Table V.—Standards for Dietaries. Available Nutrients and Energy per Man per Day.
| Protein. | Fat. | Carbo- hydrates. | Fuel Value. | |
| Voit’s Standards. | Grams.[9] | Grams. | Grams. | Calories. |
| Man at hard work | 133 | 95 | 437 | 3270 |
| Man at moderate work | 109 | 53 | 485 | 2965 |
| Atwater’s Standards. | ||||
| Man at very hard muscular work | 161 | · ·[10] | · ·[10] | 5500 |
| Man at hard muscular work | 138 | · · | · · | 4150 |
| Man at moderately active muscular work | 115 | · · | · · | 3400 |
| Man at light to moderate muscular work | 103 | · · | · · | 3050 |
| Man at “sedentary” or woman at moderately active work | 92 | · · | · · | 2700 |
| Woman at light muscular work, or man without muscular exercise | 83 | · · | · · | 2450 |
8. Hygienic Economy of Food.—For people in good health, there are two important rules to be observed in the regulation of the diet. One is to choose the foods that “agree” with them, and to avoid those which they cannot digest and assimilate without harm; and the other is to use such sorts and quantities of foods as will supply the kinds and amounts of nutrients needed by the body and yet to avoid burdening it with superfluous material to be disposed of at the cost of health and strength.
As for the first-mentioned rule, it is practically impossible to give information that may be of more than general application. There are people who, because of some individual peculiarity, cannot use foods which for people in general are wholesome and nutritious. Some persons cannot endure milk, others suffer if they eat eggs, others have to eschew certain kinds of meat, or are made uncomfortable by fruit; but such cases are exceptions. Very little is known regarding the cause of these conditions. It is possible that in the metabolic processes to which the ingredients of the food are subjected in the body, or even during digestion before the substances are actually taken into the body, compounds may be formed that are in one way or another injurious. Whatever the cause may be, it is literally true in this sense that “what is one man’s meat is another man’s poison,” and each must learn for himself what foods “agree” with him and what ones do not. But for the great majority of people in health, suitable combinations of the ordinary sorts of wholesome food materials make a healthful diet. On the other hand, some foods are of particular value at times, aside from their use for nourishment. Fruits and green vegetables often benefit people greatly, not as nutriment merely, for they may have very little actual nutritive material, but because of fruit or vegetable acids or other substances which they contain, and which sometimes serve a most useful purpose.
Table VI.—Amounts of Nutrients and Energy Furnished for One Shilling in Food Materials at Ordinary Prices.
| Food Materials as Purchased. | Prices per ℔ | One Shilling will buy | ||||
| Total Food materials. | Available Nutrients. | Fuel Value. | ||||
| Protein. | Fat. | Carbo- hydrates. | ||||
| s. d. | ℔ | ℔ | ℔ | ℔ | Calories. | |
| Beef, round | 0 10 | 1.20 | .22 | .14 | · · | 1,155 |
| 0 8½ | 1.41 | .26 | .17 | · · | 1,235 | |
| 0 5 | 2.40 | .44 | .29 | · · | 2,105 | |
| Beef, sirloin | 0 10 | 1.20 | .19 | .20 | · · | 1,225 |
| 0 9 | 1.33 | .21 | .22 | · · | 1,360 | |
| 0 8 | 1.50 | · · | · · | · · | · · | |
| 0 5 | 2.40 | · · | · · | · · | · · | |
| Beef, rib | 0 9 | 1.33 | .19 | .19 | · · | 1,200 |
| 0 7½ | 1.60 | · · | · · | · · | · · | |
| 0 4½ | 2.67 | · · | · · | · · | · · | |
| Mutton, leg | 0 9 | 1.33 | .20 | .20 | · · | 1,245 |
| 0 5 | 2.40 | .37 | .35 | · · | 2,245 | |
| Pork, spare-rib | 0 9 | 1.33 | .17 | .31 | · · | 1,645 |
| 0 7 | 1.71 | .22 | .39 | · · | 2,110 | |
| Pork, salt, fat | 0 7 | 1.71 | .03 | 1.40 | · · | 6,025 |
| 0 5 | 2.40 | .04 | 1.97 | · · | 8,460 | |
| Pork, smoked ham | 0 8 | 1.50 | .20 | .48 | · · | 2,435 |
| 0 4½ | 2.67 | .36 | .85 | · · | 4,330 | |
| Fresh cod | 0 4 | 3.00 | .34 | .01 | · · | 710 |
| 0 3 | 4.00 | .45 | .01 | · · | 945 | |
| Salt cod | 0 3½ | 3.43 | .54 | .07 | · · | 1,370 |
| 0 10 | 1.20 | .07 | .01 | .04 | 275 | |
| Milk, whole, 4d. a qt. | 0 2 | 6.00 | .19 | .23 | .30 | 1,915 |
| ” 3d. a qt. | 0 1½ | 8.00 | .26 | .30 | .40 | 2,550 |
| ” 2d. a qt. | 0 1 | 12.00 | .38 | .46 | .60 | 3,825 |
| Milk, skimmed, 2d. a qt. | 0 1 | 12.00 | .40 | .03 | .61 | 2,085 |
| Butter | 1 6 | .67 | .01 | .54 | · · | 2,320 |
| 1 3 | .80 | .01 | .64 | · · | 2,770 | |
| 1 0 | 1.00 | .01 | .81 | · · | 3,460 | |
| Margarine | 0 4 | 3.00 | · · | 2.37 | · · | 10,080 |
| Eggs, 2s. a dozen | 1 4 | .75 | .10 | .07 | · · | 475 |
| ” 1½s. a dozen | 1 0 | 1.00 | .13 | .09 | · · | 635 |
| ” 1s. a dozen | 0 8 | 1.50 | .19 | .13 | · · | 950 |
| Cheese | 0 8 | 1.50 | .38 | .48 | .04 | 2,865 |
| 0 7 | 1.71 | .43 | .55 | .04 | 3,265 | |
| 0 5 | 2.40 | .60 | .77 | .06 | 4,585 | |
| Wheat bread | 0 11⁄8 | 10.67 | .76 | .13 | 5.57 | 12,421 |
