B VITAMIN DEFICIENCY STATES 



405 



problems of thiamine and riboflavin nutrition in gerontology and mental 

 disease, it is one of the major contributions to the literature on the subject 

 of vitamin deficiency, and may well serve as a model for further studies 

 of this nature, much needed with regard to nonclinical individuals and 

 cases involving the remainder of the B vitamin group. 



a 



10 15 20 25 5 10 15 20 



Days on Thiamine Deficient Diet 



Figure 17. Decline in urinary and tissue levels of thiamine during the course of 

 thiamine depletion in the rat. 



Previous mention has been made of the fact that in thiamine restriction, 

 the rapid drop in urinary thiamine is followed by a much more gradual 

 decline in tissue levels. Salsedo et al. 59 have studied these changes in 

 thiamine-deficient rats, and their results are summarized in Figure 17. 

 These workers have suggested that the drop in tissue levels coinciding 



