280 alsberg: biochemical analysis of nutrition 



of importance, since it proves that the substance is not a lipoid. 

 Lipoids are complex fat-like substances containing both nitrogen 

 and phosphorus. It has been claimed that a diet without lipoids 

 will not support life. The absence of nitrogen from the growth- 

 promoting substance of butter indicates that it is not related 

 to the vitamine of rice which is almost certainly a nitrogenous 

 base. The vitamines are substances of unknown composition, 

 found in certain foods and essential to life. In the polishing 

 of rice the vitamine is removed. An individual living upon a 

 diet of polished rice will develop a disease known as beri-beri, 

 frequently found among rice eaters. There is apparently a 

 whole series of substances found in foods which are necessary 

 to life. The absence of certain of them is believed to produce 

 scurvy. A similar hypothesis has been advanced concerning 

 the disease pellagra. 



Little is known as yet concerning the chemical nature of these 

 substances. They are very unstable, being decomposed by 

 heating, especially by sterilizing under pressure. Lime juice 

 has been used for many years as an antiscorbutic. It is not 

 particularly rich in these substances, but in lime juice they 

 seem unusually stable. It has been suggested that the free 

 organic acid present in the lime juice protects the antiscorbutic 

 substances. 



It is therefore quite evident that the last decade has brought 

 forward many contributions of the greatest hygienic and economic 

 importance. It is quite certain that more important discoveries 

 are still to come. It is therefore well to look askance at popular 

 prophecies concerning the approaching inadequacy of the world's 

 food supply. When our viewpoint has changed so radically 

 in a few years, it is idle to speculate about the future. If I 

 have been able tonight to present this point to you clearly, 

 I have accomplished my purpose. 



