The Nutritive Value of The Less-important Foods

New Zealand Journal of Agriculture, Volume 79, Issue 3, 15 September 1949, Page 291

The Nutritive Value of The Less-important F oods

THE large number of foods commonly called “protective foods” « j. - 11 i i by dietitians contain, as well as their calorie or energy value, which all foods have to a greater or less extent, the essential nutrients vitamins, minerals, and proteinin sufficient amounts to make an important contribution to the body’s requirement of one or more of . them. The special nutrient content and therefore the importance of ,■rir > • i i < these protective foods, most of which happen to be natural or unrefined foods such as milk, vegetables, eggs, and fruit, have been discussed in two. previous articles by, Evelyn E. Moore, Rural Sociologist, Department of Agriculture, Palmerston North. This article deals with the value of foods which, generally because, of their ' poorer nutrient content, are not to be recommended as substitutes or often even nartial substitutes for the nrotertive foods onen even partial suDsututes tor me protective roods.

THESE foods may be used in addition A to the protective foods to improve flavour and provide greater variety in the menu, and some of them, especially fats, are most important contributors to the energy value of the diet, particularly of hard-working men and women and energetic adolescents, They also include beverages, which are a very important' part of the menu - from the gastronomical point of view, though sometimes of negligible value nutritionally. ' Oils and Fats Though they may appear slightly different, all oils and fats have practically the same energy content. They are particularly-good energy foods, containing slightly more than twice as many, calories as sugar, and the latest scientific evidence indicates that a combination of fats with starchy or sweet

foods is more economical of the essential vitamin B t or thiamine than starches and sugars used alone. i n addition, fish-liver oils and butter are protective foods Butter is the mos t nutritious of the common culinry f a ts and oils' containing appreciable amounts of vitamin A Fish oils are also excellent sources of vitamin a and contain vitamin D and iodine as well; in fact, they are the only foods which contain -vitamin D in sufficient amounts to meet the requirements of babies and expectant and nursing mothers, who often are not able to obtain sufficient by exposure to sunshine. As all other fats contain negligible amounts of nutrients they are of less value and should not appear too frequently in the menus of other than people doing hard manual work,-ath-letes, or energetic children and adolescents, for their very high energy value

and small bulk may lead to their consumption in excess of energy requirements by sedentary people, causing overweight. Pastries, fried foods, roasted vegetables, and other fat foods, though certainly not harmful, are most suitable for energetic people, and certainly should be eschewed by all with a tendency to be overweight. Sugars Sugar, golden syrup, honey, jam, and other sweets are all good energy foods, but otherwise are of negligible value nutritionally. In addition, the popularity of sweets and sugar is regarded by nutritional authorities and dentists as one of the important causes of the high incidence of tooth decay among New Zealanders. Different forms of sugar, such as •ordinary cane sugar (sucrose), glucose, honey, and milk sugar (lactose), .are often supposed, quite without reason, to vary in their nutritive value, honey, glucose, and milk sugar generally having the reputation of being better for health than ordinary sugar. That glucose does not require digestion is true, but as sugar is very easily digested, no advantage is gained by

substituting glucose except perhaps for children or invalids with digestive disorders. ■ ' The only foods in this group which have some slight nutritive value, and which therefore are to be preferred on occasions when they can conveniently be substituted for sugar or jams, are golden syrup, treacle, and black currant jam. Golden syrup and treacle are good sources of iron and calcium; loz. of golden syrup provides about atenth of the daily calcium requirement and a sixth of the iron requirement of an adult, and treacle contains about If times as much iron and calcium as golden syrup. Black currant jam is the only jam which contains appreciable amounts of vitamin C, a tablespoonful containing about a tenth of an adult’s daily requirement. As well as being one of the causes of tooth decay, too much sugar may also result in an unbalanced diet and ill health because of the eating of too few of the . protective foods—foods supplying minerals and vitamins , as well as energy A lot of sugary foods eaten in addition to the . amounts of wholemeal bread, milk,- dairy products, and other foods required to provide adequate protein, minerals and vitamins can : cause overweight just as readily as can too many fatty foods. „ - „ „ . „ , Consequently, the serving of only sweet biscuits and cakes for morning and afternoon teas and suppersa frequent habit of New Zealanders—or the inclusion of more than one cake or sweet biscuit in school lunches is not advocated, and sweets should not be eaten by anyone who is overweight. Dried Fruits ’ ■ ’ • Many, people -may be surprised to find dried fruits in eluded in the group of foods with low nutritive value,

