THE STORY OF OUR FOODS 21 



case of obesity or corpulence, the diet treatment of 

 which excludes starches and sugars from the dietary 

 to as great an extent as possible, whilst the amount 

 of fatty foods need not be reduced to the same 

 degree. The liver appears to be an organ in which 

 the transformation of starchy foods into fats 

 specially takes place. When geese and ducks are 

 artificially fed upon maize (which contains a very 

 large proportion of starch), and are prevented from 

 taking due exercise, the livers of the birds become 

 masses of fat, which are used in the preparation of 

 the familiar pate de foie gras of Strasburg. 



OUR NOURISHMENT. One of the first rules for 

 healthy nutrition which may be deduced from what 

 we have learned regarding foods, is that both classes 

 of foods are required for the due nutrition and 

 support of the body, and this for the reason that the 

 one class of foods discharges different functions in 

 the frame from the other. The body-building foods 

 are not required in anything like the proportion of 

 the energy-producing ones. The comparison between 

 the engine and the body again holds good. The 

 engine in the performance of its work consumes 

 far more coal and water, as sources of energy- 

 production, than it requires iron for repairs, although 

 it must be confessed the human engine is somewhat 

 more imperious in its demands for the daily repair 

 of its substance than is the machine. The com- 

 parison, however, holds good so far in that day by 

 day we must consume a far larger amount of work- 

 producing foods than of those which contribute to 

 renew our bodily substance. Thus it has been 

 calculated that the proportions required in the case 

 of an adult man of the two foods are represented by 

 one of nitrogenous or body-building substance to 



