 1 1/2 oz. (American, Cheddar, Swiss)

• Instant puddings, about 420 mg. per 1/2 cup (All flavors)

• Pretzels, 1 ounce: 500 mg

• Potato chips, 1 ounce: 165-185 mg

• Deli turkey breast, 1 ounce: 335 mg

• Hot dogs, about 500-700 mg. per 2 oz. (Hot dogs, smoked sausages)

• Smoked and cured meats, about 700-2,000 mg. per 2 oz. (Canned ham products, corned or chipped beef, ham, lunchmeats)

• Fast foods and TV dinners, about 700-1,500 mg. per serving [Breakfast biscuit (cheese, egg, and ham), cheeseburger, 10 spicy chicken wings, frozen TV dinners, 2 slices pizza, taco, vegetarian soy burger on bun]

• Dry soup mixes (prepared), about 1,000-2,000 mg. per 1 cup (Bouillon cube or canned, noodle soups, onion soup, ramen)

• Cereals, dry ready-to-eat, about 180-260 mg. per 1 oz. (Cheerios, cornflakes, corn bran, Cocoa Puffs, Total, others)

“Hidden” sources of sodium in the diet: Although most sodium in food comes from salt, other sources of sodium include preservatives and flavor enhancers added during processing. Sodium content is required to be listed on food labels of processed foods.

• Natural foods: Most foods such as vegetables, meat, shellfish, and dairy products including milk, contain low amounts of sodium in their natural state. Some natural foods such as cheeses, seafood, olives, and legumes may have a higher-than-expected sodium content.

• Drinking water derived from a home water softening system: However, softened water which has passed through a reverse-osmosis filtration system generally has negligible sodium levels.

• Processed foods such as canned, frozen and prepared foods: Approximately 75-77% of sodium in the American diet comes from prepared or processed foods and cold cuts like bread, bagels, crackers, cheese, cold cuts, bacon, hotdogs, pasta, pizza, potato chips, pretzels, tomato sauce, soups, condiments, canned foods, prepared mixes, “fast foods,” ready-to-eat meals and prepared frozen foods. When buying prepared and prepackaged foods, read the labels. Many different sodium compounds are added to foods. These are listed on food labels. Watch for the words “soda” and “sodium” and the symbol “Na” on labels; these words show that sodium compounds are present. The American Heart Association (AHA) is working with federal agencies to determine how to reduce the amount of sodium in the food supply and is also encouraging food manufacturers and restaurants to reduce sodium in foods by 50% over a 10-year period.

• Additives and Condiments: Capers, ketchup, mustard, relish, dips, salad dressings, barbecue and other sauces, seasoning mixtures and packets, soy sauce (Choose low-sodium soy sauce when available).

• Baked goods prepared from mixes or sold commercially: White bread, rolls, flour tortillas

• Flavored soda beverages: Cherry soda, Coca Cola, Pepsi, Ginger Ale, Seven-Up, Mountain Dew, Root Beer, etc., contain sodium benzoate as a preservative. Avoid mixing soda containing sodium benzoate with juices or juice drinks containing ascorbic acid (vitamin C), since the combination can cause benzoate to chemically change to benzene, and increase the risk of cancer or leukemia.

• Table salt (sodium chloride): Used in cooking, seasoning at the table, canning and preserving.

• Salted butter, dips, spreads

• Frozen dinners

• Ready-to-eat cereal

• Vegetable juices: Choose low-sodium varieties when available

• Canned vegetables and legumes: Choose sodium-free varieties when available. Dry beans are virtually sodium-free.

• Cured meats

• Packaged deli meats

• Commercially-prepared soups

• Marinades and flavorings

• Restaurant meals, including baked goods, casseroles, dressings, entrees, marinades, sauces, soups: Fish, steamed vegetables, and salad with olive oil and vinegar or dressing on the side tend to be lower-sodium choices at a restaurant. Request that salt be omitted from whatever you do order, though. Low-sodium dessert options include fruit, ice cream, sherbet, or angel food cake.

• Salted nuts: Choose plain, unsalted nuts

• Seasoning  and spice mixtures and packets

• Snack foods: Cheese puffs, flavored popcorn, potato chips, pretzels, tortilla chips, etc.

• Some over-the-counter drugs: Some over-the-counter medications contain high levels of sodium. Carefully read the label before buying an over-the-counter drug. Look at the ingredients list and warning statements to see if sodium is mentioned. A statement of sodium content must appear on labels of antacids containing 5 mg. or more per dosage unit (table- or teaspoon). Some companies produce low-sodium, over-the-counter products. If in doubt, ask a healthcare professional.

• Some prescription medications: Some headache or heartburn medicines contain sodium carbonate or bicarbonate. Read the ingredient list and warning statement to be sure. Consumers can’t tell by looking at a bottle whether a prescription drug contains sodium. If you have high blood pressure, ask your physician or pharmacist about the sodium content of prescription medications. Regardless, never stop taking your prescribed medication without first checking with your doctor.

• Baking soda (sodium bicarbonate): Sometimes used to leaven breads and cakes; sometimes added to vegetables in cooking; used as alkalizer for indigestion. (1 teaspoon of baking soda = 1,000 mg. sodium)

• Baking powder: Used to leaven quick breads and cakes.

• Disodium phosphate: An emulsifier to prevent oil from separating from the the rest of the mixture, leavening and texture-modifying agent used to change the appearance or feel of food and increase the shelf life of food. Found in some quick-cooking cereals and processed cheeses.

• Monosodium glutamate (MSG): Flavor enhancer

• Na: Chemical abbreviation for sodium

• NaCl : Chemical abbreviation for sodium chloride (table salt)

• Sodium alginate: A flavorless gum used to increase viscosity, produce a gel-like consistency, and as an emulsifier. Used in many chocolate milks and ice creams to make a smooth mixture.

• Sodium ascorbate: Vitamin C

• Sodium benzoate: A preservative in many condiments such as relishes, sauces and salad dressings, as well as in numerous soda beverages.

• Sodium bicarbonate (baking soda): Leavening agent (See “Baking soda” above)

• Sodium caseinate

• Sodium chloride: Table salt

• Sodium citrate: Acidity controller

• Sodium hydroxide: Used in food processing to soften and loosen skins of ripe olives and certain fruits and vegetables.

• Sodium nitrate or nitrite: Meat-curing agent in bacon, ham, salami, sausages, etc.

• Sodium propionate: Mold inhibitor used in pasteurized cheese, some breads, and cakes.

• Sodium saccharin

• Sodium stearoyl lactate (SSL): A dough conditioner, emulsifier, foaming agent, stabilizer, shelf-life enhancer, fat and sugar replacer (due to it’s mildly sweet taste). SSL is often used in baked goods, bread, salad dressings, sour cream, cheese products, crackers, cookies, and puddings.

• Sodium sulfite: Used to bleach certain fruits such as maraschino cherries and glazed or crystallized fruits that are to be artificially colored; also used as a preservative in some dried fruits such as apricots, prunes, etc..

• Soy sauce

• Trisodium phosphate

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