IV. Fattening Foods

From what has been said it is quite clear that all articles of food that incorporate caloric values that become available for the organism may also be considered articles that can be used for fattening purposes. The availability of the caloric content for the organism is, of course, a fundamental condition and it is only this property that characterizes any article that is eaten as a food. Carbon and hydrogen, for instance, have an enormous caloric value. They are incombustible, however, in the organism, and hence constitute no source of energy for the latter and are not foods. Another condition that the introduced material should fulfill is that it must be non-toxic and in no wise injurious to health. This point must always be considered in judging the value of alcohol as a food (see below).

Fundamentally it is immaterial which one of the main articles of food is employed for fattening, immaterial whether we use proteids, fats or carbohydrates. Here the practical rather than the theoretical point of view must be considered, and such practical considerations may lead us in different cases to employ different articles of food; for instance, one would never attempt to increase the weight of a diabetic with carbohydrates, of a gouty individual with meat, of an icteric individual with fat. In each case an individual study of the metabolism and of the capacity of the digestive apparatus must be carefully made; otherwise failure is assured from the beginning.

Aside from these peculiarities the different articles of food can be employed vicariously, according to the well-known law of isodynamics, in so far as their fattening value is concerned. That is, such quantities of the different articles are equivalent that introduce into the organism an equal quantity of available energy.

As long, however, as one is confronted with the task of accomplishing the greatest possible good with the least possible inconvenience to the patient, certain practical standpoints enter into the equation, and it will then be found in practice that the different articles of food are by no means equivalent. It is necessary, therefore, to briefly discuss the different articles of food.