It is important not only to eat those foods that are best adapted to the human constitution and to eat them properly prepared, but also to eat them in ways that assure the best results in digestion. A food that may be easily digested by a person in vigorous health and full digestive power may be indigestible to a weak and sick individual. Foods that are not well chewed, foods taken in too great quantity, foods that are spoiled, even if camouflaged with seasonings, prove harmful.

Perfect obedience to the laws of being is the only means of ensuring perfect health and an adult, with fully developed brain and whose reasoning power is mature, is inexcusable if he (or she) does not render intelligent and implicit obedience to these immutable laws.

Because of the importance he attached to food and correct diet, Trall said editorially in December 1858 that he was accused of being a mono-maniac on the subject of eating. In spite of this he declared that "in all our prescriptions for invalids, let what will ail them, we attend to the dietary as well as the bathing, the breathing, the exercise, etc." One patient complained that in all of Trall's advice to his consultants he "insisted on a correct dietary in every case." This consultant was "willing to admit that some folks ought to attend to diet, but that all should seemed to him to be making one remedy apply to all kinds of persons and all manner of diseases." It seems that he overlooked the fact that dietary indiscretions were general.

The prevailing customs of our society provide a very poor guide, not only to the times of eating, but as to the quantity and kinds of things to be eaten. We eat for mere gratification, far too much; for principle, far too little. As a necessary consequence of such eating practices, we curtail our gustatory enjoyment and reduce our physical and mental efficiency. The man who cannot enjoy a plain, simple meal of a few foods, these simply prepared or in their natural state, is not yet converted to the Hygienic diet.

The unprocessed, uncontaminated, unadulterated natural article of food which we like best is best for us and the natural, unchanged article for which we have a dislike is not good for us. This is true as a principle applicable to the race as a whole and cannot be confined to the individual likes and dislikes. What we have here said of foods applies equally as certainly to medication. Nature never provided man with an appetite for any or several of her compounds that will injure him, nor withheld an appetite for one that will do him real good. When nature takes away the appetite for a wholesome substance, it is because we have eaten enough of it. When she is ready for us to eat again, she provides such a desire for food that we relish food and nothing else will do.

Nature provides us with whole foods and we alter them until they are no longer adapted to the nutritive requirements of our constitution. Our nutritive adaptations, represented by the sense of taste, are no longer sure guides to eating after our foods are so much altered. For this reason man's normal instincts fail him when he attempts to live upon a diet of processed and refined foods that have been sweetened and seasoned in a way to deceive his sense of taste.

It will not do to advise: "Be careful of your diet." Such advice is empty of precise meaning and each person will interpret it to suit his own opinions and whims. One will think that he is "being careful" if he omits the third cup of coffee; a second will think the advice is carried out if he eats only one large slice of roast pork; a third will be content to merely reduce the condiments and trimmings he customarily eats. It is essential that the diet be specified and, if need be, that we see that the patient is careful in abstaining from everything but water. The body casts off nothing but useless matter and excess, but such are the prevailing eating practices that our excretory organs must work overtime to free us of excess food and of the many foodless harmfuls that we imagine we enjoy.

Our eating is largely a matter of habit and commonly we cultivate our eating habits without intelligent thought. We are inclined to follow the general practices of those around us until our habits dominate our lives. When habit has become master, so that it is found difficult to turn down food, it should be realized that good habits can also become master and that once old habits have been broken and good ones cultivated in their stead, it will be found that the new habits are even more pleasurable. One of our worst eating habits is that of overeating. In this country, at least, overeating is practically universal.

The bestial rivalry and shameless prodigality of the treasure of life which are the concomitants of feasting and revelry, where food and drink are plentiful and tempting, grow from ignorance and wilful disregard of the true physiological relations of food and drink to the body. When visiting friends and dining with them, we are customarily urged to eat more and still more after we have eaten all we desire, perhaps more than we should. Host and hostess continue their urgings and, if we are not strong, we are likely to be influenced by their importunings. This is a social crime for which there seems to be no remedy short of social enlightenment.

What is the difference between the man who kills himself with habitual gluttony and the man who destroys his life with habitual drinking? The early Hygienists strongly recommended the two-meals-a-day plan long before Dr. Dewey crusaded for the no-breakfast plan. It was the view of Trall that "it is of little consequence whether you eat two or three meals (a day), provided you are correct in the whole quantity of the food taken and are correct in your other habits." In discussing the superiority of the two-meal plan, he said: "Whether two meals are eaten or three, one should be moderate in quantity and choice of materials." Moderation in eating may be said to be of paramount importance.

The very existence of teeth implies the need for chewing; the existence of salivary glands and their secretions implies the necessity for insalivation of food; the existence of salivary amylase implies the need for its digestive action. Even the infant masticates, in a physiological sense, the first meal it draws from the maternal fountain. Yet, heretofore physiologists have tended to deprecate the importance of chewing and of salivary digestion.

Just as physiologists have, heretofore, tended to underestimate the importance of mouth digestion, so they tend to underestimate the importance of gastric digestion. It is not unusual to read in scientific works that "so far as the digestive process is concerned, the stomach is a helpful, but not a necessary organ." One standard biological text says that "in addition to storing and softening the food, the stomach serves as a disinfector; for very few bacteria can survive the high degree of acidity of the stomach." Thus the importance of the work done in the stomach in initiating protein digestion is regularly discounted, while the continuation of starch digestion in the stomach is considered unimportant.