(narrates the author's adventures in search of health, and his conclusions as to what to eat.)

students of the body assure us that every particle of matter which composes it is changed in the course of seven years. it is obvious that everything that is a part of the body has at some time to be taken in as food; so the problem of our diet today is the problem of what our body shall consist of seven years from now, and probably a great deal sooner.

i begin this discussion by telling my own personal experiences with food. i am not going to recommend my diet for anyone else; because one of the first things i have to say about the subject is that every human individual is a separate diet problem. but i am going to try to establish a few principles for your guidance, and more especially to point out the commonest mistakes. i tell about my own mistakes, because it happens that i know them more intimately.

i was brought up in the south, where it is the custom of people to give a great deal of time and thought to the subject of eating. among the people i knew it was always taken for granted that there should be at least one person in the kitchen devoting all her time to the preparing of delicious things for the family to eat. this person was generally a negress, and, needless to say, she knew nothing about the chemistry of foods, nothing about their constituents or nutritive qualities. all she knew was about their taste; she had been trained to prepare them in ways that tasted best, and was continually being advised and exhorted and sometimes scolded by the ladies of the family on this subject. at the table the family and the guests never failed to talk about the food and its taste, and not infrequently the cook would be behind the door listening to their comments; or else she would wait until after the meal, for the report which somebody would bring her.

in addition to this, the ladies of the family were skilled in what is called "fancy cooking." they did not bother with the meats and vegetables, but they mixed batter cakes, and made all kinds of elaborate desserts, and exchanged these treasures and the recipes for them with other ladies in the neighborhood. in addition to this, there were certain periods of the week and of the year especially devoted to the preparing and consuming of great quantities of foods. once every seven days the members of the family expressed their worship of their creator by eating twice as much as usual; and at another time they celebrated the birth of their redeemer by overeating systematically for a period of two or three weeks. needless to say, of course, the children brought up in such an environment all had large appetites and large stomachs, and their susceptibility to illness was recognized by the setting apart for them of a whole classification of troubles—"children's diseases," they were called. in addition to children's diseases, there were coughs and colds and sore throats and pains in the stomach and constipation and diarrhea, which the children shared with their adults.

i had a little more than my share of all these troubles. always a doctor would be sent for, and always he was wise and impressive, and always i was impressed. he gave me some pills or a bottle of liquid, a teaspoonful every two hours, or something like that—i can hear the teaspoon rattle in the glass as i write. i had a profound respect for each and every one of those doctors. he was wisdom walking about in trousers, and whenever he came, i knew that i was going to get well; and i did, which proved the case completely.

then i grew up, and at the age of eighteen or nineteen became possessed of a desire for knowledge, and took to reading and studying literally every minute of the day and a good part of the night. i seldom let myself go to sleep before two o'clock in the morning, and was always up by seven and ready for work again. i did this for ten years or so, until nature brought me to a complete stop. during these ten years i was a regular experiment station in health; that is, i had every kind of common ailment, and had it over and over again, so that i could try all the ways of curing it, or failing to cure it, and keep on trying until i was sure, one way or the other. i came recently upon a wonderful saying by john burroughs, which will be appreciated by every author. "this writing is an unnatural business. it makes your head hot and your feet cold, and it stops the digesting of your food."

this trouble with my digestion began when i was writing my second novel, camping out on a lonely island at the foot of lake ontario. i went to see a doctor in a nearby town, and he talked learnedly about dyspepsia. the cause of it, he said, was failure of the stomach to secrete enough pepsin, and the remedy was to take artificial pepsin, obtained from the stomach of a pig. he gave me this pig-pepsin in a bottle of red liquid, and i religiously took some after each meal. it helped for a time; but then i noticed that it helped less and less. i got so that a simple meal of cold meat and boiled potatoes would stay in my stomach for hours, in spite of any amount of the pig-pepsin; i would lie about in misery, because i wanted to work, and my accursed stomach would not let me.

all the time, of course, i was using my mind on this problem, groping for causes. i found that the trouble was worse if i worked immediately after eating. i found also that it was worse when i was writing books. when i got sufficiently desperate, i would stop writing books and go off on a hunting trip. i would tramp twenty miles a day over the mountains, looking for deer, and i would come back at night too tired to think, and in a week or two every trace of my trouble would be gone. so my life regimen came to be—first the writing of a book, and then a hunting trip to get over the effects of it. but as time went on, alas, i noticed that the recuperation was more slow and less certain. the working times grew shorter, and the hunting times grew longer, until finally i had got to a point where i couldn't work at all; i would go to pieces in a few days if i tried it. it was apparently the end of my stomach, and the end of my sleeping, and the end of my writing books. my teeth were decaying, not merely outside but inside; i would have abscesses, and most frightful agonies to endure. i would lie awake all night, and it would seem to me that i could feel my body going to pieces—an extremely depressing sensation!

