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FOODS WE EAT
Put this puzzle together and you will find milk, cheese and eggs, meat, fish, beans and cereals, greens, fruits and root vegetables -- foods that contain our essential daily needs.
Exactly how they interlock and in what quantities for the most advantageous results for every one of us is another puzzle we must try to solve for ourselves, keeping in mind our age, body type, activities, the climate in which we live, and the food sources available to us. How we wish someone could present us with hard and fast rules as to how and in what exact quantities to assemble the proteins, fats and carbohydrates as well as the small but no less important enzyme and hormone systems, the vitamins, and the trace minerals these basic foods contain so as best to build body structure, maintain it, and give us an energetic zest for living!
Where to turn? Not to the sensational press releases that follow the discovery of fascinating bits and pieces about human nutrition; nor to the oversimplified and frequently ill-founded dicta of food faddists that can lure us into downright harm. First we must search for the widest variety of the best grown unsprayed foods we can find in their freshest condition, and then look for foods with minimal but safe processing and preservatives and without synthetic additives. While great strides have been made in the storage of foods commercially and in the home, if fresh foods in good condition are available to you, choose them every time. To compare the nutritive values in frozen, canned and fresh vegetables, see 798.
Next we can find in the U.S. Handbook on the Composition of Foods some of the known calorie, protein and other values based on the edible portions of common foods. Recent mandatory labeling information, 7, is of some help, although the U.S. Recommended Daily Allowances are based on information from a nongovernmental agency, the National Research Council, a source not acceptable to some authorities. But no one chart of group of charts is the definitive answer for most of us, who are simply not equipped to evaluate the complex relationships of these elements, or to adapt them to the practicalities of daily living. Such studies are built up as averages, and thus have greater value in presenting an overall picture than in solving our individual nutrition problems.
Nevertheless, by applying plain common sense to available mass data, we as well as the experts are inclined to agree that many Americans are privileged to enjoy superabundance and that our nutritional difficulties have to do generally not with under- but with overeating. Statistics on consumption also bear out other trends: first, that we frequently make poor choices and eat too much of the wrong kinds of foods; second, that many of us overconsume drugs as well as foods. Medication, often a lifesaver, may, when used habitually, induce ah adverse effect on the body's ability to profit fully from even the best dietary intake.
Individually computerized diagnoses of our lacks may prove a help in adjusting our deficiencies to our needs. But what we all have in our bodies is one of the greatest of marvels: an already computerized but infinitely more complex built-in system that balances and allocates with infallible and almost instant decision what we ingest, sending each substance on its proper course to make the most of what we give it. And since nutrition is concerned not only with food as such but with the substances that food contains, once these essential nutrients ate chosen, their presentation in the very best state for the body's absorption is the cook's first and foremost job. Often taste, flavor and color at their best reflect this job well done. Read The Foods We Heat, 145, and follow our pointers to success for effective ways to preserve essential nutrients during cooking. And note at the point of use recommendations for optimum storage and handling conditions, for one must always bear in mind the fragility of foods and the many ways contaminants can affect them, and consequently us, when they are carelessly handled or even when such a simple precaution as washing the hands before preparing foods is neglected.
But now let's turn to a more detailed view of nutritional terms: calories, proteins, fats, carbohydrates, accessory factors like vitamins, minerals, enzymatic and hormonal fractions -- all of which are needed -- and see how they interact to maintain the dietary intake best suited to our individual needs.
A too naïve theory used to prevail for explaining regeneration through food. The human system was thought of as an engine, and you kept it stoked with foods to produce energy. Food can be and still is measured in units of heat, or calories. A Calorie, sometimes called a kilocalorie or K Calorie, is the amount of heat needed to raise one kilogram of water one degree Centigrade. Thus translated into food values, each gram of protein in egg, milk, meat or fish is worth four calories; each gram of carbohydrate in starches and sugars or in vegetables, four calories; and each gram of fat in butters, in vegetable oils and drippings, and in hidden fats, 5, about nine calories. The mere stoking of the body's engine with energy-producing foods may keep life going in emergencies. But to maintain health, food must also have, besides its energy values, the proper proportions of biologic values. Proteins, vitamins, enzymes, hormones, minerals and their regulatory functions are still too complicated to be fully understood. But fortunately for us the body is able to respond to them intuitively.
