According to Dr. Haig, human metabolism (the process by which food is converted into living tissue) differs widely from that of the carnivora. The carnivore is provided with the means to dispose of such poisonous salts as are contained in and are produced by the ingestion of animal flesh, while the human system is not so provided. In the human body these poisons are not held in solution, but tend to form deposits and consequently are the cause of diseases of the arthritic group, conspicuously rheumatism.
There is sometimes some misconception as regards the distinction between a frugivorous and herbivorous diet. The natural diet of man consists of fruits, farinacea, perhaps certain roots, and the more esculent vegetables, and is commonly known as vegetarian, or fruitarian (frugivorous), but man's digestive organs by no means allow him to eat grass as the herbivora—the horse, ox, sheep, etc.—although he is much more nearly allied to these animals than to the carnivora.
We are forced to conclude, in the face of all the available evidence, that the natural constitution of man closely resembles that of fruit-eating animals, and widely differs from that of flesh-eating animals, and that from analogy it is only reasonable to suppose that the fruitarian, or vegetarian, as it is commonly called, is the diet best suited to man. This conclusion has been arrived at by many distinguished men of science, among whom are the above mentioned. But the proof of the pudding is in the eating, and to prove that the vegetarian is the most hygienic diet, we must examine the physical conditions of those nations and individuals who have lived, and do live, upon this diet.
It might be mentioned, parenthetically, that among animals, the herbivora are as strong physically as any species of carnivora. The most laborious work of the world is performed by oxen, horses, mules, camels, elephants, all vegetable-feeding animals. What animal possesses the enormous strength of the herbivorous rhinoceros, who, travellers relate, uproots trees and grinds whole trunks to powder? Again, the frugivorous orang-outang is said to be more than a match for the African lion. Comparing herbivora and carnivora from this point of view Dr. Kingsford writes: 'The carnivora, indeed, possess one salient and terrible quality, ferocity, allied to thirst for blood; but power, endurance, courage, and intelligent capacity for toil belong to those animals who alone, since the world has had a history, have been associated with the fortunes, the conquests, and the achievements of men.'
Charles Darwin, reverenced by all educated people as a scientist of the most keen and accurate observation, wrote in his Voyage of the Beagle, the following with regard to the Chilian miners, who, he tells us, live in the cold and high regions of the Andes: 'The labouring class work very hard. They have little time allowed for their meals, and during summer and winter, they begin when it is light and leave off at dusk. They are paid £1 sterling a month and their food is given them: this, for breakfast, consists of sixteen figs and two small loaves of bread; for dinner, boiled beans; for supper, broken roasted wheat-grain. They scarcely ever taste meat.' This is as good as saying that the strongest men in the world, performing the most arduous work, and living in an exhilarating climate, are practically strict vegetarians.
Dr. Jules Grand, President of the Vegetarian Society of France speaks of 'the Indian runners of Mexico, who offer instances of wonderful endurance, and eat nothing but tortillas of maize, which they eat as they run along; the street porters of Algiers, Smyrna, Constantinople and Egypt, well known for their uncommon strength, and living on nothing but maize, rice, dates, melons, beans, and lentils. The Piedmontese workmen, thanks to whom the tunnelling of the Alps is due, feed on polenta, (maize-broth). The peasants of the Asturias, like those of the Auvergne, scarcely eat anything except chick-peas and chestnuts ... statistics prove ... that the most numerous population of the globe is vegetarian.'
The following miscellaneous excerpta are from Smith's Fruits and Farinacea:—
'The peasantry of Norway, Sweden, Russia, Denmark, Poland, Germany, Turkey, Greece, Switzerland, Spain, Portugal, and of almost every country in Europe subsist principally, and most of them entirely, on vegetable food.... The Persians, Hindoos, Burmese, Chinese, Japanese, the inhabitants of the East Indian Archipelago, and of the mountains of the Himalaya, and, in fact, most of the Asiatics, live upon vegetable productions.'
'The people of Russia, generally, subsist on coarse black rye-bread and garlics. I have often hired men to labour for me. They would come on board in the morning with a piece of black bread weighing about a pound, and a bunch of garlics as big as one's fist. This was all their nourishment for the day of sixteen or eighteen hours' labour. They were astonishingly powerful and active, and endured severe and protracted labour far beyond any of my men. Some of these Russians were eighty and even ninety years old, and yet these old men would do more work than any of the middle-aged men belonging to my ship. Captain C. S. Howland of New Bedford, Mass.'
'The Chinese feed almost entirely on rice, confections and fruits; those who are enabled to live well and spend a temperate life, are possessed of great strength and agility.'