478 THIAMINE 



maximal cocarboxylase content of these tissues twice the amount is re- 

 quired as is needed for normal growth. We cannot tell whether this maximal 

 intake of thiamine has any advantage for the animal or not. 



B. OF MAN 

 W. H. SEBRELL, JR. 



The principal factors influencing thiamine requirements are the carbo- 

 hydrate and the calorie intake. The requirement for thiamine is reduced 

 when fat forms a large part of the diet, but for practical purposes the 

 thiamine need may be based on the total calorie intake. 



An early appraisal of the thiamine requirements of man was made by 

 CowgilP in 1934. This appraisal was based on an analysis of dietary data 

 in the literature in relation to the occurrence of beriberi. On the basis of 

 this data the minimum intake of thiamine necessary to prevent beriberi is 

 not less than 0.28 mg. per 1000 cal. (60-kg. man on 2500 cals.) or a total 

 per day of 0.7 mg. 



Elsom et al^^ in a study on women volunteers concluded that 0.65 mg. 

 per day was the minimum intake necessary to maintain health. 



Melnick,^* using saturation tests, reported that adults required 0.35 mg. 

 per 1000 cal. or 0.875 mg. per day on a 2500-cal. diet. 



Williams et al}^ found that an intake of 0.22 mg. of thiamine per 1000 

 cal. caused a slow depletion of tissue reserves and with an intake of 0.45 

 mg. per 1000 cal. there was a slight depletion of cocarboxylase. 



Keys et al}^ studied the performance of normal young men on controlled 

 thiamine intakes and found that for a period of 10 to 12 weeks no benefit 

 of any kind was observed with intakes of more than 0.23 mg. of thiamine 

 per 1000 cal. (intake 3050 ± 200 cal. per day). 



In 1944 Holt^^ critically reviewed the studies of experimental thiamine 

 deficiency by Williams, Elsom, Keys, and Najjar and their collaborators 

 and reinterpreted the data to conclude that the minimum thiamine require- 

 ment of an adult man on a diet of natural foods lies between 0.17 and 0.23 

 mg. per 1000 cal. He concludes that a range of intake between 0.24 mg. 

 and 0.44 mg. per 1000 cal. appears to protect against thiamine deficiency. 



Oldham et al}^ found no change in blood thiamine levels with intakes 

 above 0.2 mg. per 1000 cal. 



« K. O'S. Elsom, J. G. Rhoiiihold, J. T. L. Nicholson, :ind C. Choniocli, Am. J. 



Med. Sci. 203, 569 (1942). 

 ■" D. Mehiick, ./. Nutrition 24, 139 (1942). 



s» R. T). Williams, H. L. Mason, and R. M. WildcM-. ./. Xntrilion 25, 71 (1943). 

 " A. Keys, A. F. TIensohol, O. Mickolsen, and J. M. Hrozck, /. Ni)liitit»n 26, 399 



(1943)". 

 ^2 L. E. Holt, Jr., Federation Proc. 3, 171 (1944). 

 " H. G. Oldham, M. V. Davis, and L. J. Roberts, /. Nutrition 32, 163 (1944). 



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