Salt, essential nutrient

Salt is an essential nutrient. This is a technical descriptor, not marketing hype. An essential nutrient is one required for life that the body cannot produce itself and which is required for good health. For humans, salt is as essential as water. We can perish from too little salt as we can of thirst. The human body contains about eight ounces of salt. The amount of salt is regulated in our bodies by our kidneys and by perspiration.

One component of salt, sodium (Na), is involved in muscle contraction including heartbeat, nerve impulses, and the digestion of body-building protein. Sodium is easily absorbed and is active in the absorption of other nutrients in the small intestine. Sodium is the major extracellular electrolyte responsible for regulating water balance, pH, and osmotic pressure. It is important in nerve conduction. Because of sodium's importance to your body, several interacting mechanisms, including generation of hormones angiotensin and aldosterone, adjust the system in the event of consumption of insufficient amounts of salt which would threaten the body's nerves and muscles and interference with the sodium-potassium "pump" which adjusts intra- and extra-cellular pressures. If your salt intake varies widely, these mechanisms activate to assure that your body remains healthy, maintaining a relatively constant blood pressure.

The other component of salt, chloride (Cl) is also essential to good health. It preserves acid-base balance in the body, aids potassium absorption, supplies the essence of digestive stomach acid, and enhances the ability of the blood to carry carbon dioxide from respiring tissues to the lungs.

Because salt is essential to good health, the human body is hard-wired with an innate salt appetite. Around the world, population salt intakes vary somewhat, but nearly all fall within what eminent medical researcher Bjørn Folkow termed the “hygienic safety range” of sodium intake, between 2,300 mg/day and 4,600 mg/day or even 5,750 mg/day. In common English measures, that would be one to two or two and a half teaspoons of salt per day. A few remote peoples lacking access to salt apparently consume far below 2,300 mg/day sodium while a few others who consume diets heavy with salted fish and vegetables, but virtually every society with access to salt consumes amounts within the “safety range.” Intakes in North America and most of Europe average about 3,500 md/day --- right in the middle of this range. Some public health agencies feel these intake levels are too high, but consumption levels are unchanged over the past century when medical instruments allowed accurate measurements.

Predictable consumption has made salt an ideal vehicle to fortify. Iodized salt is used by 70% of the world’s population to protect against mental retardation due to Iodine Deficiency Disorders (IDD). Many countries fortify salt with fluoride against dental caries in situations where fluoridating drinking water is inappropriate. And a growing number fortify salt with iron to prevent anemia. Learn more about iodized salt. And fluoridated salt .