GROWTH. 51 



cover the energy output due to play and activity, the child will auto- 

 matically restrict his activity so that the limited amount of food fur- 

 nished will provide first for growth, primarily stature. 



The relationship between food and height. Too much emphasis must 

 not be laid on the caloric value of food only. It is becoming increas- 

 ingly evident that certain unidentified factors in the food, the so-called 

 "food accessories" or popularly termed "vitarnines," play a very 

 important role in skeletal growth and the subsequent addition of tissue. 

 Practically all of our knowledge of the relationship between food and 

 height, or skeletal growth, has been obtained from observations made 

 by the American investigators, Osborne and Mendel, 1 and McCollum, 2 

 on white rats. These important studies have shown that the presence 

 in the diet of the as yet unidentified " food-accessory substances," 

 popularly termed vitamines, is necessary to normal skeletal growth. 

 If these "food accessories" are absent, there is a stuntage of growth 

 in general, but development is not particularly abnormal. Osborne 

 and Mendel were able, by the removal of these "food-accessory sub- 

 stances" from the diet, to defer the growth of white rats for a prolonged 

 period. Subsequently, by supplying the proper foods and "food 

 accessories," they caused these same white rats to attain normal 

 growth without apparent impairment in condition, thus proving that 

 the growth impulse or capacity for growth may be suppressed for a 

 time and exercised later at a period far beyond the age at which 

 growth usually ceases. Jackson and Stewart 3 found that although 

 different organs in the body did not maintain their normal relative 

 weight during inanition, after the proper food was given they resumed 

 their natural growth and attained adequate size despite the early 

 stunting. Retarded growth, therefore, does not necessarily mean that 

 there can be no hope of attaining perfect adult form and function; 

 on the contrary, when organic disease is absent, there is every reason 

 to believe that there will be proper restitution on a correct diet. 



Food deficiencies may be of two distinct kinds. First, there may 

 be an absence of the "food-accessory substances" which promote 

 growth; second, there may be a caloric deficiency which manifests 

 itself chiefly in the loss of previously stored body material or in a 

 decrease in body storage or growth in weight during the growing period. 

 With a diet insufficient in caloric content, but in which the "food- 

 accessory substances" are still present, skeletal growth continues and, 

 as Waters 4 has shown, even if the diet be very much reduced and much 

 below that required for maintenance, there will still be a long-continued 

 skeletal growth without corresponding gain in weight. Hence it 

 seems as if in the long run, unless children are greatly undernourished 



1 Osborne and Mendel, Carnegie Inst. Wash. Pub. No. 156, 1911. 



2 McCollum, The newer knowledge of nutrition, New York, 1918. 



3 Jackson and Stewart, Am. Journ. Diseases Children, 1919, 17, p. 329. 



4 Waters, Proc. Soc. Promotion Agr. Sci., 1908, 29, p. 3. 



