BIOLOGY IN HUMAN AFFAIRS 



the use of sanitary latrines; second, avoid infection of the 

 person by wearing shoes and otherwise eliminating contact 

 with the soil. Moreover, several very efficient drugs were 

 found to rid the sufferer of worms already at home within 

 him. But scientific, governmental care and insistence are 

 scarcely sufficient to work the needed reforms in dyed-in- 

 the-wool hookworm localities, such is the sloth and 

 ignorance and poverty of the population; and only long 

 continued efforts can apply successfully the benefits that 

 science affords. 



In recent years zoological research has made rapid 

 advances in the department of physiology, particularly in 

 regard to nutrition and the endocrine system. Some of the 

 early results of this work proved to be of immediate 

 practical value and inspired sensational treatment in the 

 newspapers and in books of ephemeral popularity. We can 

 easily recall various food faddists, the vitamine advertisers. 

 Dr. Steinach's fountain of youth, "Black Oxen," the 

 monkey glands, and other such headliners of yesterday; 

 but the follies of modern publicity need not blind us to the 

 underlying scientific realities. 



The first necessity of human health is food; and it is 

 in the precise constitution of food materials that modern 

 nutrition studies have made remarkable discoveries of 

 great theoretical and practical value. It has been shown 

 that ordinary foodstuffs, to be sufficient for bodily welfare, 

 must contain certain substances, very powerful in effect 

 but very small in quantity, in addition to the proteins, 

 carbohydrates, and fats which make up more than 99 per 

 cent of their bulk. These substances are the vitamines, and 

 no amount of food material, however good it may appear, 

 will keep a mouse or a human being in normal condition, 

 if it lacks any of these peculiar elements. 



The vitamines are mysterious. Their exact nature and 

 chemical constitution are by no means understood, but 



[298] 



