consist of three sets of numbers. The Recommended
Dietary Allowance (RDA) defines the average daily
amount of the nutrient needed to meet the health
needs of 97–98% of the population. The Adequate
Intake (AI) is an estimate set when there is not enough
information to determine an RDA. The Tolerable
Upper Intake Level (UL) is the average maximum
amount that can be taken daily without risking neg-
ative side effects. The DRIs are calculated for children,
adult men, adult women, pregnant women, and
breastfeedingwomen.
The IOM has not set RDAs for sodium, but
instead it has set AI levels for all age groups based
on observed and experimental information about the
amount of sodium needed to replace what is lost by a
moderately active individual each day. Sodium is lost
in both urine and sweat. IAs for sodium are measured
in milligrams (mg). UL levels have not been set. How-
ever, the IOM recommends that adults limit their
sodium intake to less than 2,400 mg per day, and the
American Heart Association recommends an adult
daily intake of 1,500–2,300 mg.
The following list gives the recommended daily
AL levels of sodium for each age group.
children birth–6 months: AI 120 mg
children 7–12 months: AI 370 mg
children 1–3 years: AI 1,000 mg
children 4–8 years: AI 1,200 mg
children 9–13 years: AI 1,500 mg
adolescents 14–18 years: IA 1,500 mg
adults age 19–50: AI 1,500 mg
adults ages50–70 1,300 mg
adults 71 years or older: AI 1,200 mg
pregnant women: IA 1,500 mg
breastfeeding women: AI 1,500 mg
Sources of sodium
Many people think that the main source of salt in
their diet is what they add to food when they are
cooking or at the table while eating. In reality, more
than three-quarters of the sodium in the average
American’s diet is added to food during processing.
Another 12% is already naturally in the food. For
example, 1 cup of low-fat milk contains 110 mg of
sodium. About 6% of sodium in the diet is added as
salt during cooking and another 5% from salting food
while eating.
Although most sodium in diet comes from salt,
other sources of sodium include preservatives and
flavor enhancers added during processing. Sodium con-
tent is required to be listed on food labels of processed
foods. Some common ‘‘hidden’’ sources of sodium
include:
baking soda
baking powder
disodium phosphate
monosodium glutamate (MSG)
sodium nitrate or sodium nitrite
Below are some common foods and their sodium
content.
table salt, 1 teaspoon:2,300 mg
dill pickle, large: 1731 mg
canned chicken noodle soup, 1 cup: 850–1,100 mg
ham, 3 ounces: 1,000 mg
sauerkraut, 1/2 cup: 780 mg
pretzels, 1 ounce: 500 mg
potato chips, 1 ounce: 165–185 mg
soy sauce, 1 teaspoon: 304
deli turkey breast, 1 ounce: 335 mg
Fresh fruits, vegetables, unsalted nuts, and rice,
dried beans and peas are examples of foods that are
low in sodium.Sodium and health
Too high a concentration of sodium in the blood
causes a condition called hypernatremia. Too much
sodium in the diet almost never causes Hypernatremia.
Causes include excessive water loss (e.g. severe diarrhea),
restricted water intake, untreated diabetes (causes water
loss), kidney disease, andhormonal imbalances. Symp-
toms include signs ofdehydrationsuch as extreme thirst,
dark urine, sunken eyes, fatigue, irregular heart beat,
muscle twitching, seizures, and coma.
Too low a concentration of sodium in the blood
causes hyponatremia. Hyponatremia is not usually a
problem in healthy individuals, although it has been
known to occur in endurance athletes such as ultra-
marathoners. It is common in seriously ill individuals
and can result from vomiting or diarrhea (extreme lossKEY TERMS
Diuretic—a substance that removes water from the
body by increasing urine production
Ion—an atom or molecule that has an electric
charge. In the body ions are collectively referred
to as electrolytes.Sodium