Popular Science Monthly/Volume 5/September 1874/Food and the Development of Man
THE progress of science does not consist merely in the discovery of new facts and the enlargement of our knowledge, or even in the ingenious conclusions thence drawn, and which, from their universality, acquire the character of laws; its mightiest work is the change it brings about in our fundamental conceptions, and the consequent revolution in science itself. As science advances, it gains new principles, new arguments; its problems and its aims multiply incessantly. There is no branch of knowledge that has not experienced this, and even historical investigation is no exception. Time was when the earth used to be regarded as merely the temporary abode of man, or even as the place where he spent a brief term of banishment. The history of man used to consist of casual events, or of the free and arbitrary doings of individuals. Great men, great heroes, great rulers, great thinkers, determined the history of peoples and of states. Trifling causes—the walling up of a window, or the spilling of a glass of water— might occasion events that would convulse the world. By the aid of natural science we have come to look on the earth as something more than the temporary abode, as the true home and school of mankind. Man has become a child of Nature; in Nature are all the conditions of his life and development. Climate and soil, the conformation of the land, and the distribution of water, determine the physical and the mental development of nations. It has long been seen that peoples differ, that their history and their civilization are different, accordingly as they live in valleys or on mountains, in islands or in the interior of continents, in deserts and steppes or in forests, in an open, hilly country, or in sequestered valleys. Historical research, however, has but recently begun to concern itself with the natural causes of the development of civilization, and many an important aspect of this subject is still entirely overlooked.
Of all the influences which determine the life of the individual, and on which his weal and woe depend, undoubtedly the nature of his food is one of the weightiest. Every one has for himself experienced how not only the strength of his muscles, but also the course of his thought and his whole mental tone, is affected by the nature of his food. And shall not that hold good for nations which holds good for individuals? Shall the sum of mankind be less affected in their physical and mental development by the food they take, than the individuals of whom that sum is made up? This seems to be the decision of history. Philosophers (even the great thinker of Königsberg himself) have not a word to say about the influence on human races and peoples of different food-supplies. The world heard at first with astonishment the saying of a famous scientific man, that, "could man live on air and water alone, such notions as master and servant, prince and subject, friend and foe, hate and love, virtue and vice, right and wrong, etc., would have no existence, and political communities, social and family life, human intercourse, commerce, trade, and industry, art and science—in a word, whatever makes man what he is—depend entirely on the fact that man possesses a stomach and is subject to a law of Nature which compels him daily to take a certain amount of food."
As we start out with the principle, too late recognized in historical research, that the selection of articles of food is not only important for the personal well-being of the individual, but that it is a weighty, world-stirring question for countries and nations in its bearings on the history of civilization, we will, therefore, endeavor to look closely into it, and study the mode in which this influence is exerted.
If nations are to flourish, they, no less than individuals, need wholesome, strong food. The only question is, How are we to determine what food is strong and wholesome? Foods have been classed in different groups, according to the influence they have on the body, in virtue of their essential constituents; and though this classification, like every artificial classification we make in Nature, is only approximately correct, still it gives us some ground to stand on. Blood-formers, or albuminates, are those albuminous materials which constitute the nutritive elements of the blood, and enter into the composition of the muscles, bones, sinews, and ligaments, on which the exercise of force specially depends. The heat-producers or respiratory foods are those rich in carbon; these specially serve to support, with the aid of inspired oxygen, the process of combustion so necessary for the purposes of the organism. Finally, there is a third group of nutritious substances—the nutritive salts—which are of an inorganic nature, and which, after combustion of the food, remain in the shape of ash.
All these food-materials are essential, since with them the organism is built up. Life is an unceasing process of waste and repair, and the food must make good the loss the organism suffers every instant. Even those substances which are contained in the living body only in small quantities must be supplied, for on this depends the activity of important organs. Such substances are common salt, potash, lime, magnesia, phosphoric acid, and, above all, iron, without which the blood-corpuscles would lose their vitality. But none of these groups is, by itself, sufficient for nutrition; they must all be combined. Blood-formers, heat-producers, and nutritive salts, are not separately foods, but only factors of food, each as indispensable for the vital processes as air and water, but each incapable by itself of supporting life. One cannot live on albumen alone or on fat alone. Without lime-phosphate no bone would be formed, no matter how much pure albumen and fat we ate; and without albumen no muscular tissue would be formed, though we were to gorge ourselves with sugar and salt; finally, without fat, no brain. But we properly enough give the name of foods to meat, milk, and bread, for in them all the three conditions are present.
