As we have already seen, nitrogen in the form of protein is necessary to the life of every cell in the body. From protein, too, muscle is built, though we cannot build good muscle merely by feeding protein; a diet moderate in its amount of protein, but with plenty of fuel for healthy exercise is best for muscle building. Under all ordinary conditions, if ten to fifteen Calories in every hundred (10 to 15 per cent of the total Calories) are from protein, the need for this kind of building material will be met. Thus a family requiring 10,000 Calories per day should have from 1000 to 1500 of these as protein Calories. The following table gives the protein Calories in the 100-Calorie portions of some common food materials.
TABLE SHOWING DISTRIBUTION OF CALORIES IN 100-CALORIE PORTIONS OF COMMON FOOD MATERIALS
====================+======+========================== | | DISTRIBUTION OF CALORIES | | FOOD MATERIAL |WEIGHT|-------+-----+------------ | |PROTEIN| FAT |CARBOHYDRATE --------------------+------+-------+-----+------------ |Ounces| | | | | | | Almonds, sh.e.l.led | 0.5 | 13 | 77 | 10 | | | | Apples, fresh | 7.5 | 2 | 6 | 92 | | | | Bacon | 0.5 | 6 | 94 | -- | | | | Bananas | 5.5 | 5 | 6 | 89 | | | | Beans, dried | 1.0 | 26 | 5 | 69 | | | | Beef, lean round | 2.5 | 54 | 46 | -- | | | | Bread | 1.4 | 14 | 4 | 82 | | | | b.u.t.ter | 0.5 | 1 | 99 | -- | | | | Cabbage | 13.3 | 21 | 7 | 72 | | | | Carrots | 10.1 | 10 | 5 | 85 | | | | Cheese, American | 0.8 | 27 | 73 | -- | | | | Cod, salt (boneless)| 3.1 | 98 | 2 | -- | | | | Cornmeal | 1.0 | 10 | 5 | 85 | | | | Eggs, whole | 2.7 | 36 | 64 | -- | | | | Flour, white | 1.0 | 12 | 3 | 85 | | | | Lamb chops | 1.3 | 23 | 77 | -- | | | | Lentils | 1.0 | 29 | 4 | 67 | | | | Macaroni | 1.0 | 15 | 2 | 83 | | | | Milk, whole | 5.1 | 19 | 52 | 29 | | | | Milk, skimmed | 9.6 | 37 | 7 | 56 | | | | Oats, rolled | 0.9 | 17 | 16 | 67 | | | | Peanuts, sh.e.l.led | 0.6 | 19 | 63 | 18 | | | | Peas, canned | 6.4 | 26 | 3 | 71 | | | | Peas, dried | 1.0 | 27 | 3 | 70 | | | | Salmon, canned | 2.4 | 54 | 46 | -- | | | | Veal | 3.2 | 70 | 30 | -- | | | | Walnuts, sh.e.l.led | 0.5 | 10 | 82 | 8
Notice that some foods, like bread, have about the right proportion of protein calories; others, like beef, beans, and peas are very high in protein calories. By combining some foods high in protein with others containing little or none, we can get the right proportion. Thus, 100 Calories of beef combined with 400 each of bread and b.u.t.ter will give 900 Calories of which 114, or 12.7 per cent, are from protein.
========================================================= | PROTEIN | TOTAL | CALORIES | CALORIES ----------------------------------+-----------+---------- Beef | 54 | 100 Bread | 56 | 400 b.u.t.ter | 4 | 400 ----------------------------------+-----------+---------- Totals | 114 | 900 ========================================================= (114 900 = 0.127 or 12.7%)
It is interesting to work out other combinations which give these good proportions.
=Ash requirement.=--We are also a.s.sured of ash in any ordinary diet, but some attention should be paid to kind and amount, especially as many common foods have lost the parts richest in ash. Patent flour, for instance, made from the inner part of the grain, is not so rich in ash as whole or cracked wheat. Valuable salts are also lost in cooking vegetables when the water in which they were cooked is thrown away. If not desired with the vegetable, this should be saved for gravy or soup. It is not necessary to calculate a definite amount of ash for the diet, if ash-bearing foods are freely used. By reference to the table on page 384 you can see what foods are valuable for supplying the important kinds of ash. Milk is particularly rich in calcium and hence is required when the bones are growing. Eggs have iron and phosphorus in forms well suited to growth. But if eggs are too expensive, the vegetables and fruits generally will supply these same substances.
