La Mer and Campbell have presented some evidence to show that the antis...o...b..tic vitamine has a direct effect upon the adrenal glands. In their scurvy cases they find definite evidence of the enlargement or hypertrophy of this organ. Whether it affects other organs or not it remains to be shown.
CHAPTER VII
HOW TO UTILIZE THE VITAMINE IN DIETS
In the preceding chapters it has been the aim to present the findings of the princ.i.p.al workers in the field. In attempting to summarize the work of so widely scattered a group as are now engaged in vitamine research it is impossible to cover completely the many investigations and it is inevitable that some work will have been overlooked, but the foregoing covers at least the princ.i.p.al data on the subject. What is the bearing of all this information on human behavior and what lessons can the layman draw from it that is of direct application to him? Let us first consider this question from the dietary viewpoint.
I. INFANT NUTRITION
The limited character of the infant"s diet has made the consideration of vitamine content in his diet much more important than in the case of the adult with the latter"s wide variety of choice. It is evident from the previous data that a growing infant must not only be provided with a sufficient supply of calories, nutrients and salts, but must also have a liberal supply of the three vitamines. Milk has in general been cla.s.sed as adequate in all these features, but the vitamine researches have forced us to reconsider our views in regard to this staple.
The first point to be borne in mind is that the vitamine content of either cow or human milk is dependent primarily upon the food eaten by the producer of the milk. In other words milk is merely a mobilization of the vitamines eaten and if the diet is to yield vitamine-rich milk it must itself be rich in these factors. Many a cow produces milk low in vitamine content and the same is true of nursing mothers. There are many "old wives" prejudices in regard to what food a lactating mother may eat and unfortunately many of these prejudices are extremely injurious and false.
One of them is the prejudice against green vegetables. Experience has shown that under ordinary conditions such vegetables are well tolerated by the mother and from their content of vitamine it is evident that they are suppliers of these factors. In the case of the cow the fact that cereals are poor in some of the vitamines and green gra.s.ses rich therein, teaches a lesson that bears directly upon winter feeding of cattle if the milk supply is to be used for infants. We need a series of diets and cattle foods for just this purpose of insuring the proper vitamine content in milk. The preceding tables will enable one to develop such diets fairly satisfactorily, but more data is urgently needed.
The second point in regard to milk lies in the effect of pasteurization.
This measure is now well nigh universal and in America at least has played a tremendous part in the reduction of infant mortality, especially during the summer months. At present, however, we know that this treatment while removing dangerous germs may also eliminate the antis...o...b..tic factor. The sensible att.i.tude then is to recognize this fact and if a clean whole milk is not available retain the pasteurization and meet the vitamine deficiency by other agents. Such agents are orange juice and tomato juice and experience has already shown that these juices can be well tolerated by infants much earlier than used to be thought possible.
While the pasteurization does not appreciably affect the content of "A" or "B" vitamines, the variability in content of these vitamines in milk indicates that it may at times be necessary to supplement them in the diet. In this connection it must be borne in mind that cereals vary widely in content and cannot be, as they often are now, considered equivalent in growth stimulation power. This is a subject that needs special attention on the part of vitamine experts and diet.i.tians and finally by the food manufacturers. A good vitamine-rich cereal combination would form an excellent adjuvant to infant dietaries after they reach the age of tolerance to such a diet. But even before that time the expressed juice of various vegetables as well as fruits is found to be well tolerated when mixed with the milk or given separately, and carrot and spinach juice are now being used in this connection with good results. These juices like orange juice contain the B type in abundance and there is no doubt that in their stimulation to the appet.i.te they play an important part in making the desirable daily gain.
Fortunately for the layman he has in the scales a good indicator of the normal progress of his child and so long as growth is normal he can fairly a.s.sume that the diet is adequate but if the scales say otherwise it is time for him to seek advice and then he is wise who insures that his medical adviser knows the newer aspects of nutrition. The parent can do this only by proper selection, but with a little knowledge he can soon satisfy himself as to whether his pediatrist is the right sort and it is one of the purposes of this text to bring home to the layman his responsibility in this matter.
