A manual of dietetics

Front matter

/Hit t v ' c/co^i/is-ZL*^

A

BY

Preface

The day of Dietetics has arrived.

Modern advances in our knowledge of the physiology of digestion have been accompanied by a like progress in the preparation of foods. The value of predigested carbo-hydrates in acute disease and malassimilation among adults, as well as children, is now being gradually realised. The digested albuminoids are making their way ; while oil emulsions have established themselves on a firm footing. The many evils of a dietary too rich in albuminoids are now being generally recognised. The time indeed is at hand when systematic lectures on Food will be a part of Medical education ; while the value of feeding in disease is admitted to be as important as the administration of medicines.

3, Henrietta Street,

Cavendish Square,

London, W.

Chap. I. — Food: Its Object

II. — Forms of Food and their Digestion, III. — Methods of Preparing Food, IV. — Condiments, ....

V. — Beverages, ....

VI. — Stimulants, ....

VII.— Fluid Foods, ....

VIII. — Preserved and Canned Foods, IX. — Prepared Foods, X. — Artificial Digestive Agents, .

PAGE 1

6 23 39 42 49 64 72 79 85

XL-

XIL-

XIIL-

XIV.-

XV.-

XVI.-

XVII. -

XVIII. -

XIX.-

XX.-

XXI. -

XXIL-

-Food -Food -Food in -Food in -Food in -Food in -Food in -Food in -Food in -Food in -Food in -Food in in in

PART II. Infancy, 96

Adolescence, . . . . .109

Adult Life, 118

Old Age, 130

Acute Disease, . . . . .137 Convalescence, .... 147

Gastric Affections, . . . .153

Struma, 157

Constipation and Diarrhoea, . . 167

Phthisis, 171

Chronic Heart and Lung Disease, . 183

Vlll CONTENTS.

PAGE

Chap. XXIII.— Food in Bright's Disease, . . . .189 XXIV. — Food in Albuminuria, . . . .195

XXV.— Food in Diabetes, 197

XXVI.— Food in Glycosuria, 20S

XXVII. — Food in Gout, 205

XXVIII.— Food in Neurosal Affections, ... 216 XXIX.— Food for Chronic Invalids, . 222

XXX.— Food in Obesity, 223

XXXI. — Food in Indigestion, 230

XXXII. — Food in Biliousness, 242

XXXIII. — Food given otherwise than by the Mouth, , 250 Conclusion, 254

MANUAL OF DIETETICS.

Chapter I. The Object Of Food

Before the days of chemistry, food was in its pre-scientific stage. Then it was mainly a question of the palate. Kings kept their cooks, and smaller personages imitated them. The cooks cooked by day and devised new dishes by night. In the present work, however, this culinary aspect of food will be subordinated to that of its scientific aspect.

Not that the cook is to be ignored, by any means. Without proper cooking, no food is palatable; and if the palate — the janitor of the stomach — be offended, no matter what is its real value, the food is useless. The palate must be consulted as well as the stomach.

Of old the palate ran riot. The Romans were both epicures and gluttons. The oysters of Britain were conveyed by relays of runners to the Roman villas. One epicure cast a slave into his fishpond to improve the flavour of his lampreys. The most absurd dishes were contrived, up to a pie of nightingales' tongues. Their tastes were not ours. Fowls were boiled in aniseed water, and served with a sauce containing aniseed, mint, mustard seeds and asafcetida. Nor were the middle ages far different. Charles V. of Germany was a notorious gourmand. Besides ordinary meats he had roasted horse, cats in jelly, lizard soup, fried frogs, etc., till his chef when asked for a new dish, could only suggest a compote of watches, — in allusion to that monarch's passion for such time-keepers.

Animals were chased because it was found that the flesh of hunted beasts was more tender and palatable than that of those killed without such preliminary preparation. Fowls were thrashed to death to fit them for the table; while one writer gave directions

" How to roast and eat a goose alive." No cruelty to an animal was too great to gratify the palate. It was merciless !

The amount eaten, too, was enormous. The Roman had five meals a day; and at great feasts when full to repletion, the stomach was emptied in order that the process of filling it might be re- commenced.

