The relation of food to health and premature death

Front matter

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THE

Preface To Second Edition

Since the first issue of this book there has not beerwsufficient new facts developed to warrant extensive changes in the second edition. The most extensive addition is that on rheumatism. Other slight changes modify the text somewhat, but are mainly typographical.

The favor accorded the first edition, and the good it is doing, is highly gratifying.

Contents

Chapter. Pa S eS '

I. Introduction - 1-1 ^

II. Digestive Organs and Processes of

Chapter II. Digestive Organs, And The Processes Of Digestion

"Doctor, in beginning the study of any subject, it is of course very important to start right."

"That is true, and if we are to understand the source of health as well as disease, we must know something about the digestive organs and how they work to keep us well, and under what circumstances they will not, or can not work, and thus allow us to get sick."

"A great many people don't understand what is meant by digestion."

' "Digestion is the process by which the various particles of food we eat are dissolved and changed by the digestive secretions and processes into suitable elements for the various uses of the body."

"Are the particles taken into and absorbed by the system made very fine?"

"Yes, the particles that are absorbed are so fine that they must be magnified several hundred times before they can be seen by the naked eye."

"This is very interesting, Doctor, where does the process begin?"

"It commences where a great many kinds of trouble begin."

"That must be in the mouth?"

"Yes, in the mouth and in the kitchen, and unfortunately, most people in this, as in other things, use their mouths and kitchens much but not well."

"What do you mean by that?"

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FUNCTIONS OF SALIVA 15

"That they talk without thinking, eat without chewing, cook without knowing how, and eat more than they eat properly."

"That is because they don't know how to do any better?"

"That's a charitable view and no doubt true in part."

"At any rate one is astonished, at how little people know about living and that is true even of the educated classes."

"Yes it is, A good many people would dispense with their mouths for eating if they could, and shovel their food into their stomachs just as they would load a wagon with hay. When they get sick, they charge it to anything or everything except their own folly."

"Then the great fault is in eating too fast?"

"Well, as already stated, digestion is first of all a process of dissolving, and a good many people treat their stomachs as though they had better teeth in them than in their mouths. It is time for people to learn that they only have one set of teeth, and that if they continually impose on their stomachs, by compelling them to do the work that should be done by the teeth, sooner or later, their stomachs will get stubborn and not work at all."

"Yes, Doctor, but you forget, don't you, that many kinds of food are ground before they reach the mouth?"

"That would seem to be a good point, but somehow the creator of man did not anticipate mills, and consequently, arranged an important process of digestion in connection with the uses of the teeth, which cannot be avoided without positive injury."

"Then there is no safe way of cheating the teeth out of their grinding business?'

"None whatever."

16 MOUTH DIGESTION

"What is the important process that you have just mentioned ?"

"No doubt, you have noticed that when you chew anything, your mouth is soon filled with a slippery ropy fluid, usually known as saliva."

"Yes, where does it come from?"

"It is a secretion that comes from glands within and adjoining the mouth each of which has a tube draining into the mouth."

"Have these glands names."

"Yes, the principal ones are known as parotid, submaxillary and sublingual glands and there are small glands scattered through the lining membranes of the mouth and tongue. These are called buccal (mucous and serous) glands."

"Do they all secrete the same kind of fluid?"

"Well, it is all a digestive agent, though the character of the secretion of each is different?"

What are the various uses or saliva?"

"It was formerly supposed that the saliva had no other use than to moisten the food, and no doubt every one has noticed that as soon as they commence to chew anything, the saliva commences to flow; for that reason, it appeared that the saliva was only intended to make the food soft so it could be swallowed easily, but with the aid of modern chemistry, we have learned that saliva is a digestive agent, which must be mixed with the food during the grinding of the same by the teeth."

"What is the nature of the secretion?"

"It is an alkaline solvent that dissolves that part of the food known as starch, gum, pectose and similar substances."

"In what is an alkali different from an acid?"