What we really possess, then, we repeat, is not justa simple stoking mechanism, but a computer system far more elaborate and knowledgeable than anything that man has been able to devise. Our job is to help it along as much as possible, neither stinting ir nor overloading it. Depending on age, weight and activity the following is a rough guide to the favorable division of daily caloric intake: a minimum of 15% for proteins, under 25% for fats, and about 60% for carbohydrates. These percentages are relative: some people with highly efficient absorption and superior metabolism require both lower intake and the lesser amount of protein. No advice for reducing is given here, nor are the vaunted advantages of unusually high protein intake considered -- as again such decisions must be highly individual, see About Proteins, at right. In general, and depending also on age, sex, body type and amount of physical activity, adults can use 1700 to 3000 calories a day. Adolescent boys and very active men under fifty-five can utilize close to 3000 calories a day. At the other extreme, women over fifty-five need only about 1700 calories. Women from eighteen to thirty-five need about 2000 calories daily. During pregnancy they can add 200 calories and, during lactation, an extra 1000 calories. Children one to six need from 1100 to 1600. Before a baby's first birthday, his diet should be closely watched, and parents should ask their pediatricians about both the kinds and the amounts of food to give their baby.
Given your present weight, perhaps a more accurate way to calculate your individual calorie requirement is to consider your activity rate. If you use a car to go to work and have a fairly sedentary job, or even if you are a housewife with small children, your rate is probably only 20%; 30% if you are a delivery man of patrolman working out of doors, and 50% if you are a dirt farmer, construction worker or athlete in training. If you multiply your weight by 14 calories, you will get your basal need, that is, the calories you would require if you were completely inactive. When you multiply this amount by your own activity factor and add it to your basal needs, you should get ah approximation of your required daily caloric intake. If you reduce your caloric intake much below this approximate norm, you may be lacking in your mineral, vitamin and protein requirements. Whatever your caloric intake, distribute your choices properly among protein, fat and carbohydrate values.
On our protein intake depends the constant virtual replacement of self. And nowhere in the diet is the relation of quantity to quality greater. The chief components of proteins are 22 amino acids. They form an all-or-nothing team, for food is utilized by the body only in proportion to the presence of the scarcest of them. Fourteen of the 22 aminos are both abundant and versatile. If they are not present when food is ingested, the body is able to synthesize the missing ones from those present. The remaining 8 aminos, however, cannot be synthesized and must be present in the food when ingested. These eight are known as the essential aminos. Four of them -- leucine, valine, phenylalanine and threonine -- are relatively abundant in foods, but the other four -- isoleucine, lysine, methionine and tryptophan -- are more scarce. And because utilization of protein by the body depends in each instance on the least abundant member of the essential aminos, these latter four are known as the key aminos.
Generally speaking, proteins from animal sources like egg? meat, fish, and dairy products are valued because their total protein content is high, and they are referred to as complete because they are rich in the essential aminos, and therefore more of the total protein present is utilizable. Those from vegetable sources such as whole grains, nuts, seeds, and legumes -- with the exception of soybeans -- are less valuable because their total protein content is low. They are referred to as incomplete because they are also Iow in one or more of the eight essential amino acids, meaning that less of their total protein can be utilized by the body. The terms "complete" and "incomplete" ate somewhat misleading, however, because of their absolute connotations. It is still possible to fulfill your daily requirements for protein from incomplete vegetable sources, provided you are willing and able to consume large enough quantities of the incomplete protein item in question. But the utilizable protein content of most cereals is so poor that consuming enough to satisfy protein requirements would be a practical impossibility.