Fortunately, these nutritive principles are found by no means sparingly distributed throughout Nature; under the most varied forms they occur in almost every food-stuff used by man. We not only find the blood-formers in the shape of fibrine in the blood and muscles of animals, of albumen in eggs, of casein in milk, of lime and areolar tissue in cartilage, sinew, and skin, but also in the vegetable kingdom; we discover them in the gluten of grains, in the legumine of pulse, in the vegetable albumen of sundry roots, leaves, and fruits. Heat-producers are furnished, not only by the animal kingdom in its fats, but by plants also. Sundry seeds give a small quantity of oil, but the principal supply of heat-producing elements derived from the vegetable world appears in the shape of starch, gum, and sugar—substances which, during the process of digestion, are transformed into fats, and therefore may replace the latter. Finally, we have salts in the water we drink, and more abundantly in nearly every animal and vegetable substance we consume. Hence, it might seem to be an easy thing to find wholesome food, as though one had only to seize blindly the store of food offered by Nature, in order to get all that our organism requires to keep it vigorous. But it is not to be forgotten that, while the nutritive elements make up the losses of the organism, and renew the body, as it were, still they must be taken in certain definite proportions. Now, in Nature they are not distributed in any such proportion. There the greatest diversity is found; one food-stuff consists principally of blood-formers, another of heat-producers; this one contains only one of the nutritive salts, that one, another. If, then, we let chance decide in this matter, it might easily happen that we would take one element in excess, while we took none at all of another. If this were the case again and again, or permanently, the organism must suffer or perish utterly; for, suppose only a single organ to be improperly nourished, i. e., to receive food insufficient to make up its losses, the check given to this one will affect all the rest. Science can now pretty accurately determine the composition of every article of food, and hence its contents of the various nutritive principles. This is done by chemical analysis. Chemical analysis, however, is of little assistance to us in determining accurately the constituents of our daily food. For, if one, being over-anxious on this point, wished to avoid all danger by having all his food examined by a chemist, so as to apportion by weight the amount of this substance and of that which he should take, there is reason to fear that he would die of hunger long before the chemist had concluded the analysis. Fortunately, there is a better method of avoiding danger, and of this we wisely make use under other circumstances. When we would protect ourselves against the chance which gives up our houses to destruction by fire, or when we would secure our dependents against the accident which deprives us of life and them of a protector, we take out an insurance policy on house or life. But this insurance is not a transaction between two or three, but between hundreds of thousands and millions. A mutual insurance transacted between three persons were a game of chance, between millions it is a sure calculation. We defeat chance, when we share it with others. To apply all this to the matter in hand: we must not restrict ourselves to a few articles of food, but must have a great variety of foods to select from; we must not partake of the same fare day after day, but must vary it as much as possible. Only with a varied and alternating dietary can we be sure that what is lacking in one food-stuff will be supplied in another, and that what we fail to get to-day we shall have to-morrow. What is commonly regarded as simply the result of a spoilt palate, viz., the repugnance excited by the steady recurrence of the same dish, is an uprising of the organism itself against a food which does not meet its requirements; or, rather, the consequence of a deficiency already established.
Here we have an important rule for determining a wholesome diet. The foods we use must contain the indispensable elements of nutrition in due proportion; our food must be mixed, varied, and alternating. And what is here said with regard to individuals, holds good also for nations. The food-stuffs of an energetic population are up to the standard only when they are multifariously blended, and when there is a due proportion of substances belonging to the three groups mentioned above. Now, this relation between the nutrition and the physical and mental development of a people must be apparent in the history of their civilization. Where the food is insufficient, fluctuating between want and excess, uniform and undiversified, the capacity of the people for work must be inferior; their bodily strength and their mental culture must be of a low grade.
