Normal height

In the first place, what is the normal height of the child? With adults there is no such thing as normal height. The ranges of height with men and with women are very extended indeed. We form definite opinions as to whether a man is especially short or especially tall, but no one would care to state the normal height for man. The average height for a man is commonly given as 170 cm., but it is granted that there are very wide variations from this average height. With adults, then, the difference between normal and average is clearly recognized, but the average is taken as normal. Thus, the heights of a large group of individuals representing the general run of the population are measured and averaged, and this average value is considered as the normal value. We contend that this procedure is entirely erroneous when applied to children, although it is regularly employed and is a basis of most of the tables and charts in current use. With children there should be, or at least there is properly supposed to be, a reasonably definite height for an age. It has been stated earlier in our discussion that age, weight, and height are rather closely correlated with children, in contradistinction to the situation with adults. As children grow older they increase in height and weight approximately in the same degree. It has been repeatedly shown that racial characteristics appear very prominently in height. Our American population is by no means of a pure strain, and a group of children from a large public school, especially in our big cities, may represent a large percentage of foreign blood. Under these conditions an average figure may certainly be obtained, but we believe it is not justifiable to consider this average figure as normal. From the consideration of the charts in which our private-school data were plotted (figs. 4 and 6), it is clear that the private-school children on the whole are considerably taller for their age than are our laboratory children, or, indeed, the extensive series we quote from other writers. In other words, it seems evident that the conditions obtaining with the children of private schools in eastern Massachusetts produce a greater skeletal growth, as indicated by the height. On this basis, all of these private-school children are supernormal; in other words, they are certainly above the average, and the question immediately arises, "Is the average to be considered as normal?"

If one objects to the values found with the private-school children as normal values, no exception can be taken to the expression "ideal value." Hence one should compare the height and weight of a child not with the average or the fictitious normal, but with the ideal, which is unquestionably represented more nearly by our data from private schools. We wish here especially to emphasize the difference between average, normal, and ideal. When a child is short for his age this instantly indicates one of two things. In the first place, the child may be the offspring of a race of people or of parents of normally short stature; secondly, there may be a serious deficiency in the growth-producing factors in the diet. This deficiency in growthproducing factors is to be sharply distinguished from the caloric content of the diet, for it has been shown, with animals at least, that when they are maintained upon a diet of constant caloric value during the active period of growth, skeletal growth is made at the expense of the addition of tissue.

We should no longer, then, compare the height of our children to the average and call this normal. The fact that a group of 800 privateschool children may attain a height for age considerably above that of the average or so-called "normal" can be taken only as an index of the fact that this average represents children living under conditions which do not produce the best growth. In any educational campaign for the promotion of child welfare it is important to lay special stress upon those conditions favoring the largest skeletal growth. Consequently we believe that all previous charts indicating height for age are not ideal and represent simply a group of the population that has been stunted, in part at least, by abnormal living conditions and perhaps deficient dietary constituents. In laying down this thesis we are, of course, open to the criticisms that our private-school children were less contaminated by racial commingling and that the shorter statured people did not send their children to these private schools -- in other words, that our private-school children represent the more purely typical American or Anglo-Saxon type. To a certain extent this is probably true, but we are not in a position to throw definite light upon this subject. We think it highly improbable, however, that this explanation completely accounts for the greater height of this group of children. For an estimate of the ideal height of children we believe, therefore, that one should rely not upon the so-called "normal" curve, but more nearly upon an ideal curve which is measurably higher than a normal or average commonly given. On this basis many analyses of the measurements of children which indicate that the children are above normal height simply mean that the normal level is arbitrarily adjusted at too low a point. Nutrition experts and pediatricians must hold this important relationship clearly in mind and not be content with the statement that a child is of average height when the possibilities of greater skeletal growth are presented by better living conditions, medical treatment, and general care.