Take corn, for example. It has little protein and many starch calories. A diet based exclusively on corn would require consumption of enormous quantities of com to establish the needed essential aminos. A complete protein source like eggs would therefore be more realistic and desirable in satisfying the same protein requirement with far less caloric intake. In fact, for 10 grams of egg protein at 125 calories, you would have to eat 16.5 grams of corn protein at 500 calories to get ah equivalent amount of usable protein. But since no one wants to live on corn or eggs alone, a more reasonable way to approach the problem is to note how complete and incomplete proteins complement each other.
There are various ways of expressing protein values -- net protein utilization, of NPU; protein efficiency ratio, of PFR; and biologic value, or BV. Another unit of measure used on product labels is protein value in relation to casein, 7. Although these terms are all derived by different methods, they correlate well with each other. Whatever the method of expressing this utilization efficiency, one fact remains: that is, the body requires certain kinds and amounts of essential amino acids which must be supplied each day.
Any excess intake of amino acids not compensated for is metabolized away and thus not used for growth or maintenance of the body. Eggs, with a BV of 94, may be considered the most ideal protein from the point of view of utilization to replace body protein. But we can't survive on one food alone.
If we combine durum wheat, with a BV of 60, and lima beans, with a BV of 50, we get through their complementarity of utilizable protein a score of 60. But a BV of 60 is marginal for body replacement, and so a more complete protein such as that contained in milk of eggs should be added to such a meal. Combine, for instance, I tablespoon of peanut butter, with a BV of 43, and one slice of white bread, with a BV of 52. If you add 4 ounces of milk, with a BV of 86, the combination stabilizes at a BV of approximately 80.
In countries dependent mainly on beans and rice of other cereal combinations, the beneficial effects of adding to the diet even small amounts of meat, fish, eggs or dairy products is well recognized. And when various pastas are the staple foods, the inclusion of at least one-third in the form of a complete protein is considered the minimal amount to bring the meal up to acceptable levels. Furthermore, it should be stressed that any meal of snack which fails to include sufficient complete protein, although it may temporarily stay one's hunger, will not replenish all of the metabolic Iosses of the body.
In regions where only vegetable protein is available, grains combined with pulses such as beans and peas ate classic. It has been found that increments of about one-third complete protein reinforce incomplete protein to form a total that is greater than the sum of its parts.
Even more significant differences ate found between processed and unprocessed foods. Brown rice has a BV of 75, as opposed to white rice with a BV of 65. Whole wheat bread has a BV of 67; white bread, 52.
To meet the needs of underdeveloped areas and the threat of worldwide protein shortages, in recent years experiments involving grain, seed and legume combinations, 198, have been undertaken which may one day prove valuable to all of us. Gross nutritional deficiencies ate more conspicuous in areas where protein imbalances are drastic and prolonged, and the effects of improved diet are easier to evaluate than in areas like ours, where such deficiencies are less severe and thus harder to detect. Until recently, we have relied on animal experimentation, and although dietary results thus achieved are valuable, they are not always applicable to man, and, for the most reliable results, data must be based on human reactions.
Since vegetable proteins are incomplete except as noted above, ir is wise to draw two-thirds of the daily protein intake of 10% of your caloric intake from animal sources. Preferably, meats should be fresh -- not pickled, salted or highly processed. Protein foods when cooked should not be subjected to too high heat, for then they lose some of their nutrients. Familiar clanger signals are curdling in milk, "stringiness" in cheese and dryness in meat and fish.
Protein requirements generally are slightly higher in colder climates but no matter what the climate, growing children, pregnant women and nursing mothers need a larger proportion of protein than the average adult. The elderly, whose total caloric intake often declines with age, should consume a relatively larger percentage of protein to reinforce their body's less efficient protein metabolism. Again, absolute amounts cannot be given, because needs will depend on the efficiency of utilization by your own body. If your protein supply is largely from meats, fish, fowl and dairy products, a useful formula for calculating average daily protein intake is to allow 4 gram of protein per pound of body weight for adults, and for children from one to three years, 1 gram of protein per pound of body weight. In vegetarian diets structured on vegetable sources alone, with no animal by-products such as eggs and milk, careful balancing is needed to ensure enough complete protein. It is also suggested that the protein content of such a diet be upped from 4 to 5 gram per pound of body weight.