Charles V. was quite as big a glutton as he was an epicure. At a dinner of the Knights of the Golden Fleece Roger Ascham saw him make his way through sod beef, roast mutton, and baked hare, after which he fed full well on a capon. Nor did he forget to drink with it all. " He had his head in the glass five times as long as any of them, and drank no less at once than a quart of Rhine wine. " No wonder he became a gouty man.

Then views as to food varied in the widest manner. The English athlete placed his faith in rare beefsteaks and raw eggs ; while the Hindoo wrestlers trained on sweetmeats. The English farmer feeds his servants on meat in order that they may be equal to hard work; just as he adds some extra corn to the dietary of his horses when working hard. The hama of Stamboul carries incredible weights on a dietary which the English athlete would regard as utterly insufficient to support life ; and for backsheesh is grateful for a slice of melon.

Cookery-books were written by men of learning. Even Dr. Johnson, of dictionary fame, did not think the subject beneath him. " I could write a better book of cookery than has ever yet been written," he boasted. " It should be a book on philosophical principles." So important did he deem the subject that he said contemptuously: "A woman may spin, but she cannot make a good book of cookery." Dr. Kitchener, the author of " The Cook's Oracle," had a library of works devoted to food and cookery, consisting of no less than 250 volumes. It cannot then be said that the subject has not received due attention in all ages.

It is only at the present day, and from the teaching of Liebig, that food has been regarded from a scientific point of view: both as regards the hale and the sick. It is our knowledge of organic chemistry which is guiding us to a rational comprehension of the utility of food, and the requirements of the organism. Before that day the palate ruled, and tastes vary. De gustibus non disputandum !

The Burmese bury their fish until it is putrid, in order to give it the flavor they relish ; while the Sandwich Islanders like their fish so fresh that they devour fish alive as soon as caught.

THE OBJECT OF FOOD. 3

Europeans prefer a fresh egg; in Cochin China the people prefer them "high." The Israelites talked of a land of " corn and wine" and of " oil and honey." The Egyptians lived on lentiles; while the Arab exists upon dates.

The Hindoo and the Negro both delight in boiling rice and butter. Ghee is clarified butter; and the Hindoo in praising anything comestible, couches his highest praise in the phrase " as good as ghee!" On the other hand, the Gauchos of the South American pampas live solely on lean beef and water; and Sir Francis Stead has told us what power of endurance this diet gives. The Eskimo and the natives of Northern Asia eat huge quantities of fat, and drink oil. This diet is a perfect contrast with that of the desert Arab. On the burning desert little is required to maintain the body heat, and a handful of dates is sufficient for the body-needs. On the frozen Arctic wastes, fat, the strongest fuel-food, is required in considerable quantities to keep the body temperature at a point compatible with life. Cut off from farinaceous food, the Eskimo rejoices in the liver of the walrus, with its glycogen, or animal starch; but to give it a higher heating power, he eats it with slices of fat. Instinctively man has adopted the dietary suited to his needs; and the Anglo-Saxon who, on the plains of Bengal, persists in the roast beef and ale of Old England, pays the penalty of his dietary indiscretion in hepatic trouble. Blindly and darkly then, instinct has guided man in his choice of food, before the daylight of organic chemistry came to direct his path aright. Light has dispelled the darkness; but the palate is not to be dethroned. There are other things that cling to us as well as original sin ! The belief in meat is ubiquitous with the Anglo-Saxon. No one can be strong without meat, it is asserted.

" Many people seem to look upon meat almost as though it formed the only food that really nourished and supplied what is wanted for work. The physician is constantly coming across an expression of this view. Undoubtedly, a greater feeling of satiety is produced by meat than by other food. It forms a greater stay to the stomach, but this arises from the stomach constituting the seat of its digestion; and a longer time being occupied before it passes on and leaves the organ in an empty condition." (Pavy on Food and Dietetics. )

This fallacy is disproved by the fact that the Sikhs of the Punjaub are pulse-eaters. The Italian lives almost solely on maize and macaroni. The dreaded Iroquois were cultivators of maize as well as hunting Indians. The Spaniard munches his onion and dips his crust of bread in oil. The Kaffir, like the Kirghis, lives mainly on milk; as did the Cymri, when Csesar invaded Britain. The Arab has his dates. The Brahmin prefers the banana. The Hindoo, the Chinese and the Japanese, find their chief sustenance in rice, which with them takes the place of bread with us. Bread or its farinaceous equivalent is the staff of life. But " thou shalt not live by bread alone" tells that something in addition is necessary for the food of man.