-

FUNCTIONS OF SALIVA 17

* 'Probably, the nearest we could describe it would be to say that it is the opposite of acid. If we mix them in proper proportions, according to the strength of each, both will become inert."

"Then digestion of all foods containing starch begins in the mouth? "

"It begins there if the saliva be mixed with the food but the fact that so many people swallow their food without chewing it, especially all soft foods, such as warm bread, mashed potatoes, pudding, oatmeal and all similar foods, there is not ordinarily sufficient saliva added to digest any quantity worthy of notice."

"Then the old saw, 'who eats slowly lives long' must be true."

"It is."

"Has the saliva any effect on foods other than the starches?"

"Not as a digestive agent, but it aids in keeping the particles of food that are crushed by the teeth from adhering together."

"How much saliva is ordinarily secreted in a day?"

"Those who have carefully estimated it, say that eight to ten ounces are daily secreted."

"That would hardly include tobacco and gum chewers, would it?'

"No, chewing tobacco is a perverted use, and tobacco chewers have saliva with which to bathe a considerable portion of the earth but very little for their food."

"Of what temperature does the saliva act on starch?"

"At 103° to 112° F. It does not act below 85° F. to any extent, nor over 168° F."

"Then moderate temperature is an important thing indigestion?"

18 FOUL MOUTHS

"Yes, this explains part of the ill effects of ices and very hot drinks.''

"What is the other part?"

"Direct damage to the mucous membrane."

"is there anything else about the mouth that aids digestion?"

"Nothing that aids it, but something that doesn't aid it."

"What is that?"

"Filth. Some people keep their mouths like garbage boxes. They allow all kinds of food to lodge and decay until it even rots their teeth, and then they have a mouth tainted with decaying food and decomposing bones, which is a harbor for the various kinds of bacteria."

"What harm does this do?"

"When food is eaten, these foul accumulations and bacte/ia are carried to the stomach, and no doubt are often great factors in disturbing the stomach and general system, and one of the sights calculated to make one pity the human race is to see persons .cut holes in their flesh to make themselves beautiful with jewelry and yet carry a mouth and teeth coated with putrid matter so offensive in odor that it is disagreeable to be near them."

"What becomes of food when it leaves the mouth?"

"It passes down a tube called the oesophagus (gullet) into the stomach."

"Do people understand how their stomachs are constructed?"

"No, a great many people suppose their stomachs are copper lined, or at least their habits lead one to that conclusion."

"Why do you say that?"

"Because they have no regard for their stomachs and give themselves no concern as to the character or quantity of what they put in them."

STRUCTURE OF STOMACH 19

"In what particular?"

"It is not an uncommon thing to see people eat soup scalding hot and then drink ice water to cool it. Others make a catch basin of their stomachs and pour in several gallons of beer or large quantities of stronger liquors.' '

" There are but few who do not use mustard, pepper , horseradish and other intense irritants, while those who are continually taking poisonous drugs are legion. This is not all, the stomach is not supposed to rebel no matter how coarse or tough the food, nor how incompatible the mixtures that ignorance pours into it, and as a result of all this, if the aches, pains, diseases, misery and deaths could be measured by volume they would make a pyramid from the earth to Jupiter."

"Suppose you tell us something about the stomach, doctor?"

"I can do that best by first showing you a photograph of it. (See page 20 for illustration.) It is generally described as an irregular shaped sack or pouch, and will hold in normal condition from two up to three and a half pints, although in one case the stomach of a grown person was known to hold only a half pint. Abnormal size is very common, because the majority of the people use their stomachs as a receptacle for the most outlandish collection of indigestible material which a pampered civilization can supply. This stretches them so that they are made to retain several gallons of liquid and food under which the system groans with the weight of its torture. The modern stomach exposed to view looks much like a fourth of July balloon. The inside of the stomach is lined with mucous membrane, very similar to that of the mouth. This is arranged in many folds running lengthwise. If the membrane be examined by a microscope, innumerable pits are seen. These pits indicate the pres* ence of gastric glands."