especially as fresh fruits are an important part of the healthful diet. However, as vitamin C, the only nutrient present m fresh fruits m valuable amounts, usually is destroyed completely when the fruit is dried, much o f the nutritional value of the fruit also is lost. Being concentrated, dried fruits have value eomnarable to that of i am honey or white bread However though they have a greater nutrient + than honpv oriam thev do not conware favourably' with the white brea at present in use in New Zealand The y contain on an average less than a thir of the pro tein and B group vitamins preS ent in white bread and on i slightly more iron With the exception of dried apricots and prunes, they are also negligible sources of vitamin A; prunes and dried apricots are quite good sources of vitamin A, loz of either providing about a fifth of the daily requirement. Dried fruits are not to be recommended as a substitute for fresh fruits and vegetables, though they are useful for providing variety in puddings or for between-meal snacks for children when fresh fruits are expensive or scarce. . . Beverages ~ , , , , x , , ' . ~ Much has been written about the advantages and disadvantages of drinki n g i arge quantities of water and other beverages, though all the reliable evidence indicates that, except in certain cases of illness and’ in fevers, no advantage to health is gained by drinking excessive amounts of water or, in fact, much more than the amount of liquid required to replace adequately the losses in perspiration and other ways, The minimum requirement for these purposes .is about If pints each day. but drinking rather more than this amount is probably beneficial.

Water Though water obviously is the most natural drink, all waters are by no means equally pleasant to drink and, especially in towns or cities where it has been chlorinated, water may even taste distinctly unpleasant. Especially as no evidence appears to show that the. continual use of beverages other than water has a harmful effect on health, and as many healthy people never drink water, it is doubtful whether drinking some part of the daily water requirement as “plain water’ is necessary. There seems to be no reason why those people and it £cl"de s m ost To? Piefer tea or perhaps coffee tbnco Sp a t I]r p5 mks ’ should g

JMilk of course is one beverage which’should always be included j n be diet for it has a nutrient value unequalled by other drinks as W ell as thirst-quenching ability— fact, it can quench thirst more successfully than plain xvnfpr water.

T lea ’ vonee > ana vocoa Man has discovered three plants which contain either in their leaves (tea) or seeds (coffee and cocoa) a mixture of substances with an almost universally-acceptable and agreeable flavour and containing a mild stimulant—caffein (tea and coffee) or theobromine (cocoa). Caffein and, to a less extent, theobromine are stimulants which, taken in. moderate amounts, banish fatigue and clear the mind; in excess they cause sleeplessness.

Tannin is also present in, tea and coffee, but, as it is extracted only very slowly, unimportant amounts are present in freshly-made tea or coffee. It is the tannin which gives the bitter or “stewed” flavour ,to tea or coffee which has been boiled or kept hot in contact with the leaves or grains for a long time. Excessive tannin probably has been the cause of many types of digestive disturbances, but, as the former time-saving custom of brewing a large pot of .tea for breakfast and making it last the morning through is now rare, probably few people consume sufficient tannin to affect their health adversely. In other respects tea and coffee are of almost negligible value nutritionally, and they have no energy or calorie value. Milk coffee and tea with milk are of Value in proportion to the amount of milk they contain, and milk coffee, is an excellent alternative for people who dislike drinking milk. However, it is reasonable to postpone a child’s taking tea or coffee until he is grown up, if only because it is likely to prevent ■ his drinking milk. Though cocoa or chocolate, unlike tea and coffee, has some slight energy value, it is almost equally unimportant nutritionally because little cocoa powder is used in a cup of cocoa, most of the nutritive value being provided by the milk. Its chief advantage, especially for children, is that it makes a pleasant warm drink. Mineral Waters, Soft Drinks, and Fruit Syrups No appreciable nutritive value is contained in mineral waters, ' soft drinks, or fruit syrups. The water base in mineral waters may contain some