What is that something ? Milk; certainly! Meat? No, emphatically No! Fat, Yes! — especially butter. Some fluid is, of course, necessary as water. Here we have all that is required. There is starch, body-fuel; there is albumen for tissue-repair in the gluten; there are earthy salts, too, especially if the bread be made of whole meal ; and then there is the fat, which partly is burnt as body-fuel, partly engaged in the building up of healthy tissue.

Let us trace the history of a mouthful of bread and butter. While it is being masticated, the saliva is brought into contact with many of the starch granules (already cracked by the heat of the oven and, not only that, but a step forward has thus been made in its solution,) and the conversion of insoluble starch into soluble sugar is begun. Then it is swallowed, when a new action is set up. The soluble grape sugar of the converted starch passes through the wall of the stomach into the gastric vesicles of the portal vein; leaving the undissolved residuum behind. The acid gastric juice next acts upon the gluten, the albuminous stroma, or framework of the mass — and by dissolving it, liberates the rest of the starch granules which had escaped the contact of the saliva. When the softened mass passes the pyloric ring, and comes into contact with the bile and the secretion of the pancreas, the most active part of the digestive act sets in. The liberated starch granules come into contact with the diastase of the pancreatic secretion, and are by it converted into soluble grape sugar; the digestion of the albuminous substances is further carried on by the trypsin; the fat is emulsionised — it is only digestion. The sugar, the dissolved albuminoids, the earthy salts, pass into the portal vein, to be dealt with by the liver; while the fat globules pass by the mouths of the lacteal s into the lymphatics. Such is the digestion of a typical mass of food; there are here, carbo-hydrates (starch and sugar), albuminoids, fat, and earthy salts. And let all the art and skill of all the cooks who ever lived, collect, cook and flavour the various edible substances of the animal and vegetable world, these are the constituents of the food of Man.

THE OBJECT OF FOOD. 5

The carbo-hydrates are the body-fuel, the surplusage being stored as fat; the albuminoids serve to repair the tissues as they wear out; the salts form the blood-salts; the fat helps to build up normal health-tissues, the excess being burnt as body-fuel. That is the real object of food!

But Nature has veiled her object. She provides an imperious palate, engrafted upon an imperative sense of hunger, and these secure the nutrition of the body. Succulent vegetables, luscious fruits, sapid flesh; such are the materials upon which the cook exercises his art; and such are the food of the savage. While milk, the natural food of the new-born, alone or in combination with (chiefly) vegetable matter, is ever acceptable. Hunger compels the individual to take food to fill the stomach; the palate guides him in his choice; if the food be simple, there is little or no temptation to indulge in excess. But when the cook's art tempts the palate, then comes in the temptation. The first temptation came through the palate — "the tree was good for food;" and Adam hearkened into the voice of Eve, and ate of the tree — and the history of human troubles began. Now, the man has hearkened to the voice of the tempter, and eats — in excess of his body-needs. He must eat to live; but that is not the true equivalent of to live to eat. The object of food is the nutrition of the body — rather than the gratification of the palate. It may be well next to examine these different constituent elements of food in fuller detail both as to their digestion and their destiny.