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A, stomach. B, pyloric end of stomach. C, liver turned up to expose stomach. D, large intestine. E, rectum. F, annus.

EXPERIMENTS IN DIGESTION 21

"Do the gastric glands perform an important part in digestion? "

"They do, for they secrete what is commonly known as gastric juice.' '

"Are there other glands in the stomach?"

"Yes, mucous-forming cells that secrete mucus."

"Is the gastric juice anything like saliva?"

"Not in the least, for the gastric juice is acid and the saliva alkaline."

"Then it is the acid that dissolves the food?"

"That depends upon the kind of food you mean. Properly speaking, it is not the acid alone, but the secretion of acid and a substance called pepsin, acting together, that dissolves tissue forming foods, but not starch. There is another substance in the gastric juice called rennet. This is also called a milk-curdling ferment."

"How did they ever find out anything about what was in the stomach, and what goes on in the process of digestion?"

"Well, not much was known prior to 1822."

"What was discovered at that time?"

"That was the time when a man by the name of Alexis Saint Martin had his stomach accidently torn open by the discharge of a musket."

"What was the wound like?"

"The front part of the sixth rib was blown away, the lung and diaphragm torn; but after a long convalesence he recovered except that there was a large fistulous opening into the stomach. This at first had to be bandaged, but after a time a portion of the mucous membrane of the stomach prolapsed until it hung down over the opening, thus acting as a sort of a curtain to the stomach,"

"That was remarkable."

24 CHEMICAL PROCESS OF DIGESTION

''Yes, great harm, and such ailments as cramps, colic, diarrhoea and catarrh of the gall bladder, causing gall stones, are common results from coarse substances passing through the stomach into the bowels."

"Has there been any extensive investigation made about digestion since that of Dr. Beaumont?"

''Yes, investigations have been going on almost constantly ever since, and have been much aided by what we might properly term Modern Chemistry. A German physiologist in 1831, discovered that saliva digests starch, i. e., turns it into grape sugar, sometimes termed maltose. Since then, repeated experiments have been made upon man and animals. Thousands of tests have been made by siphoning the gastric juice and partly digested food from the stomach, and also almost every conceivable test has been made on dogs and other animals."

"Doctor, you say saliva is alkaline while the gastric juice is acid. A while ago you stated that these were antagonistic and that the alkali neutralized the acid. Now, how can digestion be carried on by two elements directly opposite to each other, one neutralizing or destroying the effect of the other?"

"That is a good question, and a right understanding of the answer would clear up many of the doubts and difficulties concerning food, or rather our diet. In the first place, it would be well to remember that the saliva makes its appearance in the mouth; that it has great effect on the digestion of starch, or starchy food; that it should be mixed with the starchy foods as thoroughly as possible. Then, when the food reaches the stomach, the gastric juice only begins to flow. It will thus be seen that there is considerable time for the digestion of the starch before any quantity of gastric juice has been se-

CHEMICAL PROCESS OF DIGESTION 25

creted in the stomach, or to put it another way, the starch digestion begins in the mouth and continues after reaching the stomach until the stomach has secreted a sufficient quantity of the acid gastric juice to counteract the effect of the alkaline saliva which the food received in the mouth. Ordinarily, it would require from 15 minutes to a half hour for the stomach to become sufficiently acid to neutralize the amount of saliva that ought to be mixed with the food during its mastication before it reaches the stomach. As the stomach gradually becomes more and more acid, the starch digestion gradually lessens until it entirely ceases. Then the action of the stomach walls becomes quite intense, and gastric digestion properly begins. "

"What do you mean by gastric digestion?" "I have tried to make it plain that the saliva has no solvent action upon proteid or tissue forming foods. It is this class of foods that are dissolved or at least should be, in the stomach, by the secretions therein."

"What class of food do you call starches?" "Generally speaking, all the vegetables with the possible exception of peas and beans, are essentially starch, and even peas and beans contain a per cent of that substance. The foods acted upon in the stomach are lean meats of every kind, eggs, milk, cheese, fish, and the vegetable casein in peas and beans and the gluten found in wheat and in other cereals."