Experiments have shown variations in protein utilization between individuals to be as high as two to one. They have also demonstrated that an individual's protein needs may rise by one-third when he is under great physical of emotional stress. A natural luster in hair, firmness of nails, brightness of eyes and speed of healing are superficial indications of a well-being that comes from adequate protein intake. For a listing of approximate protein content -- complete, incomplete and mixed -- in average servings of individual foods, see 8.
Today, we cannot mention protein and protein sources without looking beyond our own frontiers. With overpopulation a world problem, can we continue our upward trend in meat consumption? Amounts of land required to produce protein increase by a ratio of one to ten as we proceed from the beginning to the end of the food chain: that is, from the growing plant to meat-eating man. To put it another way, the herbivorous animal must consume about 10 pounds of vegetable or cereal matter to turn it into 1 pound of meat. Or, as another example, the same amount of land is required to produce 10 pounds of soybeans as 1 pound of beef. You can readily see that there is protein waste in this type of food production.
As long as chickens scratched more or less on their own; as long as pigs scavenged family wastes; as long as cattle, ingested grasses from lands often too rough or too dry for efficient grain harvesting, a something-for-nothing process existed. Today's animal husbandry competes in the main for crops that could also be utilized by humans. Chickens fed in batteries, pigs and cattle concentrated in feed lots need preprocessed foods and drugs to prevent the diseases these abnormal living conditions encourage. And their droppings, once recycled on the land, are too often uselessly burned or channeled into our streams, thus initiating gross pollution of air and water.
But should conditions be changed to allot greater quantities of grains, seeds and pulses to human consumption, we would still be faced with the problem of incomplete vegetable protein. As the growing of soybeans, the only complete-protein plant, is limited to certain climates, other vegetable protein sources must be improved or compensated for by combinations of grains and pulses or by the addition of some complete animal protein.
However, amazing genetic advances have been made in the development of grain hybrids, 548, higher both in protein content and in yield than the older types: short, sturdy, storm-resistant, heavy-headed wheat and rice hybrids, rich in protein and quick-maturing; high-lysine corns; and the intergeneric rye-and-wheat hybrid, triticale, are among the recent developments that promise primary improvements in natural sources of vegetable protein. Vegetable protein mixtures, see 3, combined with dry milk or fish meals, now mainly used for animal feeding, would find greater human acceptance if they were made more palatable, which in turn would guarantee a tremendous advance in protein availability at Iow cost for all. Protein has also been developed from yeasts, algae, kelp and petroleum products, and there is even the possibility of recycling the proteins in animal wastes; but, again, unpalatability has kept most of these newer protein sources from the table.
It is of the utmost importance that we guard our ecological soundness with all the knowledge we have at hand -- knowledge that in some fields is far in advance of our willingness to apply it. It is essential that we consider new methods of utilizing and conserving land, for many of our soils ate exploited to the point of depletion and are yielding crops with reduced protein and mineral content. Other soils produce only when saturated with chemical fertilizers and develop an inability to recover crop yields without revitalization through either animal of green manuring.
We must also be on the alert for various air pollutants. Spinach and romaine, for instance, will not grow where the air-sulfur content is high, and acreage yields of grains and other vegetables in such areas are adversely affected as well. Further research is needed to explain why saltwater fish die in waters made up from our formula for seawater but will thrive in natural seawater. Readings of chromatograms of synthetic as opposed to natural vitamins reveal startling differences which ate as yet unexplained. These instances would indicate there ate present in natural substances certain micronutrients -- as yet not completely identified -- which an organism needs in order to carry on vital internal chemical processes and which are lacking in engineered of synthetically produced foods, 535.