There has grown up in this country a great regard for prepared milk subst.i.tutes in infant feeding and a wide usage of condensed milks, reinforced milks, diluted milk formulae, etc. All such preparations must be examined anew in the light of the vitamine discoveries and unless the given preparation can show a clean bill of health in vitamine content, it should be either discarded or properly supplemented.
As children grow up, it is fortunate that in their wider choice of dietaries the danger of vitamine deficiency decreases. But even in childhood it is unsafe to rely too much on chance. In this country there are well deserving movements on foot to attract the parents of the community to the necessity of attention to simple standards of growth progress, and clinics for this purpose are appearing in increasing numbers with each year. Such movements are to be most heartily approved. It is also possible in these measures to not only build better children, but to make the children themselves intelligent in their rejection of unsuitable combinations and in that way not only conserve their own health, but provide an educated body of citizens to pa.s.s on the knowledge to future generations. In a school in New York City I recently had occasion to discuss the school lunch room and its offerings with the children of the school in the light of vitamine discoveries. The keenness and intelligence shown by the children in the discussion that followed has convinced me that in this matter of vitamines the children themselves can be relied upon to a.s.sist materially in the matter of better food combinations and intelligent selection.
Finally it must be noted that one of the most common of infant deficiencies is the failure of the bones to lay down lime. The effect of this failure is commonly described as rickets. The British workers consider that this deficiency is a lack of vitamine "A." Their views have been set forth at greatest length by Mellanby, the princ.i.p.al worker in this subject. While this view is still debatable and in this country it is not yet accepted, one fact has come out in the controversy and that is the remarkable value of cod-liver oil as a preventive of rickets. It may be that the power of the oil is due to its "A" vitamine content in which it is known to be rich, or it may be due to a new vitamine, but the fact that the oil is a preventive in this respect gives the pediatrist another agent to insure normal growth. The various views on the causes of rickets are set forth more in detail in Chapter VIII.
II. ADULT DIETS
A study of the dietary habits of various sections of the United States shows that there is a very general tendency on the part of the majority of the people to confine their foods to a meat, potato, and cereal diet. The use of salads is looked upon by many sections as a foreign affectation and too little attention is paid to the value of eggs, milk and cheese. Enough has been said already to show that these latter articles have much more than an esthetic value and one of the missions of the nutrition expert must be to show the people why dairy products and salads must become features in the every-day meals of the every-day people. And even if the salads are still unappreciated, it is necessary that cooked green vegetables occupy more of a position in the menu than is too often the case.
There has recently appeared a crusade for the eating of yeast cakes. The claim made for their use rests on a perfectly firm basis, they are rich in the "B" vitamine, the proteins of the yeast cake are of good quality and the cake contains no ingredients poisonous to man. Many people are reporting beneficial effects from their use. Is there any lesson to be drawn from this experiment? I feel that the very fact that benefits have resulted from this yeast feeding is excellent evidence of lack of the vitamine in the diets of the people affected and a clear argument that the dietary habits of many people need adjustment to a higher vitamine content. Whether it is necessary to use yeast cakes or any other concentrate of vitamine, depends entirely upon whether the ordinary diet is lacking in these factors and my first advice in the matter would be to make if possible a selection of the vitamine containing foods and see if normal conditions did not result before utilizing foods whose taste is not pleasing or which are taken as medicine. For it is an old experience that medicines will be taken only so long as the patient is sick and perhaps it is just as well so. In other words I believe it is possible with intelligent selection based on such tables as are given in Chapter IV for people to secure from the butcher and the grocer all their requirements of these vitamines as a part of their regular palatable diet. To those who have neglected this selection and find remedy in concentrates, that fact should lead them to reconstruct their diet rather than persist in dependence on the medicine to correct faulty diet. In other words the same arguments apply to the use of medicinal concentrates of vitamines as applies to the use of laxatives. At times these substances are very valuable as cures, but it is better by far to so regulate the dietary habits as to avoid the necessity for their use.
Another phase of this matter that promises to develop in the near future as a result of the vitamine hypothesis is a reform in food manufacture.