"Is digestion completed in the stomach?" "Not by any means. By far the most important part takes place below the stomach — in the small intestines."

"Then, according to the statement you make, the stomach is not of much use, and knowing something of

26 REMOVAL OF STOMACHS FROM DOGS

the trouble and pain it gives it looks as though we were constructed on immature plans.' '

"Not at all. The stomach has its use and a most important one, although Czerney in 1876, at Heidelburg, Germany, removed the entire stomach of two dogs. No mention is made as to the effect on one of the dogs, but the other lived from 1876 to 1882, when he was killed for the purpose of making an examination as to his condition. At the time his stomach was removed, the dog weighed 5,850 grams (22 lbs.), a month after he weighed considerably less, but during the year his weight increased to 7,000 grams (29 lbs.)"

"Has any person ever lived with the stomach removed?"

. "A few have, and several where the pyloric end of the stomach (i. e. the end on right side) has been cut out and the intestines sewed to the stomach. Such operations have seldom been successful, but it is probably due to the fact that they have never been made until the patient was almost dead of some malignant disease, such as cancer or ulcer."

"You have made no mention, Doctor, of fats. What action has the gastric juice or saliva on them?"

"Until within a few years it was supposed that the gastric juice had no effect whatever upon the fats, but modern investigation has changed that view somewhat, and it is now understood that the gastric juice is capable of breaking down or disintegrating fat cells thereby setting the fat particles or globules free. This, no doubt, is a great aid to intestinal digestion. It is also believed that the fat is to some extent changed into fatty acids and glycerine by the gastric juice."

"Has the gastric juice any other action?"

EFFECTS OF GASTRIC JUICE ON FATS 27

"It converts cane sugar into grape sugar, thus preparing it for absorption into the system."

"Is there anything besides starch that is not greatly acted upon by the gastric juice?"

"Yes, cellulose."

"Where is it digested?"

"It is digested somewhere in the apparatus of the lower animals, but nowhere in man; in fact, it keeps starch from digesting, because starch is encased in small cellulose cells, and unless the cells are ruptured by cooking or by mastication, starchy cereals and vegetables are almost wholly indigestible."

"How long does food ordinarily remain in the stomach?"

"From one to four hours, frequently longer."

"What are the modifying conditions?"

"Much depends on the kind of food, upon the cooking, and the mixture of different kinds of foods."

"Doctor, that is not plain to me, will you give examples?"

"Yes, meat and tough vegetables, like peas and beans, require longer time for digestion than something that is easily dissolved, like the white of an egg. Then as to cooking, the longer meats are cooked, especially if roasted or fried, the harder and more insoluble they become, as heat coagulates, that is, makes the albumen in meat more solid."

"Is there anything else that makes meat difficult of digestion?"

"Yes, being saturated with fat, because the gastric juice of the stomach has only a limited effect on fat, and if eggs or lean meat be fried or saturated with it, the particles might aptly be termed encased, and could only be acted on to a limited extent, if at all, by the digestive

28 CONDITIONS RETARDING DiGESTION

agents of the stomach. This is the reason why fried lean meat is so hard to digest.' '

"Is this all that determines the period of digestion ?"

"No, there are many other things. The fineness of the particles of food has much to do with it, and it will not require any labor to demonstrate that a particle, say the size of a pea or bean would not be so quickly dissolved, if it be dissolved at all, as a particle as small as very fine flour, so that the length of time food should require for digestion depends much upon how finely it is masticated or artificially divided, and this applies equally to both meats and starches. Another factor is the amount of acid in the stomach.' '

"How does that affect the duration of digestion?"

"Some persons secrete very" little acid, and are almost wholly unable to digest meats ; others have such strong acid secretions that they digest meats very quickly, but that very fact might in a measure prevent starchy foods from being dissolved by the saliva, so that the kind of food and the amount of acid in the stomach are both elements affecting the period of digestion."

