This section is from the book "Practical Dietetics With Special Reference To Diet In Disease", by William Gilman Thompson. Also available from Amazon: Practical Dietetics with Special Reference to Diet in Disease.
The proper nutrition of all the tissues of the body is directly dependent upon the quality of the blood plasma and of the amount of oxygen conveyed by the corpuscles. A very slight'departure from the average composition of these elements will sooner or later result in diminishing the nutrition and functional activity of all the organs in the body, notably those of the digestive system.
Anaemia, whether acute and due to haemorrhage or disease, or chronic from any cause, by depleting the cellular elements of the blood, interferes with the proper oxidation of food after absorption. On the other hand, a diet which is insufficient in amount or inappropriate in quality, if long continued, is certain to produce an impoverished condition of the blood with a diminution in the number of corpuscles; hence there is a double relation existing between the power of the blood to insure complete absorption and metabolism, and of the food itself to maintain the normal balance of the ingredients of the blood. Anaemia, therefore, demands special feeding, the basis of which should be an effort to restore as soon as possible the proper number of red corpuscles and the normal quantity of other ingredients of the blood by a diet which is nutritious and abundantly rich in nitrogenous food given in some easily assimilable form. When proteid food is excluded from the diet for some weeks the haemoglobin of the red blood corpuscles is considerably reduced in amount and hydraemia ensues, but the pigment is always increased by an excess of nitrogenous food.
Anaemia and chlorosis are most common at the age of puberty, and immediately thereafter, among young girls who are growing or who are overworked at school or in factories while beginning menstruation, and who are improperly fed. The diversion of considerable nervous energy for other functions than those of the circulation at this time may interfere somewhat with the nervous mechanism of digestion and absorption. In other cases there is a constitutional or hereditary weakness of the digestive system, which is aggravated by an exceptional strain or overwork of the nervous system. The phenomena of growth and development of the different organs necessitates the consumption of a relatively larger quantity of good food than is needed later in life for merely maintaining the equilibrium of the tissues and restoring the balance of material used in the production of energy. Growth implies the building up of new material and a renewal of the old as well. At the period of growth, therefore, there are always unusual demands upon the nervous system, and overstrain at this time is to be especially guarded against.
Among the many symptoms referable to the nervous system which occur in the course of protracted anaemia are languor, vertigo, various forms of neuralgia and megrim, with indefinite muscular pains, which to some extent are produced by enfeebled circulation, which allows waste material produced by muscular action to accumulate in the tissues. Depression of spirits and drowsiness are also observed, and palpitation is easily excited. The poor circulation may result in the production of fainting, or of oedema in the lower extremities. In advanced anaemia it is found that not only is the normal rate of tissue metabolism impaired, but there may be modifications in the relative consumption of certain foods by the tissues. A large excess of urea is commonly observed, which indicates an active combustion of nitrogenous substances. The view is widely held that owing to the small number of the red disks, or oxygen carriers, the final oxidation of fatty matter is retarded, and it is for this reason that anaemic subjects very often appear plump or even corpulent from the deposition of a large amount of fat derived from incomplete combustion of fats and starches, whereas their muscles, from the increased nitrogenous waste, are reduced in size and are weak.
Van Noorden, Kraus, Bohland, and others dissent from this argument and believe that chlorotic patients feel tired, sleep long, and are disinclined to expend energy in muscular exertion, and less energy than usual goes into heat production, and as they sometimes eat abundantly of sugars and starches, they necessarily store up fat.
In many cases of extreme anaemia, found especially among young chlorotic girls, the dietetic treatment must be accompanied by careful regulation of all hygienic conditions. Sufficient rest for the tissues, and especially for the digestive organs, must be secured. These patients, who appear so well nourished, may in reality be quite feeble, and it is a great mistake to compel them to rise early and perform tasks and indulge in exercises of the same character and degree with those of healthy children. For many patients it is well to insist on prolonged and continuous rest in bed. For others it will suffice to restrict the activities of the day by permitting the patient to rise shortly before noon, and to insist upon rest being taken on a lounge both before and after meals in order to secure more perfect digestion. These patients must be cautioned against allowing themselves to become unduly fatigued. They are often able, under the influence of stimulants and excitement of various sorts, to perform feats of exercise or endurance which are equal to those of healthy persons, but a strong reaction is certain to follow, and a steady but slow progress will often be checked for several weeks by infringement of necessary regulations.
In such cases, however, as soon as decided improvement is evident, and in all the milder cases, it is desirable to enforce rules for gentle exercise in the open air, and the patient should be outdoors nearly all the time whenever the weather permits. The exercise should be supervised and slowly increased in stout subjects, so that they gradually consume their superfluous fat. If the climate is unfavourable the cure will be much more rapid if the patient can be moved to a more salubrious locality. Fresh air is more important than exercise, for an abundant oxygen supply increases the appetite and distinctly favours the assimilation of the food.