mineral . salts —usually those least likely to be deficient in the —and sodium bicarbonate, which may be a palliative for indigestion. The remainder are sweetened with sugar or saccharine, flavoured sometimes with concentrated fruit juices and sometimes with synthetic flavours, and impregnated with carbon dioxide under pressure; fruit juices used for flavouring are usually preservatised. The flavourings and preservatives used in the preparation of such drinks have been shown by careful experimentation to be harmless in the amounts present, but they are, like tea and coffee, negligible sources of minerals and vitamins. Often they contain quite large amounts of sugar and acid, which, if they are used too frequently, may induce tooth decay. In addition, their use should not be allowed to preclude the consumption of adequate amounts 'of milk by children. In bottled or tinned fruit juices, on the other hand, the vitamins are usually well conserved, so that, if desired, those made from fruits of higher nutritive value, such as oranges and pineapples, may be used occasionally to supplant fresh fruit on the menu.

Alcoholic Drinks Probably very few consumers of alcoholic beverages delude them-, selves that they take them for the benefit of their health. Apart from their alcohol content, most alcoholic drinks are little different from soft drinks in their nutritive value.

The energy value of beer and wines is not greatly different from that of milk, but they are negligible sources of other nutrients. Beer has a greater nutritive value than wine, containing about 10 times as much vitamin B and protein, but even then it contains only

about a tenth as much of these nutrients as milk. Spirits have no nutritive value. The effect of alcohol on health has been much discussed, and the attitude of the nutritionist has perhaps been summarised best by Professor V. H. Mottram, a noted English nutritionist, who states in “Human Nutrition” that: “While the danger of all but the strongest alcoholic drinks has been exaggerated, alcohol is, none the less, a narcotic depressent, which brings about its effects by paralysing the higher psychological characteristics.” “Under the influence of alcohol, accuracy, avoidance of accident, tactful handling of colleagues and subordinates, observance of discipline, punctuality, reticence in matters of confidence, are all jeopardised,” states a British Government publication called “Alcohol: its Action on the Human Organism.” : Medical practice, as judged by the greatly-decreased use of alcoholic drinks in hospitals in London during the past few decades, is against its use in medicine. Dietitians recognise that, if patients are really miserable without their drink, letting them have it in moderation is better than forbidding it. Professor Mottram concludes that: “In general the nutritionist is mildly contemptuous of processes that waste quite a percentage of the food values of cereals and fruits in order to make expensive beverages of a doubtful dietetic value, however pleasant they may be.”

Proprietary Foods . No matter how good they are claimed to be, proprietary foods usually are expensive luxuries.: They include all the vegetable and meat extracts, malt and malted foods , and drinks, vitamin

preparations, and yeast preparations. Though many of them . are now good sources of one or more vitamins and minerals, they are not necessary constituents of a well-balanced diet. They are often very useful in cases of illness, and some of them, especially yeast and meat extracts and malted milk preparations, are popular and useful for' sandwich fillings, drinks, and flavouring foods, but used in these ways they usually do not contribute much toward the daily vitamin or mineral requirement of the body. Vegetable and Meat Extracts As well as the substances responsible for their flavour, vegetable extracts contain quite a large amount of vitamin Bj or thiamine and smaller amounts, of riboflavin compared with equal weights of other foods. However, in the amounts normally used they provide very little of these vitamins. For example, a teaspoonful of vegetable extract, which ' is a very .large serving, provides about a fifteenth of the daily vitamin Bi requirement of a moderately-active man and thus is comparable in this respect: to a thin slice of wholemeal bread (loz.). Meat extracts contain much less vitamin B n but proportionately more of the other vitamins in this group—riboflavin and niacin. One teaspoonful may contain about a tenth of the daily niacin requirement. Their greater popularity as : flavourings in -soups, gravies, and drinks also means that when they are used frequently meat extracts make a useful contribution toward the daily requirement of these vitamins. Yet their: cost,; their, complete lack of energy value, 'and the fact -that .they contain no protein make them i expensive; sources' of these vitamins compared with wholemeal bread; milk, and even meat. !; > I ; |ii : i