Further research and development of genetic seedbanks, now in their infancy, ate needed to maintain efficient seed strains as the wild areas where natural hybridization has taken place are impinged on. For many of our best strains still come from fortuitous rather than man-induced selection. There is an unfortunate tendency to utilize these new seed strains in all areas before their climatic and soil adaptability has been proved, procedures that make them vulnerable to massive failure.
Again, just as variety in the selection of the foods we eat is necessary for our health, a variety of seed sources is essential to maintain the health of our foods. The breeding of plants resistant to disease, drought and insects, and tolerant of varying climates, is as important as hybridization aimed at protein increase. We like to keep in mind the wise old Indian who, when asked why he continued to grow three strains of com when only one was his favorite for food, yield and flavor, answered that he was hedging bis bets; the other two strains would always protect him against a too dry or too cold season of against insect infestation, while his favorite would succumb unless conditions were ideal.
We cannot leave our ecological musings without stressing the importance of these fundamental interrelationships, as complex and subtle in the world of edible plants as are those of the protein combinations and their subsequent utilization by the body, as discussed at left.
Although most grains are wind-pollinated, few of us realize how large and often unexpected a role insect life plays in pollination, and how insecticides can destroy this vital link in the food chain. The current abundance of fruit and vegetables in America can be traced in large part to the importation of the honeybee. The Indians had ah excess of arable land, but for many of their crops they had to rely on much less efficient native pollinators such as noncolonizing bees, wasps and flies. Today, guarding against losing helpful insects is as important as destroying insect enemies -- a fact stressed less often than is the need to solve the equally knotty problem of pesticide poisons in the food chain. We can no longer afford to ignore the interrelationships on which global food supplies depend.
While fats have acquired a bad image of late, we must not forget how essential they are. As part of our body fabric they act as fuel and insulation against cold, as cushioning for the internal organs, and as lubricants. Without fats there would be no way to utilize fat-soluble vitamins. Furthermore, the fats we eat that are of vegetable origin contain unsaturated fatty acids which harbor necessary growth factors and help with the digestion of other fats. An important consideration in fat intake is the percentage of saturated to unsaturated fats. We hear and read much about cholesterol -- that essential constituent of all body cells. It is synthesized, and its production regulated, by the liver. Cholesterol performs a number of indispensable body functions. Up to a limit, the more of it we eat, the less the liver produces. Excess cholesterol intake, however, like other excesses, is to be avoided, since a surplus of cholesterol may have serious consequences. The fatty acids in the saturated fats, which ate derived from dairy products, animal fats, coconut oil and hydrogenated fats, 541, tend to raise the amount of cholesterol in the blood, while the fatty acids in polyunsaturated vegetable oils tend to lower cholesterol levels if taken in double proportion to saturated fats. To differentiate between these types of fat, see 539.
Few of us realize that much of the fat we consume -- like the great mass of an iceberg -- is hidden. Hamburgers and doughnuts, all-American classics, contain about one-fourth fat; chocolate, egg yolk and most cheeses about a third; bacon and peanut butter, as much as one-half. And in pecans and certain other nuts and seeds, the fat content can be almost three-fourths! These proportions ate graphically suggested below.
All fats are sensitive to high temperatures, light and air. For best nutritive values store them carefully; and when cooking with them be sure that you do not let them reach the smoking point, 541. If properly handled they have no adverse effect on normal digestion. Favorable temperatures are indicated in individual recipes. Fats are popular for the flavor they impart to other foods, and for the fact that, being slow to leave the stomach, they give a feeling of satiety.
We suggest, again, the consumption of a variety of fats from animal and vegetable sources, but remind you that fat consumption in the United States has climbed in twenty years from the recommended minimum of 20% to more than 40% today.
Carbohydrates, found largely in sugars, fruits, vegetables and cereals, are classed as starches or sugars. The sugars include monosaccharides, such as fruit sugars, 557, and honey, 558, which are sweeter than the disaccharides, such as common table sugar, and the polysaccharides, such as starch. The latter two types must be broken down into simple sugars before they are available for body use. This action is initiated by an enzyme in the saliva, which means that these complex starch carbohydrates should be carefully chewed. So dunking is not only bad manners but bad practice.
