32 THECUBAREVIEW 



FOOD VALUE OF SUGAR 



The most interesting use of sugar is as a food for the animal body. Within certain limits, 

 sugar may be considered as the equivalent of starch that has been digested and made ready 

 for absorption. A mealy boiled potato, Uke all forms of starchy food, must be largely con- 

 verted into some kind of sugar by the digestive juices before it can be absorbed as food. 



It is commonly stated that the food eaten by the average adult is at least one-half of vege- 

 table origin, and analyses show that the nutrients of vegetable foods are very largely starch. 

 The average of 400 dietary studies made in the United States shows about 40 per cent animal 

 food and 60 per cent vegetable food. Starch in cereal grains and other foods, and separated 

 as cornstarch, etc., furnishes a considerable part of the heat and muscular power of the body. 

 The summary of data regarding the American diet quoted above shows that sugar constitutes 

 5.4 per cent of the average diet and furnishes 17.5 per cent of the total energy in it. It ia 

 clear that starch, sugar, or any food that will serve the same purpose is of great importance. 



To understand the utiUzation of such foods in the body better, the process of carbohy- 

 drate digestion may be considered. When a starchy food, such as boiled potato, is taken 

 into the mouth, it is at once acted upon more or less by a ferment contained in the saliva, and 

 this action is continued by a ferment contained in the intestines. It is broken up into simpler 

 chemical compounds, and it finally reaches the blood and muscles as dextrose, a form of sugar 

 which can be burned in the body to yield muscular energy and heat. When an excess of car- 

 bohydrates (sugar or starch) is consumed, the dextrose in the digestive tract is converted in 

 the liver to glycogen and stored until required, being then, it is beheved, reconverted into 

 dextrose. More complex changes may take place which convert carbohydrates consumed 

 in excess into fat, which is also stored as a reserve material. 



Some recent German investigations indicate that the different kinds of sugar are not 

 equally well adapted to increasing the supply of glycogen in the body. In experiments with 

 dogs, sucrose and dextrose proved the most valuable in this respect. 



DIGESTION OF SUGAR 



When sugar is eaten it is changed in the digestive tract before it is taken up in the blood 

 and carried where it is needed. If a solution of cane sugar be injected directly into the blood, 

 it is passed out by the kidneys unchanged, showing that it is not fitted for assimilation until 

 it has been changed, as it is in normal digestion. The change needed is slight compared with 

 that required for the digestion of starch, sugar being "inverted" or changed into the simpler 

 sugars as already described, and this change is brought about in the digestive tract 

 by the agency of enzyms or ferments regarding the nature of which Uttle is known. When 

 thus changed into the simpler sugars, its function in the body is similar to that of starch after 

 it has reached the analogous stage in digestion. 



At the Minnesota Experiment Station (i) the thoroughness of digestion of sugar was studied 

 with healthy men, 5 ounces per day being consumed as part of a simple mixed diet. The sugar 

 showed a high digestibility, 98.9 per cent of its total energy being available to the body, on 

 the average. In general, it increased the available energy of the whole ration 25 per cent 

 and did not affect the digestibility of the foods with which it was combined. The protein 

 of the ration was more economically used than commonly, the nitrogen retention being in- 

 creased 25 per cent. It was pointed out in discussing these experiments that "the value of 

 sugar in a ration depends upon its judicious use and combination with other foods." 



t Minnesota Sta. Rpt. 1903-4. 



{Continued.) 



JANUARY TRADE Month of January 



America's exports to Cuba in January and 1918 1917 

 the seven months ended with January have 



been announced by the Bureau of Foreign Exports to Cuba. . $18,629,850 $15,341,899 



and Domestic Commerce, Department of 7 months ended with J anwary 



Commerce. Exports to Cuba.. $130,984,164 $110,234,146 