i had been trying experiments all this time. i had been going to one doctor after another, and had got to realize that the doctors only treated symptoms; they treated the "diseases" when they appeared—but nobody ever told you how to keep the "diseases" from appearing. why could there not be a doctor who would look you over thoroughly, and tell you everything that was wrong with you, and how to set it right? a doctor who would tell you exactly how to live, so that you might keep well all the time! i was studying economics, and becoming suspicious of my fellow man; it occurred to me that possibly it might be embarrassing to a doctor, if he cured all his patients, and taught them how to live, so that none of them would ever have to come to him again. it occurred to me that possibly this might be the reason why "preventive medicine," constructive health work, was getting so little attention from the medical fraternity.

two things that plagued me were headache and constipation, and they were obviously related. for constipation, the world had one simple remedy; you "took something" every night or every morning, and thought no more about it. my stout and amiable grandmother had drunk a glass of hunyadi water every morning for the last thirty or forty years, and that she finally died of "fatty degeneration of the heart" was not connected with this in the mind of anyone who knew her. as for the headaches, people would tell you this, that, and the other remedy, and i would try them—that is, unless they happened to be drugs. i was getting more and more shy of drugs. i had some blessed instinct which saved me from stimulants and narcotics. i had never used tea, coffee, alcohol or tobacco, and in my worst periods of suffering i never took to putting myself to sleep with chloral, or to stopping my headaches with phenacetin.

at the end of six or eight years of purgatory, i came upon a prospectus of the battle creek sanitarium. this seemed to me exactly what i wanted; this was constructive, it dealt with the body as a whole. so i spent a couple of months at the "san," and paid them something like a thousand dollars to tell me all they could about myself.

the first thing they told me was that meat-eating was killing me. it was perfectly obvious, was it not, that meat is a horrible feeding place for germs, that rotten meat is dreadfully offensive, and likewise digested meat—consider the excreta of cats, for example! i listened solemnly while doctor kellogg read off the numbers of billions of bacteria per gram in the contents of the colon of a carnivorous person. it certainly seemed proper that the author of "the jungle" should be a vegetarian, so i became one, and did my best to persuade myself that i enjoyed the taste of the patent meat-substitutes which are served in hundred calory portions in the big sanitarium dining-room.

there also i met horace fletcher, and learned to chew every particle of food thirty-two times, and often more. i exercised in the sanitarium gymnasium, and watched the sterilized dancing—the men with the men and the women with the women. i was patiently polite with the seventh day adventist religion, and laid in a supply of postage stamps on friday evening. finally, and most important of all, i went once a day to the "treatment rooms," and had my abdomen doctored alternately with hot cloths and ice. by this means i kept up a flow of blood in the intestinal tract, and stimulated these organs to activity; so my constipation was relieved, and my headaches were less severe—so long as i stayed at the sanitarium, and was boiled and frozen once every day. but when i left the sanitarium, and abandoned the treatments, the troubles began to return. meantime, however, i had written a book in praise of vegetarianism—a book which has got into the libraries, and cannot be got out again!

i went on to a new variety of health crank, the real "nature cure" practitioners. vegetarianism was not enough, they insisted; the evil had begun long before, when man first ruined his food and destroyed its nutritive value by means of fire. there was only one certain road to health, and that was by the raw food route, the monkey and squirrel diet. i had gone out to california for a winter's rest, and decided i would give this plan a thorough trial. for five months i lived by myself, and the only cooked food i ate was shredded wheat biscuit. for the rest i lived on nuts and salads and fresh and dried fruits; and during this period i enjoyed such health as i had never known in my life before. i had literally not a single ailment. i was not merely well, but bubbling over with health. i had a friend who said it cheered him up just to see me walk down the street.

i thought that it was entirely the raw food, and that i had solved the problem forever; but i overlooked the fact that during those five months i had done no hard brain work, no writing. i went back to writing again, and things began to go wrong; my wonderful raw foods took to making trouble in my stomach—and i assure you that until you try, you have no idea the amount of trouble that can be made in your stomach by a load of bananas and soaked prunes which has gone wrong! for a year or two i agonized; i could not give up my wonderful raw food diet, because i had always before me the vision of those months in california, and could not understand why it was not that way again.