"Is this all, doctor?"

"No; perhaps one of the most important of all is the demand of the system for food."

"How does this affect digestion?"

"Well, if the system has previously been supplied with more food than it can use, nature has some way of protecting herself by not adding to the burden already carried. Of course, if the intestines are loaded with matter and their action slow, the food would not be quickly drawn downward. It is believed that when the system is clogged or there is an excessive accumulation of matter in the bowels, that the stomach must necessarily be in sympathy, and it sometimes happens that

TIME REQUIRED FOR DIFFERENT FOODS 29

foods remaining too long in the stomach and decaying there is the first symptom pointing to the fact that the digestive organs have been overloaded and that there is no demand for food. ,,

"Some people say that the amount of drinks or fluid taken into the stomach has much to do with the duration of digestion.' '

"That is true. If the digestive juices are greatly diluted they must necessarily be much less active than if they have their full strength."

"What about the temperature of the fluids taken into the stomach?"

"It also influences digestion, from the fact that the temperature of the stomach must be maintained at about the normal heat of the body. If cold drinks be poured into the stomach, as a matter of course, digestion will be delayed until the stomach can be re-warmed."

"Do individual peculiarities have much to do with the time required for digestion of food?"

"Yes, some people have very active stomachs but yet have inherited some antagonistic tendency to certain foods"

"I have often heard people say that when people are in serious trouble that they were likely to suffer from indigestion, why is this?"

"Well, anything which affects the nervous system and in that way disturbs circulation, will affect digestion."

"What is the theory of this, Doctor?"

"It is because the stomach requires a large supply of blood, and if the blood from any cause is in excess in other organs the supply of the stomach will necessarily be diminished. Great mental excitement keeps the flow of blood to the head instead of the stomach, and the same may be said of every vigorous exercise. There is still

30 STRUCTURE OF INTESTINES

another cause for the various periods required for digesting the different foods, that is, their chemical effect on each other. To illustrate, tea contains a large amount of tanic acid. If strong tea should be drunk after eating the white of eggs, the tanic acid of the tea would precipitate the albumen of the eggs and make it entirely indigestible. This is about the same process as that of tanning leather"

"Then you don't attach much importance to statements that certain articles of food are digestible in a certain time?"

"No, although something like an ordinary average might be estimated, for instance, well-done meat should ordinarily be digested in four or five hours, or six at the most, although sometimes it is never digested. Meat properly cooked should be digested in about 3 hours, and experiments with raw meat show that under fair conditions, it will be digested in 2J hours."

"Then according to that, cooking meat makes it more indigestible?"

"As a general rule, it does, and as it is ordinarily cooked, it makes it much more so. The same may be said of eggs. Raw eggs could be digested in about two hours; hard fried eggs, if at all, in four to six hours."

"How about vegetables?"

"Peas and beans being very tough require three to four hours. Ordinary bread, if good, about 2J hours."

"Do liquids require much time for digestion?"

"Water or fats and oils taken on an empty stomach would not ordinarily remain in the stomach but a few minutes."

"How about milk?"

"Milk is taken as a liquid but it becomes a semi-solid in the stomach, and requires one-half to two hours for

STRUCTURE OF INTESTINES 31

digestion. Of course, as already explained, these estimates are only mere outlines which are varied by many circumstances."

"When digestion begins, does the food leave the stomach as fast as digested?"

"No, although at intervals small amounts of dissolved food are ejected from the stomach, but the greater portion of it remains in the stomach until digestion has been sufficiently completed to allow the food to pass into the intestines."

"Then according to your explanation, the stomach is a sort of a reservoir, in which the food is prepared for further changes in the intestines."

"Yes, it might be called something of a dissolving vat."

"Why is this?"

"Well, the intestines are much more susceptible to foreign substances than the stomach."

"I don't understand what you mean?"

"I will explain; the stomach is an organ of considerable size, while the intestines have smaller diameter and greater length."

"About how long?"

