LECTURE XVII. 



INORGANIC FOODS. 

 II. 



WE have started with milk as a standard for determining the require- 

 ments of the animal organism as regards inorganic material. This is 

 justifiable inasmuch as it is certain that milk contains in proper propor- 

 tions all the inorganic salts which are necessary for the development of 

 the growing individual. Under ordinary conditions there is little fear of 

 an insufficient supply of these elements in the case of adults, except, 

 of course, during periods of pregnancy and of lactation. Our ordinary 

 mixed diet contains a sufficient amount of all the inorganic substances, 

 even when on account of social reasons the nourishment is obtained from 

 material which is not of full value. We shall come back to this point. 



In comparing the composition of milk with that of the other foods, we 

 left one important fact unmentioned; namely, the relatively low iron con- 

 tent. There are, in fact, but few articles of food which contain less iron 

 than milk, as is shown by the following table arranged with increasing iron 

 content: l 



1 G. von Bunge: Z. Biol. 45, 532 (1901). Cf. Hausermann: Z. Physiol. Chem. 23, 

 555 (1897) 



380 