=Diet for growth.=--Diets made in the chemical laboratory from mixtures of pure (isolated) protein, fat, carbohydrate, and ash to satisfy all the requirements which we have so far mentioned, do not behave alike when fed to animals. The kind of protein is important as well as the amount. This is shown by experiments in which only one protein is fed at a time. On some, the animals will not thrive. On others, adult animals do very well, but the young ones become stunted like the one shown on page 295. Milk has been found to contain proteins on which young animals can thrive. But even in diets containing the protein from milk, young animals do not develop normally unless the salts of milk are added too. No perfect subst.i.tute for milk has ever been found. During the first year of life, a child lives on it almost exclusively; for the first five years it should be considered the most important article in the diet; and throughout the period of growth it should be freely used if children are to become vigorous men and women. If not liked as a beverage, it can be used in cocoa, or cereal coffee, in soups, puddings, and other dishes. Considering what milk may save in the way of more expensive protein foods, such as eggs and meat, and of ash-supplying foods like fruits and vegetables, it is to be regarded as a cheap food. It is possible to get the proper amounts of fuel and protein from white bread and meat, but such a diet is poorly balanced as to ash const.i.tuents and especially lacks calcium. It would need to be balanced by adding some fruit or vegetable and even then would not contain as much calcium as is best for growing people. A diet of bread and milk, on the other hand, is so nearly perfectly balanced (supplying fuel, protein, and ash const.i.tuents in suitable amounts) that it can be taken exclusively for a long time. Whole wheat bread and milk would be even better, because the whole wheat would supply more iron, in which white bread and milk are not rich. The addition of fruits and vegetables to the bread and milk diet would also be an advantage--partly for the same reason.
Other foods especially valuable for growth are eggs and cereals from whole grains. Children should acquire the habit of eating fruits and green vegetables of all kinds, for when they are older and likely to take less milk and cereals, the fruits and vegetables supply important ash const.i.tuents and also help to prevent constipation.
The foods good for children are also good for adults, but the latter can keep their bodies in good repair with less protein and ash in proportion to body weight than are required during growth, and many kinds of protein serve for repair. If there are not enough milk and eggs to go around, adults can take meat, nuts, peas, beans and bread for protein, and trust to these and fruit and vegetables for ash. When the body has been wasted by sickness, however, a return to the foods of growth, especially a diet of milk and eggs, is best for building it up again.
=The number of meals in a day.=--Knowing how much and what kinds of food are best for each member of the family, we must next find out how to divide the total food for the day into meals. Few of us could take our required fuel in one meal, and if we could, we should probably be hungry before the time for the next meal. Some persons get along very well with two meals a day, but usually their fuel requirement is not high. Most people are more comfortable and more likely to eat a suitable amount in a deliberate fashion if they have three meals a day. When large amounts of fuel have to be taken, four or five meals may be better than three; babies who have to eat in proportion to their size, often 2-1/2 times as much as their mothers, take 2-1/2 times as many meals, _i.e._ 7 or 8 in a day.
=The amount of food for each meal.=--While the number of meals depends largely on the amount to be eaten in the whole day, and the appet.i.te of the subject, the amount at each meal is most influenced by the nature of the daily occupation. The baby with nothing to do but eat and sleep has meals uniform in kind and amount. The business man who works very hard through the middle of the day, and has not time to take an elaborate meal, nor time to rest after it so that it may digest easily, takes a light luncheon and makes up for it at breakfast and dinner. The outdoor worker who has a long hard day and expends much energy, takes an hour at noon for a substantial dinner, in addition to a hearty breakfast and supper and sometimes a mid-forenoon or mid-afternoon lunch.
=Regularity of meals.=--More important than the number of meals is regularity as to time of eating and amount of food. Training for the digestive tract is just as important as training the eye or the hand or the brain. We cannot expect good digestions if we have a hearty luncheon to-day, none at all to-morrow, and perhaps a scanty and hasty late one the next day. To take food into the stomach between meals is to demoralize the digestive system. Foods that are excellent as part of a meal provoke headaches and bad complexions, and many symptoms of a protesting stomach, when taken between meals. The younger the person, the more important is regularity. Little children soon suffer if their meals are not "on the minute." Adults have more difficulty in controlling their time, but if they have to be late to meals, they should be more careful than usual to eat slowly and to choose plain simple food that will digest easily.
