996 ANNUAL. REPORT OF THE Off. Doc. 



quired to raise one ton one foot. One calorie is equal very nearly 

 to 1.53 foot-tons. 



The following general estimate has been made for the average 

 amount of potential energy in one pound of each of the classes of 

 nutrients : 



Calories. 



In one pound of protein, 1,8G0 



In one pound of fats, 4,220 



In one pounds of carbohydrates, 1,860 



In other words, when we compare the nutrients in respect to their 

 fuel values, their capacities for yielding heat and mechanical power, 

 a pound of protein of lean meat or albumen of egg is just about 

 equivalent to a pound of sugar or starch, and a little over two 

 pounds of either would be required to equal a pound of the fat of 

 meat or butter or the body fat. 



Within recent years analyses of a large number of samples of 

 foods have been made in this country. In the table below the av- 

 erage results of a number of these analyses are given: 



