﻿592 
  ANNUAL 
  REPORT 
  SMITHSONIAN 
  INSTITUTION, 
  1943 
  

  

  nutrients; 
  and 
  (d) 
  vitamins. 
  In 
  addition 
  to 
  knowing 
  that 
  these 
  many 
  

   factors 
  are 
  necessary, 
  we 
  also 
  have 
  at 
  hand 
  some 
  information 
  bearing 
  

   on 
  the 
  question 
  of 
  how 
  much 
  food 
  the 
  average 
  person 
  needs, 
  and 
  the 
  

   factors 
  that 
  may 
  change 
  that 
  requirement. 
  Although 
  at 
  the 
  present 
  

   time 
  we 
  do 
  not 
  know 
  all 
  we 
  should 
  like 
  to 
  know 
  about 
  the 
  requirements 
  

   of 
  certain 
  dietary 
  essentials, 
  such 
  as 
  vitamins 
  B 
  x 
  and 
  B 
  2 
  , 
  we 
  already 
  

   have 
  a 
  body 
  of 
  knowledge 
  sufficiently 
  large 
  to 
  warrant 
  interesting 
  

   applications 
  not 
  merely 
  to 
  a 
  civilian 
  peace-time 
  population 
  but 
  an 
  ever- 
  

   growing 
  armed 
  force 
  as 
  well. 
  All 
  this 
  information 
  has 
  been 
  used 
  in 
  

   planning 
  the 
  commissary 
  of 
  our 
  armed 
  forces. 
  In 
  other 
  words, 
  the 
  

   modern 
  science 
  of 
  nutrition 
  enables 
  us 
  to 
  deal 
  with 
  this 
  new 
  world- 
  

   wide 
  food 
  problem 
  in 
  far 
  more 
  effective 
  fashion 
  than 
  was 
  ever 
  before 
  

   possible. 
  

  

  For 
  about 
  10 
  years, 
  the 
  Chicago 
  Quartermaster 
  Depot 
  of 
  the 
  United 
  

   States 
  Army 
  has 
  maintained 
  what 
  is 
  called 
  the 
  Subsistence 
  Research 
  

   Laboratory 
  devoted 
  to 
  the 
  application 
  of 
  this 
  modern 
  knowledge 
  in 
  

   the 
  practical 
  solution 
  of 
  army 
  food 
  problems. 
  The 
  older 
  standard 
  

   rations 
  have 
  been 
  examined 
  in 
  the 
  light 
  of 
  the 
  new 
  developments 
  and 
  

   appropriate 
  changes 
  made. 
  Numerous 
  new 
  rations 
  designed 
  to 
  fit 
  

   special 
  situations 
  in 
  the 
  field 
  have 
  been 
  devised. 
  The 
  question 
  

   whether 
  the 
  good 
  standard 
  army-post 
  ration 
  in 
  common 
  use 
  in 
  this 
  

   country, 
  known 
  to 
  contain 
  ample 
  supplies 
  of 
  vitamins 
  and 
  other 
  

   essential 
  factors, 
  would 
  be 
  improved 
  by 
  supplementation 
  with 
  vitamin 
  

   tablets 
  has 
  been 
  put 
  to 
  scientific 
  test 
  with 
  soldiers 
  under 
  properly 
  

   controlled 
  experimental 
  conditions. 
  The 
  answer 
  to 
  this 
  particular 
  

   question 
  proves 
  to 
  be 
  negative. 
  It 
  does 
  not 
  necessarily 
  follow 
  from 
  

   this 
  that 
  the 
  provision 
  of 
  an 
  unusual 
  and 
  extra 
  supply 
  of 
  one 
  or 
  more 
  

   vitamins 
  to 
  soldiers 
  never 
  serves 
  any 
  useful 
  purpose. 
  As 
  yet 
  too 
  few 
  

   of 
  the 
  special 
  work 
  situations 
  of 
  interest 
  have 
  really 
  been 
  investigated 
  

   from 
  this 
  point 
  of 
  view. 
  In 
  another 
  study, 
  carried 
  out 
  in 
  a 
  university 
  

   laboratory, 
  where 
  men 
  subjected 
  themselves 
  to 
  extreme 
  muscular 
  work 
  

   to 
  the 
  point 
  of 
  exhaustion, 
  it 
  was 
  found 
  that 
  their 
  endurance 
  of, 
  and 
  

   ease 
  of 
  recovery 
  from, 
  the 
  severe 
  strain 
  was 
  related 
  to 
  their 
  receiving 
  

   daily 
  a 
  liberal 
  supply 
  of 
  a 
  natural 
  source 
  of 
  the 
  vitamin 
  B 
  complex 
  

   (such 
  as 
  dried 
  yeast) 
  ; 
  daily 
  administration 
  of 
  a 
  supply 
  of 
  vitamin 
  Bi 
  

   alone 
  was 
  not 
  as 
  effective. 
  In 
  still 
  another 
  study, 
  evidence 
  has 
  been 
  

   obtained 
  that 
  two 
  of 
  the 
  most 
  recently 
  discovered 
  members 
  of 
  the 
  

   vitamin 
  B 
  complex 
  are 
  of 
  some 
  importance 
  in 
  relation 
  to 
  muscular 
  

   fatigue 
  and 
  recovery 
  from 
  vigorous 
  exercise. 
  Numerous 
  investiga- 
  

   tions 
  relating 
  to 
  this 
  general 
  problem 
  are 
  being 
  carried 
  on 
  in 
  the 
  

   laboratories 
  of 
  the 
  country 
  as 
  part 
  of 
  our 
  research 
  contribution 
  to 
  

   winning 
  the 
  war. 
  

  

  Earlier 
  in 
  this 
  article 
  the 
  factors 
  important 
  in 
  nutrition 
  were 
  

   classified. 
  The 
  first 
  one 
  to 
  be 
  mentioned 
  was 
  energy. 
  The 
  need 
  for 
  

  

  