LESSON XIII
Simple Classification of Foods
While there is a dominating substance in all foods, yet they usually contain many compounds which render them, from a chemical standpoint, very difficult to classify accurately. For example, the principal nutrients in wheat are carbohydrates (starch and sugar), yet wheat contains mineral salts, fat, and protein, the latter being a compound consisting of carbon, hydrogen, oxygen, nitrogen, and sulfur. Wheat would, therefore, be placed in the carbohydrate class, but it would overlap into several other classes. What is true of wheat, is true of nearly all other articles of food. Furthermore, foods do not chemically reproduce themselves when taken into the body, but in the process of metabolism they are converted either into other elements or into other compounds. From this it will be understood that the articles listed under the following headings are classified according to the nutritive substance which predominates in them, and are given for the purpose of guiding the practitioner in the selection of such foods as will supply the various chemical constituents of the body.
Foods which contain two or more substances in generous proportions may appear under two or more of the following headings, as in the case of peanuts. This humble article of food contains 19 per cent carbohydrates, 20 per cent protein, and 29 per cent fat, hence it is listed under the three headings—carbohydrates, proteids, and fats.
The tables comprise the best selections of food available in all countries and at all seasons of the year. They contain everything the body needs under the varying conditions of age, climate, and activity, except, perhaps, in some parts of the frigid zone.
In compiling these tables I have selected only such articles of food as experience has proved most useful.
SIMPLE CLASSIFICATION OF FOODS BASED ON PRINCIPAL NUTRITIVE SUBSTANCES
| /——————Carbohydrates——————\ | Fats | Proteids | Foods rich in Mineral Salts | ||
|---|---|---|---|---|---|
| Chocolate | Honey | Vegetables— | Butter | Cheese | Vegetables— |
| Fruits— | Nuts— | Asparagus | Cheese | Eggs | Asparagus |
| Dates | Chestnuts | Bananas | Chocolate | Fish | Beet-tops |
| Figs | Peanuts | Beets | Cream | Legumes— | Cabbage |
| Grapes | Pignolia or | Cabbage | Nuts— | Beans—dried | Carrots |
| Persimmons | pine nuts | Carrots | Almonds | Lentils—dried | Celery |
| Raisins | Sirups | Celery | Brazil-nuts | Peas—dried | Dandelion |
| Grains— | Sugar | Lettuce | Cocoanuts | Milk | Green peas |
| Barley | Tapioca | Onions | Hickory-nuts | Nuts— | Lettuce |
| Corn | Parsnips | Peanuts | Peanuts | Onions | |
| Oats | Potatoes—sweet | Pecans | Pignolia or | Radish-tops | |
| Rice | Potatoes—white | Pignolia or | pine nuts | Romaine | |
| Rye | Pumpkin | pine nuts | Poultry | Spinach | |
| Wheat | Spinach | Walnuts | Vegetables— | String beans | |
| Squash | Oils— | Cabbage | Turnip-tops | ||
| Turnips | Cottonseed | Lettuce | Watercress | ||
| Nut-oil | Onions | Wheat bran | |||
| Olive-oil | Spinach | ||||
| Turnips | |||||
| Wheat bran | |||||