But, when we turn our eyes to the pages of history for a confirmation of this, we meet with our first real difficulty. History tells us much about deeds of heroism, bloody wars, conquests, and revolutions; of politics, manners, and customs, and even of the thoughts that have occupied the minds of nations; but of their cuisine, their bill-of-fare, history tells us nothing. And yet a history of the foods of nations would be an addition of great value to the history of human civilization. From it we should learn by what means and in what way the men of prehistoric times came into possession of their food-stuffs; and this would be a long story full of deeds and full of suffering. Fortunately, we possess other original documents besides the annals of history; documents, too, that antedate all written history, and which are no less trustworthy and unambiguous. The ground under our feet has preserved them in its strata; they rest in barrows and in caves, and in the bottom of lakes and bogs, and these primitive documents are not silent as to the food of extinct nations.
In the present status of research, the earliest authentic traces of man on earth go no further back than the age of ice, so called, and the accompanying or subsequent formation of the diluvium or drift. The relics of man dating from an earlier epoch, the upper Miocene formation, that is, the middle of the Tertiary group, which are said to have been found in France, are at least very questionable. But there have been preserved for us in caverns remains dating from the Ice Age, which tell us of the food used by man in those times. Man then inhabited Central Europe in company with the reindeer, the cave-bear, and the mammoth. He was exclusively a hunter and fisher, as is shown by the bones of animals found in his cave-dwellings. The miocene vegetation, which abounded in arboreal fruits, had disappeared during the long period of the subsequent pliocene formations, the climate of Central Europe, meanwhile, having gradually become colder. Nature supplied no fruits for the food of man. What food he got by hunting and fishing was precarious, and there were intervals of famine; for fortune does not always smile on the hunter, and the beasts of the forest are not always equally numerous. The food, too, was uniform, and not altogether adapted for man, for the flesh of wild animals lacks fat. The man of those times had not enough of the heat-producers in his food; and that he felt this want, we learn from his taste for the marrow of bones. All the long bones of animals that are found in cave-dwellings are cracked open lengthwise, in order to get out the marrow. Now, this insufficient, uniform food has its counterpart, in the low grade of culture which then prevailed, as evidenced by the mode of life, the weapons, and the tools. Man then lived isolated, without social organization; he dwelt in caverns, and his only protection against the cold was the skins of animals and the fire on the hearth. His tools were of stone, unpolished, unadorned; so rudely fashioned, that only the eye of the connoisseur can recognize in them man's handiwork.
Let us now advance a step further, and glance at a time a few thousand years nearer to our own, the period of the ancient pile-dwellings. Man then built up huts, and even villages, on piles, in the midst of lakes. These piles have been discovered, and between them, on the bed of the lake, oftentimes overlaid with peat several feet in depth, lie the monuments of those times—the waste of the house and of the kitchen. Some of these lake settlements, that near Robenhausen, in the Pfäffikonsee, for instance, were clearly destroyed by fire, and under their charred remains is buried every thing that had been contained in the eating-rooms. The lake-men, too, were hunters and fishers, and they still hunted some of the same animals as the cave-men—only the cave-bear, reindeer, and musk-ox had disappeared. They pursued fishing probably with greater success than their predecessors, for they not only employed harpoons made of bone and rein-deer horn, but had learned to make nets of flax-fibre. But they, furthermore, had begun to raise cattle; they had domesticated animals—goats, sheep, two species of swine, and two of oxen. Probably, too, they used the milk of cows, and even seem to have understood cheese-making, for twirling-sticks and perforated vessels have been found which can hardly have been used for any other process. The food-supply of the lake-men, therefore, was more assured than in the Ice Age, and also more varied; for they were, furthermore, agriculturists. They grew wheat and barley, ground the grain with querns, made porridge and bread. Remains of this porridge, as it is supposed, have been met with in pots; and flat cakes, in a charred condition, are found abundantly in the pile-dwellings of Wangen and Robenhausen. Sundry kinds of fruit, also, served for food. Dried apples and pears—wild-apples and wild-pears, it is true—blackberries, and hazel-nuts, have been taken in great numbers out of the bogs. The food of the pile-villagers was thus very abundant and diversified, and to this better nutrition answers a considerable advance in culture. The lake-man did not inhabit caverns, nor did he clothe himself in skins, as did the man of the Ice Age, but built himself wooden cabins, and wore clothes of flax. Considerable stores of flax have been found, and it is even supposed that pieces of the simple fabric have been discovered. These people lived in populous villages, and hence undoubtedly had a social organization. Their tools and weapons are of stone, it is true, but nicely polished and ornamented. Their unmistakable love of the beautiful testifies to their progress in culture.—Die Natur.