Some spoil the most delicious watermelon by heaping sugar or salt, or both, upon it. In this way the flavor is lost. There is not a raw fruit on the market which is as finely flavored after it has been sugared as it was before. True, those who have ruined their sense of taste object to the tartness and natural acidity of various foods, but they are not judges and can not be until they have regained a normal taste, which can only be done by living on natural foods for a while.
Fats are obtained most plentifully from nuts, legumes, dairy products and animal foods. They are the most concentrated of all foods, yielding over twice the amount of heat or energy that we can obtain from the same weight of pure sugar, starch or protein. Many who think they are moderate eaters consume enough butter to put them in the glutton class.
Salts are present in all natural foods of which we partake.
Water is indispensable, for the body has to have fluids in order to perform its functions.
Foods are burned in the body. They are valuable in proportion to the completeness with which they are digested and assimilated and the ease with which this process is accomplished. It takes energy to digest food and if the food is very indigestible it takes too much energy.
The following remarks on digestibility are according to the best knowledge we have on the subject:
As a general rule, the protein of meat and fish is more completely and more quickly digested than the protein in vegetable foods. The reason is that the vegetable protein is found in cells which are protected by the indigestible cellulose which covers each cell. This covering is not always broken and then the digestive juices are practically powerless.
The legumes, which are rich in protein, are comparatively hard to digest. If properly prepared and eaten, they give little or no trouble, but they are generally cooked soft and the mastication is slighted. The result is fermentation. Beans, peas and lentils should be very well chewed, and eaten in moderation, for they are rich both in starch and protein.
Nuts are as a rule not as completely digested as meats and animal fats, and the principal reason is that they are eaten too rapidly and masticated too little. Nuts properly masticated, taken in correct combinations and amounts agree very well. It is not necessary, as many believe, to salt them in order to prevent indigestion.
In the following pages will be found a number of diet tables, giving compositions and fuel values of various foods which have been grouped for the sake of convenience, for the foods in each group are quite similar. These tables are not complete, for to list every food would take too much space. I have simply selected a representative list from the various classes of foods. Under flesh are given fish, meats and eggs. Under succulent vegetables are given both root and top vegetables, because of their similarity. Nuts, cereals, legumes, tubers and fruits are each grouped because it is easy to gain an understanding of them in this way. Milk is given a rather long chapter of its own because of its great importance in the morning of life.