XII. FUTURE PROBLEMS 393 



e. Interrelations with Other Vitamins 



The relation of vitamin A to ascorbic acid synthesis requires further in- 

 vestigation with due consideration of such factors as food intake and pres- 

 ence or alit^ence in the diet of substances stimulatory to ascorbic acid syn- 

 thesis. Much remains to l)e done as to specificity of action of ascorbic acid 

 in its interrelations with other \-itamins, particularly with reference to 

 possible effects on enzyme action. 



/. Other Frublems 



We need to know much more about the amino acid and fat relations of 

 ascorbic acid under conditions of controlled food intake. Regardless of a 

 vast amount of work already completed in the field of enzyme and hormone 

 interrelations of the vitamin, not many, if any, of the problems have been 

 settled; hence opportunities for future investigation appear to remam lim- 

 itless. 



