VITAMINS 231 



and it probably also is involved in the utilization of excess dietary pro- 

 tein as a source of energy. It is not apparently needed for the metab- 

 olism of fat, and the inclusion of a large amount of fat in the diet exerts 

 a thiamine-sparing action. In short, it may be said that the thiamine 

 requirement is related to the nonfat calories provided by the food con- 

 sumed. Abnormal conditions affecting the thiamine requirement of the 

 body have been considered on pp. 228 and 229. 



Table 9-3 



Daily human requirement for water soluble vitamins* 



Nicotinic Ascorbic 



Thiamine Riboflavin acid acid 



Subject mg. mg. mg. mg. 



Man (154 lb., 70 kg.) 



Moderately active 1.5 1.8 15 75 



Very active 1.8 1.8 18 75 



Sedentary \2 1.8 12 75 



Woman (123 lb., 56 kg.) 



Moderately active 1.2 1.5 12 70 



Very active 1.5 1.5 15 70 



Sedentary 1.0 1.5 10 70 



Pregnancy (latter half) 1.5 2.5 15 100 



Lactation 1.5 3.0 15 150 



Children 



Under 1 year 0.4 0.6 4 30 



1-3 years (27 lb., 12 kg.) 0.6 0.9 6 35 



4-6 years (42 lb., 19 kg.) 0.8 1.2 8 50 



7-9 years (58 lb., 26 kg.) 1.0 1.5 10 60 



10-12 years (78 lb., 35 kg.) 1.2 1.8 12 75 



Girls 



13-15 years (108 lb., 49 kg.) 1.3 2.0 13 80 



16-20 years (122 lb., 55 kg.) 1.2 1.8 12 80 



Boys 



13-15 years (108 lb., 49 kg.) 1.5 2.0 15 90 



16-20 years (141 lb., 64 kg.) 1.7 2.5 17 100 



* As recomended by the Food and Nutrition Boai'd of the National Research Council, 

 1948. 



Detailed estimates of the amount of thiamine needed daily by various 

 persons are shown in Table 9-3. For most people approximately 1-2 

 mg. daily constitute a safe intake. Quantities of representative foods 

 that would supply an amount within these limits are: 1 lb. brown rice, 

 4 lb. cabbage, 2 lb. asparagus, i/4 lb. lean pork chop, 2 qt. whole milk, 

 or 5 lb. white flour. If desired, the above amounts of thiamine may be 

 expressed as international units, on the basis that 3 /^g. of the pure vita- 

 min correspond to one unit. 



One of the largest dietary sources of thiamine, as well as of niacin and 

 riboflavin, would be bread and other grain products, except for the great 

 losses of these vitamins which occur on milling (Table 9-4). To com- 



