472 
The  Truth  About  Vitamines. 
Am.  Jour.  Pharm, 
July,  1920. 
We  have  seen  that  the  absence  from  a  diet  of  any  one  of  the  tliree 
vitamines  gives  rise  to  a  corresponding  disorder:  The  absence  of 
vitamine  A  causes  rickets,  of  B  beri-beri,  and  of  C  scurvy.  Now, 
there  is  good  evidence  for  beHeving  that  another  disease,  pellagra, 
which  is  endemic  in  Northern  Italy,  Roumania,  and  in  certain  parts 
of  North  America,  is  due  to  the  absence  of  four  food  factors — two 
of  them  vitamines — though  whether  all  four  "absences"  have  to 
be  present  together  or  only  in  pairs  is  a  point  not  yet  solved.  The 
four  pellagra-producing  factors  are  these:  (i)  Shortage  of  vitamine 
A;  (2)  shortage  of  vitamine  B;  (3)  shortage  of  inorganic  salts ; 
(4)  shortage  of  proteins.  It  is  at  any  rate  certain  that  no  one 
factor  alone  can  produce  pellagra,  but  that  at  least  two  of  them 
together  must  be  present.  The  symptoms  of  pellagra  are  gastro- 
intestinal disturbances  and  bilateral  symmetrical  dermatitis.  But 
the  whole  subject  of  the  relation  of  vitamines  to  disease  is  in  its 
infancy.  The  question  of  pellagra,  by  offering  a  combination  of 
causes,  opens  up  a  complicated  field  for  research. 
The  most  astonishing  thing  about  vitamines  is  that  they  are 
apparently  non-existent.  We  are  often  told,  somewhat  loftily, 
that  "vitamines  have  not,  as  yet,  been  isolated."  This  is  only  a 
part  of  the  truth.  The  whole  truth  is  that  their  existence  has  not  yet 
been  demonstrated.  If  this  declaration,  coming  at  the  end  of  an 
article  on  vitamines,  sounds  paradoxical,  I  must  add  a  word  or 
two  in  explanation.  We  have  seen  that  butter  differs  from  vegetable 
margarine  in  certain  important  particulars.  Butter  has  properties 
which  margarine  has  not.  But  this  fact,  indisputable  as  it  is,  is  a 
long  way  from  warranting  the  conclusion  that  butter  =  margarine 
+  vitamine.  Tartaric  acid  has  a  property  ("optical  activity"  is  it 
called)  which  racemic  acid  has  not,  and  both  acids  are  chemically 
identical.  But  this  fact  does  not  warrant  us  in  saying  that  tartaric 
acid  contains  "opticamine,"  while  racemic  acid  does  not.  The  truth 
is  that  tartaric  and  racemic  acids  are  isomeric,  and  are  identical  in 
every  way  except  as  to  the  arrangement  of  their  atoms  within  the 
molecule.  A  similar  hypothesis  seems  preferable  to  explain  the 
important  differences  between  the  glyceryl  oleate,  etc.,  which  we 
call  butter,  and  the  same  chemical  compounds  which  we  call  mar- 
garine. It  is  an  indispensable  rule,  in  framing  hypothesis  to  explain 
phenomena,  not  to  go  beyond  what  is  warranted  by  data.  The 
Law  of  Parsimony  applies  here.  That  hypothesis  should  be  chosen 
which  follows  the  most  closely  on  the  heels  of  the  facts,  which  puts 
