We hear much of clinics for the removal of diseased tonsils and adenoids, and for the repair of defective teeth, but almost nothing of a fundamental nature about the adoption of habits of living which would in great measure exempt the next generation from these physical burdens. Partial physiological exhaustion as exemplified in chronic constipation, hypersensitive-ness of the nervous system, diabetes and kidney lesions has become so common that they attract little attention except from the patient and his physician, yet there is much reason for belief that a more rational system of living, prominent in which would be a wise choice of foods, would in great measure cause the disappearance of these debilitating conditions.

The trouble seems to be that we are still retaining habits of thought which must sooner or later become antiquated. Case reports, autopsies and histological studies still focus our attention upon the nature of the lesion, its accurate description, and its differentiation from other conditions. Bacteriological studies and the triumphs of the serologist in immunization against infectious disease, hold most of our attention, while the physiology of normal conditions, receives but little consideration. Without minimizing the importance of pathology, bacteriology and parasitology in contributing to human health and comfort, it may well be asserted that the time has arrived when greater attention should be given to the most fundamental problem of all, viz.: the supervision of the conditions under which the normal development of the individual takes place. An effort must be made to perfect the environment so as to make the many structures of the body function in a manner which approximates the physiological ideal. Such an attitude toward health matters would necessitate the recognition as of paramount importance for the realization of its aims, the optimal regulation of the chemical medium by which the tissues grow and are sustained. Technical studies have brought to light what casual inspection failed to discern, that our most effective defensive barriers against most of the dangers to which our environment exposes us lie within us. Perfection of physiological development, and the preservation unimpaired of the functions of the organs and tissues of the body assure, in great measure, immunity against the painful effects of certain diseased conditions. Among all the hygienic factors which influence the welfare of human beings or the lower animals, the nutritional factor stands first in importance. It is hoped that the illustrations presented of the manner in which the diet may be selected so as to form a great bulwark in the protection of vitality are sufficiently convincing to lead to a better appreciation of this much neglected agency for the promotion of health.

Fig. 19. - Illustrates the marked difference in the quality of the skeleton of rats which were fed on diets which were poor and good respectively. The bones at the top (Lot 2883) are those of an animal whose diet was satisfactory except that it was too poor in calcium. Note the dark coloration due to hemorrhage; the detachment of the head from the femur; the separation of the bones of the skull; the deformity of the pelvic bones; the crooked form of the radius and ulna; the inferior development of the scapula and the failure of the bone of the mandible to grow out around the base of the incisors as far as it should. Note also that these incisors are growing at a wrong angle and are too long and poorly formed.

Rat 2884 took the same diet as the above but with calcium carbonate added. Its bones were much lighter in color, and were dense and well formed.