On entering on the subject of disorders of digestion in early-life it may be stated at once that diet plays the chief part both in the causation and in the treatment. So generally is this recognized to be the case that not infrequently a physical examination of the child is not made, and definite disease may be overlooked. Although one will usually be correct in regarding the diet as the important factor in digestive disorders, it is well to remember that similar symptoms may be induced by organic disease, and to exclude any such possibility before proceeding to dietetic treatment. Digestive troubles are largely preventible by the use of proper foods, properly administered. Unless the symptoms come on acutely and, from the point of view of the mother, alarmingly, medical advice is seldom sought at the beginning. Hence, it often happens that a digestive disturbance which might have been easily cured at the onset is allowed to progress so far before advice is sought that prolonged and careful treatment is necessary. Certain domestic beliefs tend to develop gastric disorders in early life. One of these is that, if an infant is not gaining flesh or is wasting, more food should be given. Another is that if vomiting occurs, the food cannot be suitable, and another should be tried. The criterion of health in the domestic circle is not always in accordance with medical views, for it is summed up in one word - fat. A fat baby in a neighbourhood is responsible for much trouble amongst the surrounding infants. Mothers look with envy on this fat child, and promptly proceed to stuff their own babies so as to produce a similar result. A mother will sometimes seek advice about her infant on the ground that it is wasting, which simply means that it is not as fat as some baby she has seen in the street or in a picture. The so-called wasting infant will often be found to be in the best of health. It may be stated generally that ignorance of the simple rules of infant feeding and neglect of them are the chief causes of gastric troubles.
In the treatment of the various symptoms of indigestion, namely, vomiting, flatulence, colic, diarrhoea, and constipation, one will naturally attend first of all to the diet. The food at first should be such as to give rest temporarily to the disturbed digestive system, which is done by regulating the quantity and quality. Later, a normal diet is to be gradually led up to, as the disordered functions are restored. It is as well in the treatment to ignore any statements as to what the child can and cannot take. No one will deny that there is such a thing as idiosyncrasy as regards food in infancy, but cases of this nature are far fewer than is commonly believed, and certainly far fewer than stated by nurses. The stomachs of most infants and children are quite capable of dealing with ordinary food, and the common forms of indigestion are not due to hereditary tendencies or to acquired diseases, but to improper feeding.
In the following pages it will not be necessary to split up the digestive disorders into a large variety of ailments. We shall consider the more common disturbances and the temporary dietetic measures which are called for before a full physiological diet can be used. Special foods may be ordered for special disorders, and it is necessary to limit their use to the period of disease. Many diets will be referred to which, while beneficial in illness, cannot be employed permanently without serious injury to the child. The physiological diets for infants and children in health have been given in a previous section and will not be treated of again in this connexion.