"The small intestines about twenty feet or more, the large intestines about five feet'. Where the intestines join the stomach is called pylorus. Where it joins the large intestines, ileo-caecal valve."

"What is their general structure like?"

"It is a small tube containing muscular layers running lengthwise and also around the intestines. The blood vessels and glands are very numerous. The inside of the intestine- being lined with a mucous membrane similar to that of the stomach, but in the stomach the folds run lengthwise while in the intestines they are crosswise,"

32 PANCREATIC DIGESTION

"What is the principal agent of intestinal digestion?" "Pancreatic juice, which is secreted by the pancreas."

"Then according to that, the pancreas is the most important of the digestive organs?"

"Well, the digestive organs act as a unit, each being essential, although the pancreas furnishes the most indispensable part of the digestive fluids, because digestion can go on in the intestines if the food be fine enough, even though there be no preparation made in the stomach, or by the mouth.

"What kind of an organ is the pancreas?"

"It is a long, narrow gland of reddish cream color, but of course the color varies according; to circumstances."

"Where is it located?"

"It lies behind the stomach in the rear wall of the abdomen."

"In what way is it connected with other organs?"

"It has two tubes or ducts, emptying into the intestines three or four inches below the lower end of the stomach."

"Doctor, you haven't explained the general character

of the pancreatic juice?"

"It is an alkaline fluid containing many chemical elements."

"How do these elements act in furthering the processes of digestion."

"The pancreatic juice has three distinct properties. It dissolves all preteid foods, such as meat and eggs, also has a very active solvent, which quickly digests starch and it has still another element which splits up or decomposes the fats, splitting them up into extremely small particles making a creamy substance closely resembling soap."

BILE 33

"Is there any other digestive agent besides what you have already mentioned?"

"Yes, there are others. The one most universally known but probably the least important, is bile."

"I have often heard people speak of having bile on the stomach, is this true?"

"Not ordinarily at least, the bile duct from the liver or gall bladder empties into the intestines several inches below the stomach, and it is only when the proceedings of nature are reversed as in cases of extreme vomiting, that the bile is brought up through the stomach."

"Of what use is bile in digestion?"

"The uses of the bile are still a subject of more or less dispute, although it is generally understood that the bile is a very important factor, in connection with the pancreatic juice, in preparing fats for absorption. A number of experiments have been made upon the digestion of animals without bile, and it was found that .a large per cent of the fats were not absorbed. This is said to be true also in jaundice where the flow of bile is obstructed or in some way deficient."

"Has it any other uses?"

"Being strongly alkaline, it arrests the action of the stomach juices and aids in preparing the food as it comes from the stomach for pancreatic digestion; this being an entirely different process from that carried on in the stomach. Bile will dissolve small quantities of fats, and has long been used to remove grease stains from delicately colored fabrics, but its action alone without the pancreatic juice is not very marked."

"What other uses has the bile?"

"It is claimed that it will to a certain extent prevent abnormal fermentations or decay of the food in the in-

34 INTESTINAL GLANDS

testines and there is no doubt but what bile acts as a laxative in the bowels. It also acts as an antidote to poison known as nicotine which is one of the active principles of tobacco. Numerous experiments have demonstrated the fact that it is about the only known substance which increases the flow of bile, although various drugs in a measure accomplish the same result by setting up an activity of the bowels; these are known as cathartics."

"Is there any other secretions found in the intestines that affect digestion ?"

"There are numerous small glands throughout the intestinal canal. These secrete an alkaline fluid but so far as has yet been determined they have no other use except to convert starches into sugar and perhaps aid in keeping the contents of the intestines from becoming excessively acid through fermentative processes."

"I don't see what is to be gained by all this talk about digestive processes in the intestines?"

'•Then you don't care to know how to keep alive. That is why a good many people don't live, they merely exist, at least they must have constant assistance from their doctor."

"Then, what is to be learned by this?"

"First, that there is a limit to the size of the lumps — the coarseness of the food that can be properly disposed of by the stomach."