The caloric value of fruits and vegetables is frequently lower than that of cereals, while that of all concentrated sweets is higher. Children and athletes can consume larger amounts of sugars and starches with less harm than can relatively inactive people; but many of us tend to eat a greater amount of carbohydrates than we can handle. Our consumption of sweet and starchy foods, to say nothing of highly sweetened beverages, is frequently excessive. Since the 1900s U.S. sugar consumption has increased by 25% , mainly in foods commercially prepared before they come into the home, making our per capita intake of these emptu calories 103 pounds annually. The imbalance that results is acknowledged to be one of the major causes of malnutrition, for the demands excess carbohydrates make on the system may cause, among other dietary disturbances, a deficiency in its supply of the vitamin B complex. For itemized Calorie Values, see 8.
Besides those already described, there are some fifty-odd important known nutrients required by the body, including minerals, vitamins, and other accessory factors. The body can store a few of these, such as the fat-soluble vitamins A, D, E and K, but others, such as the water-soluble vitamins B complex and C, must continually be replaced. The latter occur in those fragile food constituents that ate lost through indifferent handling, excessive processing, and poor cooking. For instance, if you fail to utilize vegetable cooking waters, you ate throwing out about one-third the minerals and water-soluble vitamins of the vegetable. To retain as much of them as possible, please follow the cooking suggestions given in subsequent chapters, and see About Stocks, 520.
If you maintain an adequate intake in such a way as to achieve the complete-protein and fat and carbohydrate balance described above, and ir you choose from the following food groups, you will probably include all the necessary accessory factors. So fill your market basket first so as to assure two 3-ounce servings of complete-protein foods daily -- meat, fish, fowl of eggs. Or, if you use combinations of incomplete proteins such as cereals and legumes, seeds, peanuts or gelatin, make sure you plan for the inclusion of some complete-protein food at the same meals, see 8.
Drink daily of use in cooking 2 cups of fresh milk of reconstituted dry milk, 531, or allow enough of the following milk equivalents: for each 1/2 cup of milk allow 1 cup ice cream, 1/3 cup cottage cheese of one 1-inch cube cheddar-type cheese. Ir you are one of those persons lacking the ability to digest the lactose in milk, get your major milk requirements from cheeses, which are low in lactose.
Plan four of more daily servings of starchy foods such as baked goods, cereals of pastas, accenting whole grains. Potatoes ate sometimes included in this group.
Also include daily four or more 1/2- to 3/4-cup servings of fruits and vegetables distributed among citrus fruits or tomatoes and three or more dark green or deep yellow fruits and vegetables, including preferably one raw leafy green vegetable. Also check the constituents of each meal for the bulk found in vegetables and fruits to make sure there are more high- than low-residue foods.
Foods abundant in accessory values include: eggs, cheese, butter, whole milk, egg yolks, fish-especially herring, salmon, tuna and shellfish; beans, peas, nuts, seeds and whole grains; red meats and pork, variety meats, 499; fresh vegetables -- especially the yellow and leafy green types -- including white and sweet potatoes, brown rice and yellow com; fresh fruits and berries and their juices; tomatoes and tomato juice; cabbage, spinach and cauliflower, as well as watercress, lettuces and other salad greens, and vegetable oils, 541. Bake with whole grains and flavor with brown sugars, molasses, wheat germ and butter. Don't forget to ingest one of the important accessory values, vitamin D, which you can get through exposure to sunlight, and remember that although outdoor exercise will tone your muscles and increase your oxygen intake -- and perhaps your calorie needs -- it will not necessarily make greater demands on your store of protein, vitamins or minerals.
If you have chosen wisely from the above substances, you may not need additional vitamin supplements. We all know from practical experience and statistical evidence that a well-nourished body has greater resistance to disease than a poorly nourished one. Recent research tends to support the thesis that adequate intake of accessory factors can contribute not only to disease resistance but also to disease prevention.