| Wheat flour | 0 13⁄5 | 7.64 | .67 | .07 | 5.63 | 12,110 |
| 0 1½ | 8.16 | .72 | .07 | 6.01 | 12,935 | |
| Oatmeal | 0 12⁄5 | 8.39 | 1.11 | .54 | 5.54 | 14,835 |
| 0 1½ | 8.16 | 1.08 | .53 | 5.39 | 14,430 | |
| Rice | 0 1¾ | 6.86 | .45 | .02 | 5.27 | 10,795 |
| Potatoes | 0 02⁄3 | 18.00 | .25 | .02 | 2.70 | 5,605 |
| 0 0½ | 24.00 | .34 | .02 | 3.60 | 7,470 | |
| Beans | 0 2 | 6.00 | 1.05 | .10 | 3.47 | 8,960 |
| Sugar | 1 ¾ | 6.86 | · · | · · | 6.86 | 12,760 |
The proper observance of the second rule mentioned requires information regarding the demands of the body for food under different circumstances. To supply this information is one purpose of the effort to determine the so-called dietary standards mentioned above. It should be observed, however, that these are generally more applicable to the proper feeding of a group or class of people as a whole than for particular individuals in this class. The needs of individuals will vary largely from the average in accordance with the activity and individuality. Moreover, it is neither necessary nor desirable for the individual to follow any standard exactly from day to day. It is requisite only that the average supply shall be sufficient to meet the demands of the body during a given period.
The cooking of food and other modes of preparing it for consumption have much to do with its nutritive value. Many materials which, owing to their mechanical condition or to some other cause, are not particularly desirable food materials in their natural state, are quite nutritious when cooked or otherwise prepared for consumption. It is also a matter of common experience that well-cooked food is wholesome and appetizing, whereas the same material poorly prepared is unpalatable. There are three chief purposes of cooking; the first is to change the mechanical condition of the food. Heating changes the structure of many food materials very materially, so that they may be more easily chewed and brought into a condition in which the digestive juices can act upon them more freely, and in this way probably influencing the ease and thoroughness of digestion. The second is to make the food more appetizing by improving the appearance or flavour or both. Food which is attractive to the eye and pleasing to the palate quickens the flow of saliva and other digestive juices and thus aids digestion. The third is to kill, by heat, disease germs, parasites or other dangerous organisms that may be contained in food. This is often a very important matter and applies to both animal and vegetable foods. Scrupulous neatness should always be observed in storing, handling and serving food. If ever cleanliness is desirable it must be in the things we eat, and every care should be taken to ensure it for the sake of health as well as of decency. Cleanliness in this connexion means not only absence of visible dirt, but freedom from undesirable bacteria and other minute organisms and from worms and other parasites. If food, raw or cooked, is kept in dirty places, peddled from dirty carts, prepared in dirty rooms and in dirty dishes, or exposed to foul air, disease germs and other offensive and dangerous substances may easily enter it.
9. Pecuniary Economy of Food.—Statistics of economy and of cost of living in Great Britain, Germany and the United States show that at least half, and commonly more, of the income of wage-earners and other people in moderate circumstances is expended for subsistence. The relatively large cost of food, and the important influence of diet upon health and strength, make a more widespread understanding of the subject of dietetics very desirable. The maxim that “the best is the cheapest” does not apply to food. The “best” food, in the sense of that which is the finest in appearance and flavour and which is sold at the highest price, is not generally the most economical.
The price of food is not regulated largely by its value for nutriment. Its agreeableness to the palate or to the buyer’s fancy is a large factor in determining the current demand and market price. There is no more nutriment in an ounce of protein or fat from the tender-loin of beef than from the round or shoulder. The protein of animal food has, however, some advantage over that of vegetable foods in that it is more thoroughly, and perhaps more easily, digested, for which reason it would be economical to pay somewhat more for the same quantity of nutritive material in the animal food. Furthermore, animal foods such as meats, fish and the like, gratify the palate as most vegetable foods do not. For persons in good health, foods in which the nutrients are the most expensive are like costly articles of adornment. People who can well afford them may be justified in buying them, but they are not economical. The most economical food is that which is at the same time most healthful and cheapest.