The true interpretation of the word "digestion" is the preparation of food by the action of:

1 The saliva

2 The gastric juice

3 The bile, and

4 The pancreatic juice

When food is properly prepared by mastication by the time it reaches the pancreas, it should be thoroughly split up or subdivided, in which state it is ready for assimilation.

The true interpretation of the word "assimilation" is the absorption of all food substances through the walls of the intestinal tract, and the final passing of them into the circulation.

It is nothing unusual, however, for a person to become afflicted with predigestion, and, at the same time, with poor or faulty assimilation; in other words, digestion being too rapid, and assimilation being too slow. This condition frequently occurs in cases of super-acidity. On account of the excess of acid, the food digests or passes from the stomach prematurely; that is, before it has been dissolved by the action of the hydrochloric acid. The food, thus super-charged with acid, passes from the stomach into the lower intestines, and sets up a condition of irritation. This irritation or swelling of the mucous surface (lining) of the intestines, closes the small canals, or winking valves, as they are sometimes called, thus seriously interfering with the passing of the dissolved food matter into the circulation.

The following table is designed to show the comparative assimilability of the leading articles of food, together with their starch, sugar, and water content:

Table Showing Comparative Assimilability And Carbohydrate And Water Content Of Cereals, Legumes, And Vegetables

*While all the vegetables mentioned in the above table belong to the carbohydrate class, yet the starch element contained in them is very much more assimilable than the starch contained in grains or legumes, therefore these vegetables may be eaten freely by those having rheumatic or gouty tendencies.

The starch and the sugar content in fresh vegetables appears low owing to the fact that they contain a large percentage of water. Eliminating the water, these foods rank in their starch and sugar content with cereals and legumes, and are much more easily digested and assimilated. In other words, if the chemist should reduce the water content to the same per cent as that of cereals, the carbohydrate content would rise in the same ratio as the water content is reduced. Both the starch and the sugar content of these vegetables is more digestible, and more readily assimilated than the starch and the sugar found in cereals and legumes.

Purpose Of The Vieno Table

The student should remember that not only the quantity but the quality of food must be considered. The vieno system of food measurement, as herein explained, is the simplest system of food measurement that has ever been published. It is amply complete, and accurate enough for the purpose for which it is intended, and that is the calculation of the energy and the available nitrogen contained in natural dietaries.

This measurement is really a quantitative measurement; that is, it measures the quantity, not the quality. In order to have a full knowledge of a bill of fare, it is necessary to know, in addition to the quantity, the exact chemical nature of each particular food, and also to know the other foods with which that food will combine.

This food table tells accurately the amount of energy that may be derived from food by chemical analysis, but it does not tell the amount of energy that the body must expend in the work of assimilation. This cannot be given in a table, because it varies with the individual and the condition of his digestive organs.