But this, too, was found to be an error, in so far as it was only a part of the truth, for it was next ascertained that even provision for a suitable balance of the five food groups was not enough to nourish us, but that we must consider the heat and energy producing properties of these component parts, as measured by the caloric unit, and each must daily take in the requisite number of calories if we would keep our engines going.
It is now known that even this is not enough, for we may eat food in ample quantities, consisting of the properly balanced fats, proteids, carbohydrates, minerals and water, and it may daily yield the required number of calories, and still we may suffer from seriously faulty nutrition.
Hess and Unger state in this connection, that, “in framing dietaries for children and adults, our minds are still focused on insuring a sufficient supply of calories in the food, and we have not yet reacted in practice to the newer knowledge that ample carbohydrates, fats and proteins may constitute a dangerously deficient diet.”[[10]]
We find an explanation for this fact in the comparatively recent recognition of three substances, as yet not clearly understood, which are contained in a certain few articles of food, each one of which is essential to growth and normal health and well-being, though not necessarily concerned in the production of heat or energy. Various terms have been applied to these mysterious, but necessary substances, such as vitamines, accessory food substances as applied to all, or fat-soluble A, water-soluble B and water-soluble C to designate them separately.
A surprisingly small amount of each of these substances is sufficient to meet the needs of an individual, but no one of these, even in this small amount, can be safely dispensed with, for if the diet is deficient, or lacking in one or more of them some form of nutritional disturbance will result. It may be severe enough to be diagnosed as a disease, or it may be only enough to keep the individual below a normal state of health.
When the disturbance is profound enough to produce a definite, recognizable condition, it is designated as a deficiency disease, of which there are three: scurvy, beri-beri and xerophthalmia. With these are sometimes included rickets and pellagra. The exact cause of the two latter disorders is not definitely known but both are associated with faulty nutrition. Poor hygienic conditions may enter into the causation of rickets, and infection may be a factor in the occurrence of pellagra, but neither disease appears among those who are suitably fed while both diseases may be produced by faulty diet and both may be cured with suitable food.
But probably of graver importance to the public welfare than the well defined nutritional disturbances, themselves, is the fact that between a state of good health and the level upon which a disease is recognizable is a long scale, along which are ranged an uncounted army of under-par, half-sick people. These are the ones who are tired, nervous, susceptible to infections, with feeble recuperative powers, and in general are more or less ineffective in the business of life.
It is this borderline state, or as Dr. Goldberger terms it, “the twilight zone,” which cannot quite be called disease but is not health, that is serious to the masses, for diagnosed disease is given treatment, but nervousness, lack of energy and endurance, weakness and inefficiency are not treated; they are merely tolerated, as a rule. The sufferers fail to reach their highest possible development and they fail to be of highest value to society.
This is the condition which can be so largely prevented by giving the baby a good nutritional foundation; this must be started during its prenatal life, carried through the nursing period and then continued throughout the rest of his life. Since the nurse is very likely to be entrusted with the arrangement of the patient’s dietary, being told merely to give a liquid, soft or light diet and possibly to avoid certain articles, it will mean much to the coming generation if nurses at large are able so to compose the various diets for the expectant and nursing mother, that they will provide not only the requisite fats, proteids, carbohydrates, minerals and water and yield the necessary calories, but also contain all three protective substances: fat-soluble A, water-soluble B and water-soluble C. It can be demonstrated that when these food factors are not present in the mother’s diet, they will not appear in her milk, and accordingly will not be supplied to her baby.
This is the crux of the whole matter. If the mother’s diet is faulty, her milk will be faulty in the same respect and the baby will start life with tissues which contain an inadequate amount of the substances that are necessary to make them sound and promote health.