Sodium chloride—also known as salt—is necessary to help your body maintain fluid balance, help your muscles relax and your nerves transmit signals. Sodium chloride also helps maintain normal blood pressure. One of salt’s earliest roles was to preserve food (it does this by drawing out water, preventing bacteria from growing). Today, it gets a bad reputation (and deservedly so) because Americans eat too many processed foods and therefore consume more salt than necessary, which results in adverse health effects.
Although they’re two separate minerals, sodium and chloride are usually found together in most foods (and account for about 90 percent of sodium intake in the U.S.); for this reason, they are presented together here.
Since most of us consume quite enough salt in our diets, this might be one nutrient you need to think about limiting. You can generally assume that fruits, vegetables and legumes are low in sodium unless salt has been added during cooking. (One teaspoon of salt contains about 2,300 milligrams, or 2.3 grams, of sodium.)
Most of the salt consumed in a typical diet comes from processed food, such as salted meats, nuts and cold cuts; margarine and butter; chips, hot dogs and pretzels; and canned vegetables and bottled sauces.
A sodium chloride deficiency is not likely unless you have been experiencing persistent diarrhea or vomiting, excessive use of diuretics, or you have kidney problems or other medical conditions that result in loss of sodium. If it happens, symptoms can include headache, nausea, vomiting, dizziness, muscle cramps, disorientation and fainting. Excessive fluid intake has been shown to induce a condition called hyponatremia in which sodium is diluted to abnormally low amounts in the body. This has been seen in marathon runners and other athletes who consume large amounts of water in relatively short periods of time. Symptoms of this condition are similar to the above but can advance into more severe complications including seizures, coma, brain damage and death.
High blood pressure can result from too much salt in the diet, which can increase your risk of heart disease and stroke. Individuals more sensitive to the effects of high salt intakes include those with existing high blood pressure, diabetes, chronic kidney disease; the elderly; and African-Americans. A diet high in potassium or low in fat can slightly offset increases in blood pressure due to high salt intakes. However, it’s best to limit salt intakes to recommended levels.
The following table lists the recommended intake for healthy people based on current scientific information.