Other incidentals to bear in mind are: drink 5 to 7 glasses of fluid a day, including water, and, ir you live in a region that calls for ir, use iodized salt, see About Salt, 569.
The schedule outlined above is not necessarily a costly one. It is nearly always possible to substitute cheaper but equally nutritious items from the same food groups. Vegetables of similar accessory value, for example, may be differently priced. Seasonal foods, which automatically give us menu variations, ate usually higher in food value and lower in cost. You can also profitably grow your own. Whole-grain cereals ate no more costly than highly processed ones. Fresh fruits are frequently less expensive than canned fruits, which are often loaded with sugar.
If you are willing to cut down on sugar-laden processed cereals and other sugar items, especial[y fancy baked goods, bottled drinks, and candies, a higher percentage of the diet dollar will be released for dairy products, vegetables and fruits. Do not buy more perishable foods than you can properly store. Use leftovers cold, preferably. To reheat them with minimal loss, see 281.
To sum up, our fundamental effort always must be to provide this highly versatile body of ours with those elements it needs for efficient functioning, and to provide them in such proportions as to subject the body to the least possible strain.
However, not realizing the importance of variety in the selection of foods, some people are guided by calorie values alone. For instance, with bread and potatoes, almost equal in carbohydrates, you will find that bread scores higher in protein and fat factors but potatoes are greatly superior in iron, provitamin A, vitamin C and thiamin, all valuable accessory factors. Some help in making choices is available through product labeling. If any prepared and packaged food shipped in interstate commerce makes nutritional claims as to protein, fat, carbohydrate, calor(es, vitamins, minerals or enrichment, ir must have labels declaring certain nutrient contents and giving both serving size and servings per container. The food processor has the option of declaring fatty acid and/or cholesterol content. He may also indicate the sodium content in the food. Because of differences in protein quality, two levels of protein intake are shown according to the protein efficiency ratio, 8, of case(n: foods with levels equal to or greater than casein, and foods with less than casein values. If a food has less than 20% of the PER of casein, its label cannot declare that it is a source of protein. Sometimes labels indicate the percentages of available nitrogen instead of protein. Given the nitrogen percentage, you may approximate the protein content by multiplying the nitrogen figure by six.
Well-grown minimally processed foods are usually our best sources for complete nourishment; and a well-considered choice of them should in most cases meet our dietary needs.
You will find in this book, along with the classic recipes, a number which remain interesting and palatable even though they lack some everyday ingredient such as eggs or flour. These may be used by those people who have allergies. But we do not prescribe corrective diets; we feel that such situations demand special procedures in consultation with one's physician. As to the all-too-prevalent condition of overweight, it is now generally recognized that on-and-off crash diets are dangerous, and that a reeducation in moderate and varied eating habits is the only safe and permanent solution to this problem.
We stress again that the cook who has the responsibility for supplying the family with food will do well to keep alert to advances in the field of nutrition.
Take an active part in working toward consumer protection, for more and more food processors are gaining control over the condition and content of foods as we buy them. Take an interest, too, in legislative changes affecting labeling. The FDA's original intent for foods included under "standards of identity" ensured that terms like "mayonnaise" or "ice cream" would guarantee the same basic ingredients required in the government-established recipe no matter who manufactured ir. But since the manufacturer is free to disclose or reveal as he pleases a wide variety of added ingredients, the consumer is at a loss to know just what he is buying. And there is a further, more recent loophole. While formerly the word "imitation" was required on labels for any deviations from the original substance, such as variations in taste, smell, color, texture, melting quality, of method of manufacture, today the term "imitation" may be omitted if the government considers the substitute to be nutritionally equal to the original. This so-called equality of the substitute food may be chemically induced of may be achieved by additives of enrichments. "Buyer, beware!"
