An Ideal Ration of Liquid Food.—(Mrs. E. H. Richards.) While diet-lists are easily prepared according to the method just outlined, it must always be remembered that the digestibility and absorbability of food play a most important rôle, and are not to be neglected in formulating the dietary; for while a certain food may contain a great many more calories than an equal weight of another food, yet its relative indigestibility and non-absorbability may render it far less available as an article of diet. For example, while 4 ounces of sausage produce 510 calories, 4 ounces of cheese 520, and 4 ounces of beef only 280, yet the beef is far more digestible than either the sausage or cheese, and thus more valuable as an article of food. As has been aptly said, "We live not upon what we eat, but upon what we digest.' Therefore, a diet-list giving quantities of food principles or calories is useful only as it suggests general principles that may be modified to meet individual conditions in health and in disease. The following table of Roberts will be found of value in computing diet: 1 According to how the rice is given. Jour. of the Amer. Med. Assoc., April 21, 1906. The Calorie Value of Common Foods per Ounce. (Meat, fish, and cereals are cooked. Vegetables are boiled.) System of Diet and Dietetics: THE INFLUENCE OF VARIOUS FACTORS UPON THE DIGESTION. Apart from the selection of a proper diet, important factors that especially affect the digestion are the following: 1. The hours, order, and frequency of meals. 2. Variety in diet. 3. The appetite. 4. The temperature of food. 5. Rest and exercise before and after meals. 6. Emotion. 1. Order and Frequency of Meals.-It is usually customary to fix certain hours for the taking of meals; these hours vary with the occupation of the individual. In large cities, where the noon hour is taken up largely with active business pursuits, evening is selected as the most convenient hour for dinner. Sir Henry Thompson states that three general systems are in use, according to which, two, three, or four meals are taken daily. The first system, which consists of two meals a day, is followed in France and other countries on the continent of Europe. A substantial meal, consisting of fish or meat and other courses of solid foods, is eaten about noon; no food is taken before the noon meal, except on arising, when a cup of coffee or chocolate and a small quantity of bread and butter are taken. The second meal, which is dinner, is eaten between 6 and 7 o'clock in the evening. This meal is the largest meal of the day, and consists of soup, fish, meat, vegetables, salads, dessert, and black coffee. The second system, commonly in vogue in England, consists of four meals daily. The first meal, or breakfast, is taken at about 8 A. M., and consists of cocoa, tea, or coffee, bread, butter, bacon, fish, or eggs; dinner is eaten between 1 and 2, and consists of soup, meat, fish, vegetables, and pudding; tea is taken at 5 P. M., and supper is served at 8, and consists of meat, fish, vegetables, and stewed fruits. Dinner is taken in the evening by the well-to-do classes, and a substantial lunch is usually taken at noon. The third system, practised in the United States, consists in taking three meals daily. In many towns it is customary to dine at noon; in others, in the evening. The usual breakfast, taken between 7 and 8 A. M., consists of fruits, breakfast food or cereals, eggs, bacon, or salt fish, tea, cocoa or coffee, and bread and butter. Luncheon, eaten between 12.30 and 2 o'clock, consists of cold meat or a chop, vegetables, salads, and dessert. Dinner, eaten between 6.30 and 8 P. M., is the heaviest meal of the day, and consists of soup, fish, meats, vegetables, salads, and fruit. The conventional order of taking food at dinner appears to be most rational, namely, soup, fish, entrée, meat, vegetables, salads, fruits. Small quantities of soup stimulate the gastric secretion, do not interfere with digestion, and pass rapidly from the stomach; the fish and entrée are then partaken of, before the acidity of the gastric secretion has reached its height; next follows the meat, the stomach now secreting liberal quantities of gastric juice wherewith to carry on the digestive processes; finally come the carbohydrates, which do not undergo digestion in the stomach, and which enter this organ when the food already taken is about to pass from the stomach into the intestine. The eating of bountiful dinners, made up of many courses, when frequently indulged in, is likely to lead to digestive disturbances. Children and invalids should always eat dinner at midday, between 12 and 2 o'clock, and should never be allowed to take this meal at night. The frequency of meals must be regulated according to individual conditions. Patients suffering from digestive disturbances and those who take very small quantities of food at a time require nourishment at frequent and regular intervals; whereas those whose digestion is feeble, should allow six or seven hours to elapse between meals; ordinarily the interval between meals should be about four or five hours, this being about the time necessary for complete digestion of a mixed meal in the stomach. The habit of habitually omitting the noon luncheon, so commonly practised by busy Americans, should be discouraged. 2. Variety in Diet.-In order thoroughly to satisfy the needs of the body the diet must be varied. Although a diet restricted to but a few articles of food may contain a sufficient quantity of the alimentary principles to sustain the body nutrition, yet the monotony of such a diet becomes so objectionable that it can not be digested thoroughly. According to Woods and Merrill, "it is a matter of common observation that digestion experiments made with one kind of food-material do not give on the whole as reliable results as those in which two or more food-materials are used. In other words, it appears that with a mixed diet the same person will digest a larger proportion of nutrients than with a diet composed of a single food-material." Certain races restrict the variety of food from religious motives, such as the Jewish restriction of ham, pork, and oysters. (See Levitcus, chapter xi.) 3. Appetite.-Appetite is the desire for food, and is dependent upon various conditions. It is controlled by the sensation of hunger, and is often induced by the sight, smell, 1 United States Department of Agriculture Bulletin No. 85. |