SIXTY GRAMS OF PROTEID ARE CONTAINED IN
Fuel Value* | ||
| One-half pound fresh lean beef, loin | 308 | calories |
| Nine hens’ eggs | 720 | |
| Four-fifths pound sweetbread | 660 | |
| Three-fourths pound fresh liver | 432 | |
| Seven-eighths pound lean smoked bacon | 1820 | |
| Three-fourths pound halibut steak | 423 | |
| One-half pound salt codfish, boneless | 245 | |
| Two-and one-fifth pounds oysters, solid | 506 | |
| One-half pound American pale cheese | 1027 | |
| Four pounds whole milk (two quarts) | 1300 | |
| Five-sixths pound uncooked oatmeal | 1550 | |
| One and one-fourth pounds shredded wheat | 2125 | |
| One pound uncooked macaroni | 1665 | |
| One and one-third pounds white wheat bread | 1520 | |
| One and one-fourth pounds crackers | 2381 | |
| One and two-thirds pounds flaked rice | 2807 | |
| Three-fifths pound dried beans | 963 | |
| One and seven-eighths pounds baked beans | 1125 | |
| One-half pound dried peas | 827 | |
| One and eleven-twelfths pounds potato chips | 5128 | |
| Two-thirds pound almonds | 2020 | |
| Two-fifths pound pine nuts, pignolias | 1138 | |
| One and two-fifths pounds peanuts | 3584 | |
| Ten pounds bananas, edible portion | 4600 | |
| Ten pounds grapes | 4500 | |
| Eleven pounds lettuce | 990 | |
| Fifteen pounds prunes | 5550 | |
| Thirty-three pounds apples | 9570 | |
* Fuel value of the quantity needed to furnish the sixty grams of proteid.
The figures in this table are instructive in many ways. First, it is to be noted that the daily proteid requirement of sixty grams can be obtained from one-half pound of lean meat (uncooked), of which the loin steak is a type. Subject to some variations in content of water, an equivalent weight of lean flesh of any variety, lamb, veal, poultry, etc., will furnish approximately the same amount of proteid. With fish, such as halibut steak, and with liver, three-quarters of a pound are required; while with sweetbreads, four-fifths of a pound are needed to furnish the requisite amount of proteid. Of salt codfish, one-half pound will provide the same amount of proteid as an equivalent weight of fresh beef; while with lean smoked bacon the amount rises to seven-eighths of a pound. Among the vegetable products, it is to be observed that dried peas and beans, almonds and pine nuts, are as rich in proteid as the above-mentioned animal foods, essentially the same weights being called for to provide the daily requirement of proteid. The same is true of cheese, the variety designated having such a composition that one-half pound is the equivalent, so far as the content of proteid is concerned, of a like amount of fresh beef. We must not be unmindful of the fact previously mentioned, however, that there are differences in digestibility among these various foodstuffs which tend to lower somewhat the availability of the vegetable products, also of the cheese, thereby necessitating a slight increase in the amount of these foods required to equal the value to the body of lean meat.
Secondly, passing to the other extreme in our list, we find indicated types of foods exceedingly poor in proteid, such as the fruits; notably, bananas, grapes, prunes, apples, etc., also lettuce, and in less degree potatoes. These are the kinds of food that may legitimately attract by their palatability, but do not add materially to our intake of proteid even when consumed in relatively large amounts. Thirdly, we see clearly indicated a radical difference between the animal foods and those of vegetable origin, in that with the former the fuel value of the quantity necessary to furnish the sixty grams of proteid is very small, as compared with a like amount of the average vegetable product. One-half pound of lean meat, for example, with its 60 grams of proteid, has a fuel value of only 308 calories, while two-thirds of a pound of almonds has a fuel value of 2020 calories, and one-half pound of dried peas 827 calories. Naturally, this is mainly a question of the proportion of fat or oil present. With fat meat, as in bacon, the calorific value rises in proportion to increase in the amount of fat, the proteid decreasing in greater or less measure.
The main point to be emphasized in this connection, however, is that a high proteid animal food, like lean meat, eggs, fish, etc., obviously cannot alone serve as an advantageous food for man. We see at once the philosophy of a mixed diet. Let us assume that our average man of 70 kilograms body-weight needs daily 2800 calories. On this assumption, if he were to depend entirely upon lean beef for his sustenance, he would require daily four and a half pounds of such meat, which amount would furnish nine times the quantity of proteid needed by his system. The same would be more or less true of other kindred animal products. On the other hand, certain vegetable foods on our list, such as flaked rice, crackers, and shredded wheat, contain proteid, with carbohydrate and fat, in such proportion that the energy requirement would be met essentially by the same quantity as served to furnish the necessary proteid. Passing to the other extreme among the vegetable products, as in potatoes and bananas, for example, we find fuel value predominating largely over proteid content. The ideal diet, however, is found in a judicious admixture of foodstuffs of both animal and vegetable origin. Wheat bread, reinforced by a little butter or fat bacon to add to its calorific value, shredded wheat with rich cream, crackers with cheese, bread and milk, eggs with bacon, meat with potatoes, etc.; the common, every-day household admixtures, provide combinations which can easily be made to accord with true physiological requirements. The same may be equally true of the more complicated dishes evolved by the high art of modern cookery.