But in planning menus and cooking, there are considerations other than mete percentages of intake in relation to fats, carbohydrates, proteins, minerals and vitamins. Peoples have learned over the centuries how to cope with poisonous elements that exist in some of the most basic foods. They know sprouting potatoes are heavy in glycoalkaloids; that cassava must be washed in a complicated fashion to rid it of its hydrocyanic content; that soy products must be either heated or fermented to destroy their trypsin- and urease-inhibiting factors; that cabbage, ir it plays a large part in the diet, should be cooked in quantities of water to release its goiterogenic factors even at the expense of vitamin losses, just as wild greens frequently need several blanchings and discardings of the cooking water to rid them of their toxic content, 305. But peoples have also discovered a twentyfold increase in calcium content in limewater-soaked corn for tortillas; that oatmeal, if left wet and warm overnight, will with subsequent cooking release the phytin which otherwise inhibits the body's calcium absorption from other ingested food. Recently ir has been noted that the phytins in soy depress the absorption of zinc. To ensure a control factor against these and various other food pollutants, it would be wise to vary your choice of foods.
So we come back to our puzzle. Unless and Until greater and more practical advice about food properties becomes common knowledge, each of us must choose a wide variety from the basic food groups to make us feel well and to furnish our bodies with the components they need for growth and for maintaining stamina.
APPROXIMATE CALORIE AND PROTEIN VALUES IN AVERAGE SERVINGS
"Personal size and mental sorrow have certainly no necessary proportions. A large, bulky figure has as good a right to be in deep affliction as the most graceful set of limbs in the world. But, fair or not fair, these are unbecoming conjunctions, which reason will patronize in vain -- which taste cannot tolerate -- which ridicule will seize." -- Jane Austen
We have tried, from data currently furnished by the U.S. Department of Agriculture and other authoritative sources, to give you in the first column below as accurate a calorie count as possible for the total edible portion of each serving of food as ir comes to you at the table. Our soup figures ate for canned soups diluted with the same amount of water -- or whole milk, in the case of cream soups -- unless we specify them as homemade. A cup is the standard 8-ounce measure, and a tablespoon or teaspoon is always a level one. Since we do not expect you to weigh your food at table, this chart should give you a fairly accurate guide to normal servings fora healthy adult. Remember, however, that two martinis before dinner count as much as a generous slice of pie for dessert, and, if you are watching your weight, second thoughts may be better than second helpings.
To use the protein values in the second column on the charts which follow, determine how many grams of protein you require each day, 3. Remember that adequate protein is vital for body maintenance and repairs. Note that with some foods you get too many calories per grato to make that food desirable as a protein source, 3. What is the price in calories you have to pay for a given grato of protein? To find out, divide the number of calories given in a portion of food by the grams of protein in that same portion of food. Foods with less than 35 calories per grato of protein ate considered acceptable. Those with 35 to 70 calories ate considered marginal, and those with 70 or more calories per grato are usually considered unacceptable. But it must be pointed out that the above figures apply only to protein values. While the apple, for instance, is clearly unacceptable for its protein value, it is treasured for its vitamins and minerals and its carbohydrates, mainly in the form of natural sugars. Again there must be a balancing of interrelationships in your intake of basic requirements.
In calculating protein content for the foods below, we have followed those values as suggested by government laws on labeling expressed as to whether the Protein Efficiency Ratio is greater of less than that of casein, the chief protein of milk. You will need 45 grams if the PER is equal to of greater than casein, in which case the figure is in bold-face type, and 65 grams of protein if the PER is less than the value of casein, in which case the figure is in light-face type. Ir the protein has a value of less than 20% of casein, it cannot be considered a significant source of protein and should not be included in your protein calculations. If the figure appears in italics, there is a mixture of foods. A "T" indicates only a trace of protein, and where a dash appears, reliable information on the protein value is not presently available.
Copyright © 1931, 1936, 1941, 1942, 1943, 1946, 1951, 1952, 1953, 1962, 1963, 1964, 1975, by the Bobbs-Merrill Company, Inc.