408 ISIDOK GKEENWALD 



is high enough. From Sherman's compilation (page 401) it is evident 

 that this is 75 per cent or more above the minimum requirement. The 

 danger of falling below the minimum protein requirement is, therefore, 

 slight. As Bayliss said, "Take care of the calories and the protein will 

 take care of itself." That is certainly true of the minimum for mainte- 

 nance but it is not quite so evident that the optimum will be thus attained. 



Liberal Protein Intake a Possible ' ' Factor of Safety" (Meltzer) . In a 

 memorable lecture delivered in 1906, Meltzer called attention to "The 

 Factors of Safety in Animal Structure and Animal Economy" and sug- 

 gested that the tendency of mankind to seek a level of protein metabolism 

 above the minimum might be such a factor of safety. Just as we are pro- 

 vided with kidney, liver and lung tissue in excess of the apparent minimum 

 requirement, so, too, the excess of protein above the minimum determined 

 by experiment might serve as a factor of safety to cover emergencies and 

 insufficiencies some of which we may not at present be able to recognize. 



Aside from its value as a factor of safety, there are not wanting evi- 

 dences of the desirability of a rather liberal supply of protein. Not only 

 do the more vigorous and prosperous individuals consume a liberal al- 

 lowance of protein but so also, do the more vigorous nations. This may be 

 effect rather than cause and, undoubtedly, is so in many cases with in- 

 dividuals. Meat and other protein foods are prized for a number of reasons 

 including their agreeable taste, stimulating action, etc. This has led to 

 a comparison of the desire for a liberal allowance of protein with the 

 desire for alcohol. This seems to be based upon entirely too superficial 

 resemblances. We now have a fairly good conception of how and why al- 

 coholic beverages came to be so regularly employed by man. We know 

 fairly well how they act to secure the effect desired. We know what are 

 the consequences of excessive indulgence and even of the regular use of 

 small quantities. We also know that not only scattered individuals for a few 

 months or years but entire peoples for generations have maintained them- 

 selves in full health and vigor without the use of alcohol. There is to- 

 day no such body of evidence in respect to the advantages of a low-protein 

 diet. Some protein is needed. A slight, or even moderately great excess 

 can scarcely be so very disadvantageous. When overindulgence in protein 

 shall have been shown to be followed by ill effects at all comparable to 

 those following the excessive use of alcohol, comparison will be in order 

 but hardly until then. 



Change of diet of whatever character has too often led to improvement 

 in clinical condition for one to lay much stress upon the fact that Demuth 

 observed such improvement on increasing the protein content of the diet of 

 some of his patients. But such results as those reported by Moulinier with 

 some 72 Indo-Chinese taken from Annam to the Yangtse valley as laborers 

 are not so readily dismissed. The men first fed themselves as they had been 