Lastly, our table throws light upon certain questions of household economy. The cost of foods is regulated mainly not by the value of the nutrients contained therein, but by other factors of quite a different nature. Relationship between supply and demand naturally counts here as in other directions, but our demand is liable to be based not upon food values, but rather upon delicacy of flavor, palatability, and other kindred fancies, some real and some imaginary. Ordinary crackers can be purchased for ten cents a pound, but if we desire a little stronger flavor of salt and a special box to hold them, we pay eighteen cents a pound. Rolled very thin and thus made more delicate, they cost twenty-five cents, while sold under a special name and perhaps tied with a blue ribbon they cost thirty-five cents a pound. Their nutritive value per pound is the same in all cases, but we pay something for the increased labor of preparation and a good deal for the added attractiveness to eye and palate. We pay twenty-two cents a pound for round steak, thirty-two cents for loin steak, and seventy-five cents a pound for sweetbreads, the high price of the latter being regulated by the relative scarcity of the article and not by its food value. As our table indicates, the real value of sweetbread as a source of proteid is only a little more than half that of lean beef. Its fuel value, however, is somewhat more than that of beef, but a little fat added to the latter will more than compensate and at a trifling cost. When we can afford it, we pay the increased price for sweetbreads simply because their delicacy and flavor are attractive to us. We should not do it under the mistaken idea that we are indulging in a highly nutritive article of food, for as a matter of fact it is not only less nutritive than a corresponding weight of lean beef, but in addition it possesses certain qualities, in its high purin-content, that are a menace to good health if indulged in too freely.
Where expense must be carefully guarded, or where the condition of the family purse is such that conflicting demands must be intelligently considered in order to insure wise expenditure and the greatest permanent good of the many, it is well to remember that price is no guarantee whatever of real nutritive value. Two quarts of milk will furnish half the daily fuel requirement of our average man and the entire proteid requirement, while its cost is only sixteen cents. Reinforced by a pound loaf of wheat bread, the energy requirement for the day would be fully met, with surplus nitrogen to store up for future needs, and at an additional cost of only ten cents. A mixture in this proportion, however, would not be strictly physiological, since it is wasteful of proteid, but it may serve to illustrate the point. A better illustration is found in an admixture, quite adequate to supply the daily needs of our average man, both for proteid and energy, composed of one-quarter of a pound of lean beef, two-thirds of a pound of bread, and half a pound of butter, and at a total cost not to exceed thirty cents. The contrast of such prices with what is so commonly paid for table delicacies is somewhat striking; it could be made still more so by drawing upon many common vegetable foods, rich alike in proteid and in fuel value, the cost of which is even less than the simple food mixtures just referred to. It is not necessary, however, to enlarge upon this question; it is sufficient to merely emphasize the fact that the exaggerated demand of our present generation for dietetic luxuries is leading us far away from the proverbially simple life of our forefathers, and without adding in any way to the effectiveness of the daily diet. On the contrary, it is in part responsible for the high proteid consumption of the present day, with its attendant evils, and involves a large and unnecessary expenditure without adequate return. The wants of the body for food are far more advantageously met by a simple dietary, moderate in amount and at an expense comparatively slight.
A recent writer,[76] in the “British Medical Journal,” a practitioner of medicine in the Highlands of Scotland, has said that these are “facts of common experience in the Highlands of Scotland, and probably among the peasantry of other countries also, where the old beliefs and customs have not too readily given way to the luxuries of civilization. Oatmeal in one form or another is a daily ingredient in the diet of a Highland peasant. The potato also is a staple food, and is consumed in large quantities with salt herring or other fish, and perhaps in some cases salt mutton or pork. Milk and eggs are used by most. The growing consumption of tea, however, and the increasing relish for sweets, candy, pastry, and biscuits, threaten to destroy the old way of living. A typical day’s diet for a crofter or fisherman who still believes in the traditional diet would be somewhat like this:
Breakfast.—Oatmeal porridge or brose with milk; bread, butter, and tea.