In regard to the diet best adapted to different constitutions in mature age, I have already confessed that I have little new information to offer. In determining the question, several other circumstances besides the mere temperament require to be considered. A more or less laborious mode of life, for example, will require a more or less nutritious diet, whatever the original habit of body may be. In like manner, if any temperament be in excess, and we wish to repress its predominance, the same kind of food which is suitable for it in a lower degree will no longer be applicable. Thus, when the lymphatic constitution is predominant, and our object is to diminish its ascendency, and stimulate the system to greater vigour, a larger proportion of solid nourishing food, combined with increased exercise, will be more proper than if there is no such excess. Where, on the other hand, the nervous or sanguine temperament preponderates, a plainer and less exciting regimen will be necessary than where the constitutional tendencies are more equally balanced.
The power we possess of modifying the constitution by well-directed regimen is very great, and only requires to be sufficiently investigated to have due importance assigned to it in conducting physical education. This is well exemplified in the art of training, where diet and exercise are reduced to a practical science for the attainment of certain results, and with remarkable success. In the hands of a trainer, the breathless and oppressed frame of a person over-burdened with lymph and fat speedily becomes converted into an active, firm, and well-conditioned organization, exhibiting a promptitude of action of both mind and body the very opposite of its former manifestations; and if such a change can be effected by rigid adherence to rules, in the course of two or three months, we may easily conceive the degree of improvement which would follow the uniform observance of proper regimen and dietetic precepts in ordinary society. In improving the moral and intellectual as well as physical condition of the working-classes, the influence of food, air, and exercise, will soon be discovered to possess a degree of importance of which at present scarcely a suspicion is entertained. They constitute, in fact, the very foundation of a systematic education; and mere intellectual cultivation will fail to produce its full beneficial results, till the organization by which the mind operates be itself improved by a treatment in harmony with its own constitution.
If it be impossible for me to communicate sufficient information to enable each of my readers at once to determine beforehand the kind of diet which is likely to suit him best, it will give him at least some satisfaction to know, that, by observing personally what kind of food agrees best with his stomach and constitution, he may soon obtain the necessary information for himself. When we refrain from eating too much and at unreasonable hours, and are not conscious of any undue oppression or discomfort after our meals, but, on the contrary, feel light or refreshed, and, after a time, ready for renewed exertion, we may rest assured that the food which we have taken is wholesome and suitable for us, whatever be its nature and general effects. Whereas if, without committing any excess or other dietetic error, we experience the opposite sensations of oppression, languor, and uneasiness, we may be just as certain that our food, whatever its general character for lightness and digestibility, is not wholesome or suitable for us under our present circumstances. So that, with a little care and trouble, we shall rarely be at any loss to find out what we ought to eat and what to avoid; and, accordingly, it is notorious that indigestion from a wrong choice of food is induced at least nine times by wilful indulgence, for once that it occurs from errors originating in ignorance alone. If the proper quantity of food be not exceeded, and the other conditions of digestion be carefully fulfilled, the risk of mischief from an erroneous choice of aliment will be greatly diminished.
After the full exposition of the laws of digestion given in the first part of this work, I need hardly add, that although there are very few articles of diet which a person in health, and leading a sufficiently active life, may not eat with impunity, there are, nevertheless, some which ought to be preferred, and others which ought to be avoided, by those whose digestion is impaired. Thus, vegetables are, generally speaking, slower of digestion than animal and farinaceous aliments, and consequently, when digestion is feeble, are liable to remain in the bowels till acetous fermentation takes place, and gives rise to acidity and flatulence. Fat and oily meats are nearly in the same predicament, and hence both form unsuitable articles of diet for dyspeptics. Soups and liquid food are also objectionable, both because they are ill adapted for being properly acted upon by the gastric juice and by the muscular fibres of the stomach, and because they afford insufficient nourishment. From the former cause they frequently impair the digestive functions; and from the latter, they induce diseases of debility which it is difficult to subdue. Daily experience furnishes examples of stomachic disorder from eating soups, especially as preliminary to an otherwise substantial dinner; and the fatal epidemic which prevailed a few years ago in the Milbank Penitentiary, was distinctly ascertained to have been partly caused by an insufficient and too liquid diet. It is common, indeed, to see heartburn and indigestion of recent origin cured simply by giving up soups and vegetables, and diminishing the quantity of liquid taken at breakfast and tea.