=Mental att.i.tude toward meals.=--Good food may be provided at the proper time and yet the members of a family may fail to keep well and happy unless they come to meals in the right condition. Haste, chill, exhaustion, anxiety, excitement, fretfulness, or anger may interfere with the digestion of the most digestible of meals. Orderly table service, good manners, and cheerful conversation are very important factors in the success of a meal. Peace and joy as well as "calories" are watchwords of good nutrition.
=Balanced meals.=--Having determined how many meals to serve in the day and what their hours shall be, the next question is how to choose and distribute the const.i.tuents of the day"s ration so as to promote digestibility and satisfaction. A meal of pure protein, or fat, or carbohydrate would not be relished, and would have some physiological disadvantages. Digestion is likely to be more complete on a mixed diet. A meal of carbohydrate alone leaves the stomach more quickly than any other kind, and one would feel hungry before the next meal, though one might have had plenty of fuel; a meal of fat alone would leave the stomach very slowly, and one would not have so good an appet.i.te for the next meal; a meal of pure protein would stimulate heat production without any particular advantages, except possibly in very cold weather: it would be decidedly undesirable in hot weather. For these and other reasons it is best to have the different foodstuffs represented in each meal, and to see that no one contains an excess of fat, which tends to r.e.t.a.r.d all digestion. This is what is usually meant by a balanced meal, but it may also include care that about the same proportion of fuel is served at the same meal each day. A meal does not need to be "balanced" in quite the same sense as a day"s ration. The latter must have a definite amount of fuel, a suitable proportion of protein, ash well represented, some food for bulk, the whole selected with regard for the physical condition, tastes, habits, and pocketbooks of those to be fed.
=Menus.=--Food taken at a stated time const.i.tutes a meal. It may consist of a single food material, as bread, or a single dish, as soup; or it may contain many kinds of food and many dishes. When the day"s ration consists of a single food, there is no trouble in arranging the bill of fare, for all meals are alike. But as soon as we have two foods, we may consider whether they will digest better if eaten together or separately, and which way they will please the palate better. Balanced diets do not necessarily afford attractive menus. Macaroni and oatmeal would make a fairly well balanced meal except as regards ash const.i.tuents, but no one would call such a combination pleasing. By the subst.i.tution of a little cheese and an orange for the oatmeal, a meal containing about the same fuel value and proportion of protein could be arranged, and it would certainly appeal more to the appet.i.te, and furnish better proportions of ash const.i.tuents.
In the construction of the menu for the day or meal, we must consider not only food values and time of day and combinations which shall be digestible, but flavor, color, texture, and temperature of our foods. The study of digestible combinations belongs to the science of nutrition. The harmonious blending of tastes, odors, colors, and the like is an art. Just as there are pleasing combinations of sound, so there are harmonies of flavor; certain dishes seem naturally to "go together." Habit has a great deal to do with food combinations. A Chinaman would not eat sugar on rice; a j.a.panese would not cook beans with mola.s.ses as the Bostonian does. It is interesting to experiment with new combinations, and study to find out why old ones are pleasing. Why do we like crackers with soup? b.u.t.ter on bread?
Toast with eggs? Peas with lamb chops?
=Digestible menus.=--Some of our eating habits are worth preserving and cultivating. Fresh fruit for breakfast stimulates the appet.i.te and helps to prevent or overcome constipation. A mild-flavored food like cereal is better relished before we have had meats or other highly flavored food.
Soup at the beginning of a meal puts the stomach in better condition to digest the food that follows. Ice cream at the end of a meal is less likely to chill the stomach than at the beginning. Bread and b.u.t.ter afford a good combination of fat and carbohydrate. Crackers help in the breaking up of cheese into particles easy to digest.
Not all of our eating habits are good, however. Griddlecakes, melted b.u.t.ter, and maple sirup taste good, but the cakes make a pasty ma.s.s difficult for digestive juices to penetrate. The sirup is likely to ferment, and the b.u.t.ter coating the whole delays digestion greatly.
Chicken salad is popular, but combinations of protein with much fat (as in the mayonnaise dressing) always digest very slowly. Simple dishes, without rich sauces or gravies, and not excessively high in fat, are easiest of digestion. Pastries, fried foods, meats with much fat, like pork and sausage, are always more or less difficult and should be attempted only by the strong, or when the body is free from physical or nervous weariness, and not about to undertake mental work.