Yeast Preparations Research has shown the nutrient content of live yeast cells, whether dried, compressed, or in liquid form, to be unavailable to the body because the yeast cells resist digestion and pass through the body unchanged. Therefore, apart from their possible value as laxatives, these ’ preparations are useless nutritionally. It has even been shown that sometimes they may absorb vitamins from the other food eaten and therefore rob the body of its vitamins. Pasteurised yeast and yeast preparations in which the cells have been killed by heat have a food value comparable to that of vegetable extracts. Malt Extracts and Malted Foods Malt extracts and malted foods are not' nearly as nutritious as they are often supposed to be. Malt extract contains sugar, maltose ' and dextrin (both products of the partial digestion of starch), and a small amount of diastase, which changes starch to sugar, but which is of doubtful value for even the confirmed dyspeptic. It contains only small amounts of the B group of vitamins and insignificant amounts of other nutrients, so it is little better then golden syrup or treacle as a food, if as useful. When cod-liver or halibutliver oil and orange juice are added it is of slightly greater food value, but most nutritionists would recommend that the fish oil itself and fresh fruit are preferable sources of vitamins : A, D, and C. Malted milk and other dried milk or. milk and cocoa preparations have a much higher food value than malt extract, ■ though they are relatively expensive compared with plain ■ dried milk or milk cocoa. 'However, if they, make I ' otherwise-unacceptable ! I milk palatable, there is some justification for their use in milk; drinks.

Wheat Germ and Wheat-germ Preparations

Like other special foods rich in nutrients, wheat germ is not essential to a well-balanced diet, but because when bought loose it is a much cheaper source of nutrients than patented foodstuffs, there is more justification for its inclusion. When wheat. germ is incorporated in cereal puddings, porridge, or bread its nutrient value is all retained; in baking powder breads, scones, biscuits, and puddings quite a lot of the thiamine may be destroyed, so that, unless the flavour of wheat germ is specially preferred in these foods, this is a wasteful way in which to use it.

Packeted wheat germ is often more easily obtainable, but has no special advantages from the nutritive point of view, for loz. of either (1 tablespoon) provides more than an eighth of the ' daily vitamin B, requirement and fair amounts of the other vitamins in this group. It also contains much vitamin E, a vitamin which is, however, probably supplied in adequate amounts by all but the poorest diets or is able to be made by Man himself, just as most animals are able to make their own vitamin C.

Vitamin Preparations

For most people vitamin preparations are neither necessary nor desirable. It is far better to eat good food such as milk, eggs, fruits, and vegetables, for they provide other nutrients as well as vitamins,. and nutritionists admit freely that much has still to be found out about the nutrients, including some perhaps as yet undiscovered, essential for health and the amounts most beneficial to mankind. Until this is known with certainty, it is better to obtain them from a mixture of natural foods, which are more likely to contain them all.

Condiments

Though the part played by condiments in the diet belongs more to a study of the art than of the science of food, no one will deny that they are of great importance.

Only the person condemned to a saltfree diet can savour the true value of salt in cookery; the menu lacking such common flavourings as vinegar, onions, parsley, pepper, and spices would be equally wanting in flavour. Some of them contain vitamins and minerals, but they are all used in such small amounts that they make no significant contribution to the need for either nutrients or calories.

Influence on Eating Habits

In these articles the nutritional value of most of the common groups of foods and the need for including in the diet adequate amounts of the protective foods have been discussed. The other foods, because they serve to garnish the plain, everyday milk, bread, or potatoes are useful, too, for they can transform the dullest meal into a repast fit for a gourmet. However, like the garnish on a salad, they should not be overdone, especially for children, for they may cause the development of eating habits which preclude the consumption of adequate amounts of the foods essential for health and fitness.