Chapter II. Forms Of Food— With Theik Digestion

Carbo-hydrates — Albuminoids — Fat-salts. — Liebig's great division of food into hydro-carbons, or " fu 1-food," and albuminoids, or " tissue-food/' though at one time subjected to much criticism has, in the main, stood its ground. Modern advance in physiological chemistry certainly has told us that albuminoids are oxidised in their retrograde metamorphosis and so contribute to the body-heat; we know, too, that fat is necessary to the formation of healthy tissue— as seen in the cod liver oil so much in repute for the treatment of phthisis — and so to some extent is a tissue-food, as well as a fuel-food. Even certain salts, as the malates, the citrates and the tartrates are a fuel food, in that the malic, citric and tartaric acids are oxidised, while the base (largely potash), appears in the urine as a carbonate or may be a lithate. The muscles require potash and the blood soda; why we do not yet quite know. The bones call for lime; and admitting that Liebig's view is not precisely accurate, it is true as a broad division; and is well worth bearing in mind. Why? Because since the days when Cain kept sheep, and gave way to ungovernable temper and behaved like a carnivorous brute, in his murderous instincts, man has been tempted to take meat to gratify his palate, to an extent far beyond his real tissue-needs. Man is like a steam engine in that he is a piece of mechanism in which fuel is burnt. Certainly the iron framework of the engine rusts — a slow oxidation — and needs repair; and so do the tissues of man wear out. The engine needs oil to lubricate its bearings, and sundry other matters which have to be continuously supplied to it. The animal body has other wants than merely " fuel-food" and " tissue-food," as salts for instance. The engine is a means of heating water into steam, and then utilising that steam to put wheels into motion, i. e., converting heat into motor power. When the engine is working hard it uses so much more water and fuel. When a man exerts himself he also produces more heat by increased oxidation and consumption of fuel-food. Liebig doubtless was in error in assuming that in activity the albuminoid tissues are consumed.

No more than the framework of a locomotive when ascending an incline. An engine doing hard work will need more oil for its lubrication than one doing little work; and probably will sooner have to be sent to the repairing shed. A hardworking man may wear out his muscles at a more rapid rate than an idle man. But all the same in the locomotive and the man, the framework and the tissues do not "burn/' but rust, or undergo a slower oxidation. (In forming conclusions from the amount of urea — the body ash — the perpetual and ineradicable difficulty has to be met that urea is the final soluble form of nitrogenised waste derived alike from the luxus consumption, or surplusage of albuminoid food and from effete or worn-out tissue.) Just as when the body is at rest its temperature is maintained by oxidation of hydro-carbons, so in activity the combustion is the same; only greater. Consequently the tissue-food for tissue-repair actually required is small, and more albuminoids are usually eaten than are absolutely needed. Granting that the general health of convicts deteriorates on an insufficient dietary; and that the system suffers when imperfectly fed; and that when work is hard more food, especially of the stimulating nitrogenised character is given, as the result of the teaching of experience; still the main fact remains unaffected, viz., that the actual wear and tear of the albuminous tissues is small, and can really be met by a dietary far less rich in azotised matter than that taken by most persons. Look at the lusty babies fed on " Pobbs," consisting of bread and water (with little if any milk), to be seen in any agricultural district in England. See the huge navvy " Lincolnshire bred," reared on bread and bacon, or dripping and potatoes; or the Scotchman built up on oatmeal; and we can understand that the constructive powers of the human organism can successfully contend with great difficulties. But all the same, when the navvy can procure some beefsteak he can do a harder day's work; and, I am informed, that a Highland gillie, when he shares the sportsman's repast — a dietary superior to that to which he is accustomed — waxes in vigour and energy, in an obvious and unmistakable manner ; while Dr. Furguson of Bolton has told us of the improvement in the physique of the children of the Lancashire operatives when a certain amount of milk was added to their bread and butter and tea.

Keeping in mind then Liebig's great generalisation (while admitting that it is not absolutely correct as to minutiae) we find the food of man ranging itself into three main divisions —

1. Carbo-hydrates;

2. Albuminoids;

3. Fat;

With a small sub-class —

4. Salts.

Water too is essential to the body, but it cannot exactly be classed asa" Food."

Carbo-hydrates. — Under the term Carbo-hydrates are classed the starchy, or farinaceous, or amyloid (as we choose an English, a Latin, or a Greek term), and the saccharine elements of our food.