but the time came when i would eat a meal of raw food, and for hours afterwards my stomach would feel like a blown-up football. then somebody gave me a book by dr. salisbury on the subject of the meat diet. of all the horrible things in the world, a meat diet sounded to me the worst; i had been a vegetable enthusiast for three years, and thought of eating meat as you would think of cannibalism. but there has never been a time in my life when i would not hear something new, and give it a trial if it sounded well; so i read the books of doctor salisbury, which have long been out of print, and have been curiously neglected by the medical profession. salisbury was a real pioneer, an experimenter. he wrote in the days before the germ theory, and so missed his guess regarding tuberculosis, but he perceived that most of the common diseases are caused by dietetic errors, and he set to work to prove it. he showed that hog cholera and army diarrhea are the same disease, and come from the same cause. he took a squad of men and fed them on army biscuit for two or three weeks, until they were nearly dead, and then he put them on a diet of lean beef and completely cured them in a few days. he did this same thing with one kind of food after another, and in each case he would bring his men as near to death as he dared, and then he would cure them. he showed that meat is the only food which contains all the elements of nutrition, the only food upon which a person can live for an unlimited period. as salisbury said, "beef is first, mutton is second, and the rest nowhere."

it was his idea that tuberculosis of the lungs is caused by spores of fermenting starch clogging the minute blood vessels. he claimed that there is an early stage of tuberculosis, in which the spores are floating in the blood stream; he put large numbers of patients upon a diet of lean beef, ground and cooked, and he cured them of tuberculosis, and if one of them would break the diet and yield to a craving for starch or sugar, salisbury claimed that he could find it out an hour or two later by examining a drop of their blood under the microscope. in his books he described vividly the effects of an excess of starch and sugar in the diet. he called it "making a yeast-pot of your stomach"; and you can imagine how that hit my stomach, full of half digested bananas and prunes!

i tried the salisbury diet, and satisfied myself of this one fact, that lean meat is for brain-workers the most easily assimilated of all foods. salisbury claimed that you could not overeat on meat, but i do not believe there is any food you cannot overeat on, nor do i believe that anyone should try to live on one kind of food. we are by nature omnivorous animals. our digestive tracts are similar to those of hogs and monkeys, which eat all varieties of food they can get. one of the common errors of the nature cure enthusiast is to cite the monkey and the squirrel as fruit and nut-eating animals, when the fact is that monkeys and squirrels eat meat when they can get it, and the ardor with which they go bird-nesting is evidence enough that they crave it. if there is any race of man which is vegetarian, you will find that it is from necessity alone. the beautiful south sea islanders, who are the theme of the raw fooders' ecstasy, spend a lot of their time catching fish, and sometimes they kill a pig, and celebrate the event precisely as christians celebrate the birth of their redeemer.

from this you may be able to guess my conclusions, as the result of much painful blundering and experimenting. so far as diet is concerned, i belong to no school; i have learned something from each one, and what i have learned from a trial of them all is to be shy of extreme statements and of hard and fast rules. to my vegetarian friends who argue that it is morally wrong to take sentient life, i answer that they cannot go for a walk in the country without committing that offense, for they walk on innumerable bugs and worms. we cannot live without asserting our right to subject the lower forms of life to our purposes; we kill innumerable germs when we swallow a glass of grape juice, or for that matter a glass of plain water. i shall be much surprised if the advance of science does not some day prove to us that there are rudimentary forms of consciousness in all vegetable life; so we shall justify the argument of mr. dooley, who said, in reviewing "the jungle," that he could not see how it was any less a crime to cut off a young tomato in its prime, or to murder a whole cradleful of baby peas in the pod!

there is no question that meat-eating is inconvenient, expensive, and dirty. i have no doubt that some day we shall know enough to be able to find for every individual a diet which will keep him at the top of his power, without the maintenance of the slaughter-house. but we do not possess that knowledge at present; at least, i personally do not possess it. i happen to be one of those individuals—there are many of them—with whom milk does not agree; and if you rule out milk and meat, you find yourself compelled to get a great deal of your protein from vegetable sources, such as peas, beans and nuts. all these contain a great deal of starch, and thus there is no way you can arrange your diet to escape an excess of starch. excess of starch, so my experience has convinced me, is the deadliest of all dietetic errors. it is also the commonest of errors, the cause, not merely of the common throat and nose infections, but of constipation, and likewise of diarrhea, of anemia, and thus, through the weakening of the blood stream, of all disorders that spring from this source—decaying teeth and rheumatism, boils, bad complexion, and tuberculosis. starch foods are the cheapest, therefore they form the common diet of the poor, and are responsible for the diseases of undernourishment to which the poor are liable.

on the other hand, of course, there are perfectly definite diseases of overnourishment; high blood pressure, which culminates in apoplexy; kidney troubles, which result from the inability of these organs to eliminate all the waste matter that is delivered to them; fatty degeneration of the heart, or of the liver, or any of the vital organs. you may cause a headache by clogging the blood stream through overeating, or you may cause it by eating small quantities of food, if those foods are unbalanced, and do not contain the mineral elements necessary to the making of normal blood. whatever the trouble with your health, it is my judgment that in two cases out of three you will find it dates back to errors in diet. i do not think i exaggerate in saying that a knowledge of what to eat and how much to eat is two-thirds of the knowledge of how to keep yourself in permanent health.