238 QUALITY OF FOOD. 



Disease, habit, the mental state and many other things exert an 

 influence on the state of the appetite, 



It is true that Dr. Beaumont noticed, in his experiments upon 

 Alexis St. Martin, that after a certain amount of food had been con- 

 verted into chyme the gastric juice ceased to ooze from the coats of 

 the stomach, and it has consequently been inferred by some medi- 

 cal writers that the glands which supply this juice would only sup- 

 ply enough for the actual wants of the system. But what are the 

 reasonable grounds of this inference? Can anyone show a reason 

 why the gastric glands may not be stimulated to extra activity or be 

 influenced by habit as well as other organs? 



It is admitted that the predisposing cause of hunger is usually 

 a demand of the system for nutrient material; but it is also insisted 

 that this is not always the immediate cause of the sensation of hun- 

 ger. Some physicians ascribe it to certain conditions of the glands 

 of the stomach, and others to a peculiar state of the nervous sys- 

 tem. 



QUALITY OF FOOD. 



Generalities The kind of food best adapted to the wants 

 of the system is modified by many circumstances. The different 

 varieties of food are still further modified by the various methods 

 of preparation. A given quality of food is not equally well adapted 

 to different individuals, or to the same individual in different condi- 

 tions. This must be obvious to all who have even slightly observed 

 the effect of the same food, at different times, upon themselves. 



What is Meant by Quality in Food Food is either uu- 

 tritive or digestible, but a single article is not necessarily both. 

 Foods are nutritious in proportion as they supply the elements of 

 chyle, but they are digestible only in proportion to the readiness 

 with which they yield to the action of the gastric juice. These 

 properties should not be confounded. Such articles as milk and 

 eggs which contain the greatest amount of the constituent elements 

 or the system are most nutritious, but there are conditions of the 

 system in which these are wholly indigestible. Of course those 

 articles which do not contain the essential elements of the system 

 should never form the exclusive diet. On the other hand it is plain 

 that articles which contain but a small quantity of these elements 

 may often afford the greatest amount of nourishment because they 

 are more easily digested. 



Time of Digestion To ascertain the time required for the 

 digestion of the different articles of food, Dr. Beaumont made 

 many experiments on Alexis St. Martin, the general results of which 

 are shown in the following table. As is known to almost every one, 

 the stomach of St. Martin was ruptured by the bursting of a gun. 

 He recovered under Dr. Beaumont's care, when the stomach adhered 

 to the side, with an external opening. In the healing process 



