LOW PROTEIN DIETARY IN THE TROPICS 159 



the blood, it may fairly be deduced that the diet poor in nitrogen 

 is the cause of the deficiencies. The blood in chronic under- 

 feeding is said not to show, as a rule, any great variations in 

 composition, being able to maintain its normal state under very 

 adverse circumstances ; but the changes that do occur are all 

 of the same type as those discovered in the blood of the Bengali. 

 V. Hoesslin states that chronic under- feeding influences the 

 total volume of the blood, as well as the mass of all the tissues, 

 and produces individuals who are poorly supplied with blood, 

 fat, and muscle. 



It may, therefore, be concluded from these analyses that the 

 Bengali falls short of the European standards. His nitrog- 

 enous tissues are not given the option of drawing their 

 nutritive material from so rich a source, nor have they the 

 same opportunity of obtaining as free a supply of oxygen. 

 The effects of these conditions must be to modify very 

 markedly the physiological requirements of nutrition, and to 

 a considerable extent affect the growth, power of muscular con- 

 traction, and general metabolism of the individuals of such a 

 community. 



While it is impossible to state dogmatically that these differ- 

 ences are entirely due to an insufficient supply of protein in the 

 food, it would appear to be the most plausible, and, so far as the 

 facts go, the only explanation. 



We think we are justified in saying that a people who excrete 

 only 6 grammes of nitrogen daily in the urine live in a chronic 

 state of nitrogenous starvation, leading to a loss of body fat and 

 tissue protein, with the inevitable result of loss of vigour and 

 strength, and a comparatively low capacity for prolonged or 

 sustained muscular effort. 



Extracts from the older writers have been already given 

 bearing on the working capacity of a rice-fed people, and we shall 

 have further evidence to produce on this subject. At present it 

 will be sufficient to state that the Bengali falls far short of the 

 ordinary European in this respect. 



This is not due to any deficiency in the energy-producing 

 carbonaceous material, in which element their diet is very rich. 

 We hold, on the other hand, that it is due to a lack of muscular 

 development, and to the lower condition of vitality that must 

 follow from the presence of a composition of the blood ex- 

 hibiting the lower physiological limits of such necessary con- 