Attention to the art of menu making not only helps to make the diet easier to digest, but also better balanced. Foods which are similar in color, flavor, and texture, like potatoes and rice, are not artistic in combination, and it is better to subst.i.tute for one of them a green vegetable, or meat or b.u.t.ter, in which case we get a better balance, as more ash, protein, or fat would then be included with the starch of the rice or potato.
In making the bill of fare it is a great mistake to consider each meal by itself alone. If we do so, some days are likely to be very high in fuel, while others may be very low. Then, too, the impression left from one meal carries over to the next. We do not care to see on the dinner table the same foods that we saw at luncheon. Our love of variety is one of nature"s ways of seeing to it that we get different kinds of foodstuffs in our diet. Variety stimulates appet.i.te, but this does not mean a great variety at one meal. The truest variety is obtained by a few well-selected dishes at each meal. If we do not exhaust our resources on one meal, we shall be able to have a greater range of foods in the course of a week. A hotel may have fifty or sixty items on its bill of fare, but after a few days one feels as if there were a great sameness, because all of them are impressed on the mind at each meal and every day.
=Dietaries.=--A dietary, as we shall use the term here,[19] is a statement of the food requirements of a person or group of persons for a day or some other definite length of time, with a selection of foods to satisfy this requirement.
The first part of a family dietary will have to be calculated according to the age, weight, and occupation, as stated on pages 299-303. When complete, it will stand somewhat like this:
FOOD REQUIREMENTS
------------------+------------+-----------+-------------+------------- MEMBERS OF FAMILY | AGE | WEIGHT | TOTAL | PROTEIN | | POUNDS | CALORIES | CALORIES ------------------+------------+-----------+-------------+------------- Man | 40 | 154 | 2680 | 268-402 Woman | 38 | 120 | 2160 | 216-324 Girl | 16 | 110 | 2200 | 220-330 Boy | 12 | 75 | 2250 | 225-338 Boy | 6 | 40 | 1600 | 160-240 ------------------+------------+-----------+-------------+------------- Total requirements | 10,890 | 1089-1634 ------------------+------------+-----------+-------------+-------------
In selecting food to satisfy these requirements it is a good plan to make first a list of those foods that need to be included in the day"s dietary, no matter what the particular menu may be. This will include foods for growth where there are children, special dishes needed if any one is sick, and those common foods which we are accustomed to include in every day"s menu, such as bread and b.u.t.ter.
For the family which we are considering, this list will stand somewhat as follows:
FOOD 100-CALORIE PORTIONS Milk 20[20] (6 for each child, the rest for the Cereal 5 adults) Eggs (for children) 2 (counting 2/3 portion per egg) Fruit 5 Green vegetable 2 Meat or meat subst.i.tute 5 Bread 15 b.u.t.ter 15
This list is to be kept in planning the menu, whose character is further determined by certain dishes which we wish particularly to have included.
For instance, we may desire roast beef for dinner. This is a highly flavored meat, and a protein food which will go a long way towards satisfying the adult"s protein needs. Special protein food for breakfast may well be omitted, or take the form of eggs, which are a contrast to the meat in flavor, form, etc. Protein food for luncheon might be fish or some other meat subst.i.tute.
Vegetables for dinner should not only harmonize with the meat, but contrast pleasingly with each other. This result is insured by choosing one vegetable from the starchy type, as potatoes or sweet potatoes, and the other vegetable of the green or succulent group, as spinach or asparagus.
Below are two menus, in which have been kept in mind the foods which ought to be included (see page 311) and the artistic arrangement of the day"s meals, with roast beef as the keynote.
Menu No. I. Menu No. II.
_Breakfast_ _Breakfast_
Oranges Grapes
Flaked wheat Oatmeal
Twice baked rolls and Toast with b.u.t.ter b.u.t.ter Cereal cafe au lait for Milk for children children
Coffee for adults Coffee for adults
_Luncheon_ _Luncheon_
Creamed salmon on toast Eggs au gratin
Peas Stewed tomatoes
Graham bread and b.u.t.ter Bread and b.u.t.ter
Stewed pears Raspberry tapioca
Milk to drink Cocoa
_Dinner_ _Dinner_
Clear tomato soup Julienne soup
Roast beef Roast beef
Mashed potatoes, string Creamed macaroni, beans spinach
Cabbage salad Celery and nut salad