This section is from the book "The Natural Food Of Man", by Emmet Densmore. Also available from Amazon: How Nature Cures Comprising a New System of Hygiene.
"Another fact comes to light in this investigation, that the plant-eating animals require more common salt than the flesh-eating ones. Some of them are so greedy for salt that they will travel long distances to salt-licks in order to obtain it, which is never the case with carnivorous animals. Now, if we compare the food of the flesh-eaters with that of the herbivora, we find about the same amount of chloride of sodium (common salt), but the amount of potash salts in the food of vegetable-eating animals is from two to four times as great. Bunge suggests that the reason why the vegetable-eaters require more salt is to decompose or change the form of the great excess of potash salts, which we have seen may be very injurious; or may not the potash draw so heavily on the chloride of sodium in the body as to make the addition of it in our food necessary in order to maintain the equilibrium of the body ? In order to test this question scientifically, Bunge made an experiment on himself. First, he ate food for five days with such exactness as to bring the excretion of the salts to a regular and constant amount. On the fifth day he added to his food eighteen grammes of phosphate of potash. Although he had not added any chloride of sodium, there was not only an immediate increase of excretion of potash salts, but of soda salts also. Repeated experiments gave the same results. He estimated that, by the addition of twelve grammes of potash salts to the food, nearly half of the soda salts of the blood would be extracted. This, he thinks, proved his hypothesis. Potash in small quantities withdraws from the body chloride and sodium, or its oxide, soda, both constituents of common salt, and this requires the addition of it to our food.
"It may be seen at a glance that all vegetables contain less soda than milk; and they all contain, rice excepted, more potash than this article. If potash, as shown by Bunge, withdraws soda from the body, it may be seen that the addition of common salt to the food poor in soda is a scientific necessity.
"We also see why a babe nourished on its mother's milk does not require the addition of common salt. Its food contains less potash salts and more soda salts than almost any other article of food.
"Liebig remarked that there seemed to be a popular instinct to add more salt to those articles of food which were rich in starch, as, for instance, wheat-meal, peas and beans, and it seems that these are the very ones which contain most potash.
"In this connection it may be remarked that potash salts in large quantities affect unfavourably the mucous membrane of the digestive tract, and especially the stomach. Consequently, all those who suffer from weakness of the stomach should avoid potatoes, and substitute rice instead. Rice is also more easily digested than potatoes for other reasons. It contains less cellular or woody and indigestible matter enclosing the starch cells. One writer on food (Mulder) goes so far in his opposition to potatoes as an article of diet as to declare it would be a blessing to the race to banish them from the planet and substitute rice.
"Dr. Bunge has collected facts concerning the use of salt among various people. He finds that those who live mainly on flesh, as hunters, fishermen, and nomadic tribes, do not care for salt. Of the Samoyden he says : 'They know nothing of bread, and but little of roots. Flesh and fish constitute their daily food. The use of salt is unknown, though easily attainable from the sea. The Tungusen eat no raw flesh, but cook it in fresh water and use no salt on it. The Dolganen and Juralkan, in North Siberia, possess many salt mines, but they never use salt, unless as a medicine. Their food is fish and reindeer flesh.'Wrange writes concerning the Tschuktschen : 'Their food is flesh, and they use no salt, but have actual repugnance to it.'
"Prof. Schwartz dwelt in the land of the Tungusen three years; lived on the flesh of wild birds and reindeer without the addition of salt, and felt no need for it.
"There are tribes of flesh-eating men in both tropical India and Africa who use no salt; they even laugh at those who do use it.
"On the other hand, most of the native tribes of Africa cultivate the soil. Mungo Park says : 'The Mandigos breakfast early on porridge made of meal and water, flavoured with the rind of tamarind to give it relish. About two they eat a meal consisting of pudding made of corn meal, milk, and vegetable butter. Their chief meal is eaten late at night» and consists of broth made with corn-meal, wheat-meal with vegetables, with sometimes a little flesh and vegetable butter. They are principally Vegetarians.' Concerning salt, he says : 'They have a great craving for it. If a child gets a piece of rock-salt from a European, it eats it as our children do sugar. The poorer classes look upon a man who can afford salt as a rich man.' Park's own experience was that he had a painful craving for salt, which could not be described. On the west coast of Africa a man would sell his wife or child for salt. A war for a salt-spring between different tribes is not uncommon. To them salt is no luxury, but a necessity. . . .
"Many of the facts and statements of this chapter are drawn from German sources, and especially from a little work entitled, 'Die Modernen Principien der Ernahrung,' nach v. Pettenkofer und Voit, von Dr. Aug. Guckerston, a most valuable little work, putting in popular language the scientific experiments of the most learned German students of man's food - a subject now attracting more attention than at any former time."
We have in this a direct and conclusive proof that salt is needed in a diet of cereals and pulses; ergo, if salt is an unnatural and injurious substance, cereals, pulses, and vegetables do not form any portion of the natural food of man.
There are those among us who proudly announce themselves Vegetarians from the ethical side of this question, who speak slightingly of health considerations, designating these as selfishness, and defining Humaneness to be sympathy for the sufferings of animals. I am of a different opinion; to my mind, the reduction of the sufferings of animals is well, is humane - the reduction of the sufferings of human beings is better, is humaner. Further, I am of opinion that lack of health and premature death are productive of far more misery on the earth than all other causes combined, and whoever does most to lead the race back to health, longevity, and consequent usefulness, wins the grand prize - becomes the first apostle of humaneness.