The effect of nicotine on the growth is very measurable, and the following figures are presented as a fairly satisfactory demonstration of the extent of the interference with growth that may be expected in boys from sixteen to twenty-five years of age, when they are believed to have reached full maturity. For purposes of comparison the men composing a class in Yale have been divided into three groups. The first is made up of those who do not use tobacco in any form; the second consists of those who have used tobacco regularly for at least a year of the college course; the third group includes the irregular users. A compilation of the anthropometric data on this basis shows that during the period of undergraduate life, which is essentially three and a half years, the first group grows in weight 10.4 per cent, more than the second, and 6.6 per than the second, and 11 per cent, more than the third; in girth of chest the first group grows 26.7 per cent, more than the second, and 22 per cent, more than the third; in capacity of lungs the first group gains 77 per cent, more than the second, and 49.5 per cent, more than the third.
These figures have been widely quoted, and generally considered as affording positive proof that college students who do not use tobacco make far greater progress in physical development than is the case with smokers. Without actual figures of increment in measurements, these percentages signify little or nothing. For instance, the difference of 24 per cent, in stature increment reported might mean that the smokers increased 17 millimeters and the non-smokers 21 millimeters, but no one would attach any significance to a difference of 4 millimeters in stature measurement.
A recent study by E. L. Clarke, published in the Clark College Record for July, 1909, shows that 46.3 per cent, of 201 students smoke. The smokers exceed the non-smokers a little in strength and lung-capacity, and 26 per cent, of the smokers won athletic insignia against 16 per cent, of the non-smokers. But in the matter of scholarship, 68.5 per cent, of the non-smokers won honors as against only 18.3 per cent, of the smokers. Mr. Clarke concludes:
1. As a rule the non-smoker is mentally superior to both the occasional and the habitual smoker.
2. As a rule the non-smoker is equal, and probably slightly superior, physically, to all members of the smoking classes except the athletes. It may well be queried as to whether the smoking athlete does not make his gain at too high a mental cost to make it pay. No one would contend for a moment that smoking is the sole cause of these differences. There are numerous other factors that are inseparably linked with it.
The question may be approached from the physiologic, the moral or the economic view-point. In this article, the chief aim will be to determine if smoking exerts any influence upon the physical and mental characteristics of college students; the moral question involved will be considered only incidentally; no attempt will be made to present the economic view-point. The writer, with the cooperation of his assistant, Mr. Hyman Cohen, A.M., made a detailed study of 223 college students from two classes, including all for whom records could be obtained.