Starch consists of Carbon, Nitrogen and Oxygen (having the formula C6H10Os) and is found in all the cereals; especially in those used as the food of man, wheat, oats, barley, maize and rye; it is also found in the pulse tribe, or legumes, as the pea, bean, lentil and the haricot bean, as also the dahl of India; also in rice, buckwheat, sago, tapioca and arrowroot, and the quino of Peru. It abounds in the potato, and other roots (which contain the germs of the new plant), in carrots, parsnips and turnips which first produce a root, from which again a seed -bearing stem is developed; and is part of the unripe fruit, which becomes sweet as the starch is changed or converted into sugar.

Starch is the food of the seedling plant. To take the case of a grain of any cereal, it contains starch, albuminoid matter, and earthy salts; while oats and maize also contain notable quantities of fat. When the plant germinates the starch is converted into sugar, (as the baby plant requires it) by the action of the diastase (an albuminous ferment), as the seedling grows. Insoluble starch is converted into soluble sugar in the grain; just as it is in the human mouth. The plant stores up food for its young; and that food man takes for his own use. Why does the store of plant food take the form of insoluble starch? Because if soluble it would be liable to be dissolved by water; and after rain the grain field would be barren, because the food elements were washed away in solution. Insoluble starch can be stored.

A rapid germination is artificially set up by the process of " malting"; which will occupy our attention further on.

When man ate uncooked grain, as he did at an early period (as the worn molars of graminivorous men still tell us when dug up), he ground it slowly under his teeth; and during this time the starch came in contact with the saliva, which by its diastase converted this starch into soluble dextrine (with the starch formula) and grape sugar (C5H1206,H20). The action was exercised upon the outside of the starch granule; the remainder passing on through the stomach till it reached the diastase of the pancreatic secretion, when it became fully dissolved. (All starch granules however are not equally acted upon, and where much starch food is taken a certain quantity of them are to be found in the faeces.)

When man came first to crush and then to grind and cook his food, a new departure took place. The toil of grinding his grain was done for him in a less laborious manner. Disintegration took place in the mill. He could eat faster. But if no other change had gone on, this might have been a very questionable advantage; for it would have had the result of filling his stomach with insoluble starch granules (a fertile source of indigestion). The effect of heat upon the starch granule is to crack it and thus to form a channel by which the saliva could reach the interior; an important matter. But another change goes on of which the knowledge is far less general. The starch is converted largely into soluble dextrine. (When a portion of well -baked flour is subjected to the iodine test, the conversion of the starch is readily seen.) Consequently the farina is speedily transformed into soluble matters by the saliva. The existing dextrine is carried forward to grape sugar; while the remaining starch is largely changed into dextrine. Such then is the effect of the act of- cooking upon the starch granule. Grinding and cooking lessen the labor of the jaws and the salivary glands.*

Disintegration and solution constitute the digestive act. The conversion of starch into grape sugar is brought about by the salivary diastase (an albuminous body whose formula has not yet been determined), by a process of hydration; and grape. sugar has the formula) C6H1206H20), i.e., some water has been introduced into the molecule. The saliva is operative in the mouth and in the gullet, and also in the stomach until it becomes distinctly acid. The soluble grape-sugar passes through the wall of the stomach into the blood.

This removal of much of the starchy matter of the food allows the stomach to act upon the other constituents. When food is hastily swallowed, our mastication is imperfect from bad teeth, the

* Grain and bread crusts developed the jaws and teeth. The soft food now in vogue for infants is one factor in the prevailing dental decay.

•

stomach is hampered and embarrassed by quantities of unchanged starch, and its digestion is slow and painful.

When the stomach becomes distinctly acid, the conversion of starch is arrested. When the stomach has done its work and gastric digestion is complete the acidity seems pretty much exhausted, and the chyme (as the pultaceous mass is termed) finds its way into the duodenum, where it becomes mixed with the bile and the pancreatic secretion. In this alkaline medium the pancreatic diastase comes into play, and the transformation of insoluble starch into soluble dextrine and grape-sugar re-commences. As the more or less disintegrated or denuded starch granules pass along the small intestine they become fully dissolved into grape-sugar which passes into the blood of the portal vein.

