Of all the substances added to our foods, salt (chloride of sodium) is the only one that is said to be indispensable. Many reasons are given for the use of salt and I shall discuss the most important of these in this chapter; but the two basic reasons for its use are commonly stated about as follows: 1. Salt is highly essential to animal life; and 2. Animals recognize its necessity by going to "salt-licks" for their periodic supply. I shall discuss these two basic assumptions first, after which, I shall consider some of the minor reasons for its use.
A salt is the result of the combination of a metal with an acid. There are many of these known to the chemist, as for example, sodium carbonate, sodium phosphate, etc. Only a few salts are known to the layman as such. Epsom salts, Glauber salts, Rochelle salts, smelling salts and bath salts, etc., are well-known salts. No one thinks it necessary to eat these salts daily. Although sodium, carbon and phosphorus are all essential ingredients of the living body, nobody thinks it essential to eat sodium carbonate or sodium phosphate daily. Only sodium chloride (a combination of sodium and chlorine) is thought to be essential as a daily addition to our diet.
Sodium chloride (common salt) exists in the soil and exists in all parts of the world. The waters of the ocean and salt lakes of the world are abundantly supplied with it as it is washed out of the soil by the rains and carried down the streams to the lakes and oceans. The drying up of salt lakes, of ocean arms and marshes, etc., has left large deposits of salt in many parts of the earth. Other parts are not supplied with the salt deposits. Few of these deposits are above ground. Almost all of them are covered over with and intermixed with soil. Outcroppings of salt are so rare that salt is not available to animal life in most parts of the globe.
Salt is plentiful in Northern Europe, scarce in China, Korea and India, scarce in the Malayan Peninsula , unknown in Western Africa, plentiful in North America, but scarcely known to the pre-Columbian Indians of this continent.
By and large the white man gets much salt, the yellow man some, the brown man little and the black man none at all. These facts are generally known to scientists, yet they continue to ignore the fact that whole tribes and races have maintained health and strength for many centuries without the use of salt.