The consequences of an insufficient dietary, says Hodges, are most frequently exemplified in young people, of both sexes, growing school children, boys fitting for college, débutantes in society, young mothers of families, seamstresses, shop girls, &c.; and, although they also appear at other periods of life, and under other circumstances than those which have been enumerated, it is during the years of adolescence that the utilisation of feeding has its supreme value, and its prophylactic and curative effects, as a therapeutic method, are most easily obtained. Sir Andrew Clark, Grailly Hewett, Clifford Allbutt, and others, who have described the ailments which follow inadequate alimentation, have especially urged the necessity for greater attention to the question of diet in the bringing up of families.
The underfed constitute so considerable a class that a large part of medical practice is devoted to attempts at satisfying their importunate demands for “something which shall make them feel better.” To attack with drugs symptoms which are daily regenerated by starvation is labour in vain, so long as that condition is permitted to exist. But if the famished tissues of those who say they are not sick, and there is nothing the matter with them, only that they “do not feel well,” and “cannot eat,” be permeated with the fat which is so often loathed in food—if veins be filled with a more bounteous supply of blood, and if outdoor air be made attainable without the expenditure of an already slender supply of strength—their bodily functions will take on renewed vigour and be reanimated from better life-giving resources, force will be stored up, energy will be developed, and innumerable discomforts evicted. The futile use of iron, quinine, bitters, elixirs, and other so-called “tonics,” either when self-prescribed or methodically directed by physicians, and the insuccess of medicines, as a rule, to relieve the wearisome complaints daily listened to from persons whose mode of living is an injustice to themselves, do not always serve as a reminder that suitable nutriment, in some form or other, is the only real “tonic,” and that its methodical consumption can alone relieve the protean afflictions of many, if not most, of these querulous supplicants. To say to them in a vague and general way that a nourishing diet should be taken, and that anxiety and overwork are to be avoided, is to give weak advice. The most rigid and literal obedience to fixed and precise rules in regard to the quantity and character of their food and the times of taking it—in fact, the carrying out of a process of “stuffing,” practised at short intervals of time, without regard to appetite and pushed to the stomach’s maximum capacity of digestion—is necessary to extricate them from their deplorable situation.
The theoretical standard of a full ration has been given. The conventional standard, however, is an unsettled one. The statement that a person eats as much as other members of his or her family may mean a great deal or nothing, for there are large and small eaters both by habit as well as by example, and there can be no criterion of the amount proper to be eaten under given circumstances except that which is determined by a physician’s judgment. This amount, as has been said, should not only be specified exactly, but its consumption ensured, and nothing but precise and positive evidence accepted in regard to the fulfilment of the specifications given. (R. M. Holmes.)
Function of Food.—The subject is treated from another point of view by F. W. Moinet, in a lecture on Food and Work, read before the Pharmaceutical Society, who observes that as the food we eat or drink—the latter term applying only to the condition of the article used whether fluid or solid—is the only source from which the elements forming the constituents of the body are derived, it naturally follows that no article of food can satisfy the requirements of life which fails to comply with this condition. But as comparatively few articles of food contain all these elements, or in their proper proportion, it follows that we must combine different articles of food together to make a satisfactory meal, i.e. a meal not only sufficient to satisfy the appetite, but also capable of supplying the different elements required by the tissue to replace what has been spent on work. Hence the reason and necessity of living on a varied diet, which experience taught our ancestors long before the scientific facts on which it is founded were discovered. For with the exception of milk, which is a perfect food, no ordinary article of diet contains all the necessary elements. But this is not only a necessity, but also a great advantage, as our food would be very apt to pall on our palates were it always the same, so nature liberally supplies us with a great variety to choose from, which are nearly equally capable of nourishing the body, and at the same time suiting different tastes, which to some individuals is a matter of importance, either from habit or natural peculiarity, still more valuable to the invalid whose recovery sometimes depends not on medicine, but on diet.
Another reason of this variety in nature is that all animals and vegetables are not found to flourish under the same conditions of climate and soil; hence in different countries the food supply is often obtained from different sources, plants and animals, especially the former.
The function of food may be described as twofold:—1st, to afford material to replace what is spent in labour, physical or mental, muscular or brain; 2nd, to supply fuel which is spent in force.
A considerable proportion of our food, especially the fatty and starchy matters, after being digested and assimilated and stored up in the various tissues, is slowly burnt or oxidised by the oxygen which has been carried from the lungs by the blood; the fat is decomposed into carbonic acid and water, which are given off by the lungs and the kidneys and skin. By this oxidation, or burning, heat and force are generated to keep up the temperature of the body and keep the vital functions going, and to supply physical and mental energy, all the internal and external work of the body being performed by the combustion of the stored-up fat in the tissue. Hence the necessity of a regular and constant supply of food to warm the body, supply mental and physical energy, and repair the waste of the tissues. This brings us naturally to consider next whether this twofold function of food is performed by the same or any article of food. In some cases it is; but as most articles of food do not contain the substance required in suitable proportion to perform both these functions, we require to take more than one article of food to make up what the other lacks, and in this way we get a diet sufficient to fulfil both these functions. It is for this reason that articles of food, or their nutritive principle, have been classified according as they contribute especially to the growth and nutrition of the body, or to the production of heat and force, into two great classes:—(a) Heat-producers; (b) Flesh-formers, or non-nitrogenised and nitrogenised compounds.
| (a) Heat-producing, or Non-nitrogenised. | |||||
| Sugar | } | { | Carbon | ||
| Starch | } | composed of | { | Hydrogen | |
| Gum | } | { | Oxygen | ||
| Oils and Fats | } | ||||
| (b) Flesh-forming, or Nitrogenised. | |||||
| { | Carbon | ||||
| Albumen | } | { | Hydrogen | ||
| Gluten | } | { | Nitrogen | ||
| Fibrin | } | composed of | { | Oxygen | |
| Casein | } | { | Sulphur and | ||
| Legumin | } | { | Phosphorus | ||
Of these compounds those which contain nitrogen are used principally for building up the muscles, while those which contain no nitrogen are burnt up in the body to yield heat and force. The flesh-forming compounds are not obtained solely from animal food, as gluten and legumin are derived from the vegetable kingdom, from cereals and peas and beans respectively; while the heat-producers, with the exception of some oils and fats, are obtained solely from the vegetable kingdom. So that for perfect health our food must contain sufficient of both these two classes of compounds to repair the tissues, and to supply heat and force (the mineral substances being contained in these compounds, also partly supplied by the water we drink). As to the relative proportion in which they should be present in our food, there is no hard and fast line; this would be an impossibility unless we were to weigh and analyse every article we eat. We judge by experience what will satisfy the appetite and enable us to feel up to our work. Besides, it must vary considerably according to circumstances,—1st, the amount of work or exercise; 2nd, the climate. Thus physical or bodily exercise compels us to eat more than when idle, our increased hunger or appetite being nature’s method of indicating to our minds that our bodies require food to replace what has been expended in force and to repair the waste of the tissues. Then the colder the climate more food is required, especially of the heat-giving varieties, as more will be spent in keeping up the warmth of the body. Cold is also more conducive to physical work than warm weather, so that for this reason also more food is required in a cold climate.