When, from the state of health or other causes, chicken-tea, beef-tea, veal-broth, or other kinds of soup, require to be given, their digestibility will generally be promoted by the addition of bread or rice to give them consistency, and by taking little or no other food along with them. Even vegetables, when taken alone, are sometimes digested without difficulty, where, if mixed with other substances, they disorder the stomach. Dr Abercrombie mentions a very remarkable instance of this kind in a gentleman who “had been for many years a martyr to stomach complaints, seldom a day passing in which he did not suffer greatly from pain in his stomach, with flatulency, acidity, and the usual train of dyspeptic symptoms; and, in particular, he could not taste a bit of vegetable without suffering from it severely. He had gone on in this manner for years, when he was seized with complaints in his head, threatening apoplexy, which, after being relieved by the usual means, shewed such a constant tendency to recur, that it has been necessary ever since to restrict him to a diet almost entirely of vegetables, and in very moderate quantity. Under this regimen, so different from his former mode of living, he has continued free from any recurrence of the complaints in his head, and has never been known to complain of his stomach.”[52] In this case, however, both the very moderate quantity of vegetable food to which the patient restricted himself, and possibly also the gradual adaptation of the gastric juice to the nature of the food, had no small share in the subsequent improvement of his digestion.
Dr Beaumont mentions, as a general result from his experiments on St Martin, that vegetable food is slow of digestion; but it is much to be regretted that he gives the particulars of only one or two trials, which lead to no very important results. In one of these already mentioned, St Martin ate “nine ounces of raw, ripe, sour apples, at 2 o’clock 35 minutes. At 3 o’clock 30 minutes, the stomach was full of fluid and pulp of apples, quite acrid, and irritating the edges of the aperture, as is always the case when he eats acescent fruits or vegetables.”[53] In another instance, ten ounces of raw cabbage were given, and in two hours not a particle of it was to be found in the stomach; while on a third occasion, half a pound of raw cabbage, cut fine, and macerated in vinegar, disappeared in little more than one hour and a half! If in the latter experiments the cabbage was really digested, and not merely propelled out of the stomach into the intestine, we shall be forced to admit that we have still much to learn concerning the digestibility of different kinds of food, for the result is contrary to all generally received opinions. When vegetables are allowed, great stress is commonly laid upon the necessity of their being thoroughly cooked; and yet, according to these experiments, raw cabbage is very nearly as digestible as soft boiled rice or sago! It is strange that Dr Beaumont should not have remarked this anomaly, which he seems not to have done, since he neither attempts to explain it nor alludes to it as any thing extraordinary. My own suspicion is, that the cabbage was not entirely digested, but had merely passed through the pylorus into the intestine.
Dr Beaumont’s testimony in favour of farinaceous vegetables is, however, more precise and satisfactory. In some of his experiments, St Martin digested completely a full meal of boiled rice, seasoned with salt, in a single hour. Soft custard and boiled rich sago, sweetened with sugar, and taken in quantities of a pint each time, were disposed of with nearly equal dispatch, and “there was no acrimony of the gastric contents, or smarting of the edges of the aperture, during their chymification, as is usual in most vegetable and farinaceous aliments;” on the contrary, the sago “seemed peculiarly grateful to the surface of the stomach, rendering the membrane soft, uniform, and healthy.”[54] In these instances, it ought to be remarked, nothing else was eaten at the same time; so that the stomach was not oppressed by quantity.
In early life, when digestion is vigorous, the system excitable, and the habits peculiarly active, a full proportion of vegetable and farinaceous food is proper and salutary. Morning and evening meals of this description, prepared with milk, or taken along with it, are very useful—animal food being reserved for dinner alone. But as age advances and excitability diminishes, and perhaps also as habits of activity and exposure to the open air are changed, the same proportion of vegetable and farinaceous food can no longer be digested so easily, and therefore ought not to be continued.
Pastry, rich cakes, puddings, and other articles containing much fatty or oily matter in their composition, are perhaps the most generally indigestible of all kinds of food, and consequently ought never to be eaten when the tone of the stomach is impaired. There are states, however, in which oily articles seem to agree better than lean. I have seen very fat fried bacon, for example, digested with ease at breakfast, where even a small potato would have disordered the stomach. It is very difficult to afford any explanation of the fact, which, however, is not uncommon. Perhaps it is dependent on a peculiar state of the biliary secretion, for Dr Beaumont often remarked that the presence of bile in the stomach facilitates the digestion of fat and oily aliments, and that, even out of the stomach, gastric juice dissolves suet faster when a little bile is added to the mixture, than when the juice is pure. He mentions, moreover, that he never found bile in the stomach, at least during health, except when food of an oily kind had been eaten; and, in accordance with this, I have generally noticed that fried bacon agrees best with what are called “bilious” subjects. Still, however, the quantity must be small, otherwise it will prove injurious.