Such then is the digestion of starch. But before following up the history of grape sugar in the body, it will be well to consider the different forms of sugar. Sugar may be divided into crystalline or cane sugar (CiaH19On) and glucose or grape sugar. The crystalline sugar is the object of the sugar-baker; and the faeces of sugar boiling, treacle or molasses, are the non-crystallisable sugar. On the other hand non-crystallisable, or invert sugar, otherwise levulose, is the object of the manufacturer who supplies the brewer with substitutes for malt. Crystalline sugar is found in the sugar cane, the beet root, other roots, the maple and the sugar grass. Both are sweet to the taste; crystalline sugar being more intensely sweet, while the flavour of non-crystalline sugar is finer to most palates. As sugar is the food of the seedling plant, so sugar is found in all young shoots (notably in those of the briar and the grasses, as all rural children know).

" Although cane sugar requires no digestion to fit it for absorption it may be considered probably that it undergoes conversion into grape-sugar, certainly in part, if not wholly before leaving the alimentary canal. If cane sugar be introduced into one of the vessels of the general circulation, it passes off from the system without being utilised and escapes, still in the form of cane sugar in the urine.1

If, however, cane sugar be introduced into the alimentary canal beyond the capacity, say, for subsequent assimilation, sugar similarly passes off with the urine; but now in the form of grape sugar instead of cane sugar." (Pavy.)

When the soluble grape sugar — whether derived from starchy or saccharine elements of our food it matters not — passes into the portal vein, it flows thereby to the liver. Here it is dehydrated, or turned back into glycogen, or animal starch (C5H10O5). In this insoluble form once more it can be stored for the body needs. Carbo-hydrates then furnish the glycogen or body-store of fuel in the liver. The liver stores up from each meal so much glycogen; and gives it off as required; otherwise life would be only one dreary meal. (Any disturbance in these glycogenic arrangements leads to the presence of sugar in the urine. These disturbances may extend from the mere presence of sugar in the water after a meal, when the dehydrating power of the liver cannot keep pace with the diastatic activity, up to the dread disease diabetes.)

The insoluble store of glycogen is given off as required in the form of soluble grape sugar; which is probably burnt up as lactic acid (C6H1206) in union with soda, as lactate of soda. (Muscles have their little stores of glycogen; the muscles of the embryo being especially rich in it.)

Such then is the history of the Carbo-hydrates, our great " fuel-food"; corresponding to the coal in the tender of the locomotive. The surplusage of grape sugar forms the fat, or adipose tissue of the body: a further reserve of " fuel-food. " The store of glycogen in the liver is readily got at, and so we may liken it to the coal-scuttle by the fireside, while the fat deposit is the coal cellar. In some individuals it is spread over the body generally; while in others the omentum and parietes of the abdominal muscles are its chief seats.

In some animals, as the pig for instance, the fat is wide-spread and general, while in the camel the fat is stored in the hump, and in the codfish the liver is the seat of the storage of fat, as well as of glycogen.

This grape sugar is the natural body fuel, and where it is burnt up, the organism perishes of exhaustion; whether in starvation or acute disease. This matter will be further discussed when the dietetic treatment of exhaustion is given further on.

Albuminoids. — Albumen is a complex body notably containing nitrogen. This is the cardinal matter which fits it for the non-oxidisable framework of the body in which the combustible hydro-carbons are burnt. " Of all the elements of the animal body, nitrogen has the feeblest attraction for oxygen; and, what is still more remarkable, it deprives all combustible elements with which it combines, to a greater or less extent, of the powTer of combining with oxygen, that is, of undergoing combustion." (Liebig.)

By virtue of this nitrogen-factor then, the albuminous tissues are prevented from the body-combustion extending to them. Like the framework of the locomotive they rust but do not burn. Their composition is as follows:

02,H,N16CS3S, From this we can see that they differ from the hydro-carbons in the fact that they contain some sulphur as well as a distinct amount of nitrogen. The egg from which the living bird is developed contains albumen, some fat, and water. Probably the shell furnishes the lime. White of egg is typical albumen. Albumen is found in the muscles or flesh of animals; it is found in milk, as caseine, and in all seeds, notably the pulse tribe, whose seeds are rich in vegetable caseine. A certain proportion is found in cereals as the gluten of wheat, for instance.