Prepared by
Diane Ball Linder, EdD, LDN, RD

Sodium is needed for nerves and muscles to function as they should. Sodium helps maintain normal blood volume and blood pressure.

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Sodium

Sodium is one of the most plentiful minerals in the body. Sodium is chiefly found in the fluids that circulate outside the cells, and only a small amount of it is inside the cells. We need to understand a little about the relationship between sodium and potassium to understand how sodium functions in our body, because they work as partners. Potassium, another mineral, is located mainly inside the cells. The interrelation between amounts of these minerals in their different locations permits substances to pass back and forth between the cells and the surrounding fluids. This movement of fluids across cell membranes is called osmosis.

Sodium and potassium are important in keeping a normal balance of water between the cells and the fluids. A lowering in the sodium content of the fluids results in a transfer of water from the fluids into the cells. An increase in sodium causes a transfer of water from the cells into the fluids. All types of muscles including the heart muscle are influenced by sodium and potassium. Although potassium is very important, it is not required to be listed on the nutrition label.

Sodium is needed for nerves and muscles to function as they should. Sodium helps maintain normal blood volume and blood pressure. It occurs naturally in some foods. Sodium is added during processing of some foods to preserve or flavor. We need some sodium, but we need to be careful to not get too much sodium. Getting too much sodium increases our risk of high blood pressure. A person might experience retention of fluid or swelling with overconsumption of sodium.

Sodium is required on the nutrition label. On the nutrition label, the daily reference value for sodium is 2,400 mg. Many Americans consume six to 18 times that amount.

One way we get more sodium in our diet than we might realize is by using a lot of table salt, soy sauce, monosodium glutamate and soft water. Table salt is 40 % sodium. One teaspoon of salt contains about 2,000 mg sodium. To help people keep their sodium intake within a healthier level, they need to avoid highly salted foods and remove the salt shaker from the table. About a third of the total salt we eat comes from the salt shaker. Up to one-half comes from processed food, to which salt is added. The American Heart Association has recommended a standard of 20 milligrams of sodium per liter, to protect heart and kidney patients whose sodium intakes must be restricted. About half of the United States population drinks water containing more than 20 milligrams per liter.

Read the labels on canned, frozen and instant foods. Many are high in sodium. Unprocessed, whole foods are lower in sodium - and higher in potassium- than we might think. Don't use taste as a guide to how much sodium the food contains. Many foods high in sodium don't taste salty. For example, some cereals don't taste salty, yet cocktail peanuts do. However, those cereals may have more sodium in them than the peanuts. Salt has been added to the outside of the peanuts and our taste buds pick up on that quicker. Read the labels to be sure!

The government definitions for sodium on the nutrition label are:

Label Claim Definition - Per Standard Serving Size
Sodium Free	Less than 5 mg sodium
Very Low Sodium	35 mg or less sodium
Low Sodium	140 mg or less sodium
Reduced Sodium	At least 25 percent less sodium
Light in Sodium	50 percent less sodium

To avoid too much sodium:

• Enjoy unsalted flavors of foods.
• Cook with only small amounts of added salt.
• Add little or no salt to food at the table.
• Eat pickles, olives and other pickled foods less often.
• Cut back on eating salty or smoked meats such as lunch meats and franks, or select the lower-salt ones.
• Researchers with the Agricultural Research Service reported that just about all processed meats can be made with 20 % to 25 % less salt with no risk or spoilage.
• Select food products prepared with less sodium.
• Read labels for sodium content. Look in the list of ingredients for words that would tell you if sodium is in that food: soda, sodium or the symbol for sodium, Na. Examples would be sodium bicarbonate for baking soda, monosodium glutamate, disodium phosphate and others.
• Eat plenty of fresh fruit and vegetables.