There has been a strong tendency during the past two decades to "purify"
food products. The genesis of this tendency is to be found in a highly laudable ambition to force the manufacturer to eliminate impurities and adulterations and provide clean, wholesome, sanitary food. Unfortunately in attempting to meet this demand on the part of the public, the food manufacturer has sometimes neglected to seek advice from the nutrition expert and the latter has failed to appreciate the need of advice. The net result has been to discover that Nature is often a better chemist than man and has a much better knowledge of what man needs in his diet than the chemist. The chemist employed by the manufacturer has, as a result, gone to such a limit in his development of purification methods as to often eliminate the essential nutrients and the result has been foods that will stand a.n.a.lysis for pure nutrients, but which will not stand Nature"s a.n.a.lysis for dietary efficiency. As a secondary result of this tendency we have acquired habits that in many cases must either be broken or must have grafted on to them other habits which shall remedy the defective ones.
Take the milling of wheat as an example. Nature put into the wheat grain most of the elements needed by man and in the early days he was content to grind up the whole grain and find it palatable. The craze for purity as expressed by color has gradually replaced this whole meal wheat with a beautiful white product that is largely pure starch with a few of the proteins retained. And the princ.i.p.al protein retained lacks one of the greatest essentials for growth while the vitamines have all been practically eliminated with the grain germ. Intelligence tells us then that if, having formed the habit, we will persist in our appet.i.te for white flour we must see to it that the protein deficiency of the latter and its lack of vitamines is compensated for by supplementing the diet with the food-stuffs in which these are rich. We may in other words retain our bad habits in taste if we will graft on to them the attention to the eliminated factors and their subst.i.tution in other form.
In general then, the adult needs to review his feeding habits and a.n.a.lyze them in the light of our new knowledge. For this purpose the tables of Chapter IV supply data useful so far as vitamines are concerned, but it will be perhaps worth while to repeat here some of this data in more generalized form.
_a. Sources of the "A" vitamine_
Its most abundant sources are milk, b.u.t.ter, egg yolk fat, and the green leaves of plants usually cla.s.sed as salads. Cabbage, lettuce, spinach and carrots contain this substance in considerable quant.i.ty. The germ of cereals is fairly rich in the factor, but the rest of the grain is deficient and white flours are therefore poorer than whole meals in this respect. Cooking temperatures have little effect on this vitamine and hence little attention need be paid to cooking temperatures as far as this vitamine is concerned.
_b. Sources of the "B" vitamine_
Its princ.i.p.al sources outside of yeast are the seeds of plants and the eggs and milk of animals. Meat contains relatively little of this substance but glandular organs such as the liver and pancreas are fairly rich in it. In the seeds the distribution is general throughout the whole body of the seed in the case of beans, peas, etc., but in the cereal grains it is largely restricted to the embryo portion and hence a high degree of milling tends to reduce the per cent of this factor in any highly milled cereal. White flour and polished rice are notable examples of deficiency of "B" vitamine due to this milling process. Fruits such as oranges, tomatoes, and lemons are good sources and there is a fair amount present in the apples and grapes and other common food fruits. Many vegetables show it in fair abundance, notably potatoes, carrots, and turnips, but the rule is not general for beets are extremely poor in this factor. Nuts are also good sources. Eggs, milk and cheese contain it in fair abundance. Cooking temperatures have little effect on this type if the temperature does not climb above the boiling point and if the cooking water is not "alkaline." In the latter case it becomes necessary to determine the extent of destruction and either eat enough to insure protection, or reform the method of cookery.
_c. Sources of the "C" vitamine_
Its richest sources are vegetables such as cabbage, swedes, turnips, lettuce and watercress; fruits such as lemons, oranges, raspberries and tomatoes. Certain of the vegetables such as potatoes have a substantial value in this respect, but meat and most prepared milks are low in antis...o...b..tic values. The susceptibility of this vitamine to drying, heat and alkali, make it necessary to scrutinize your cooking methods very carefully in order not to ruin a good source by a poor preparation of it for the table.
CHAPTER VIII
AVITAMINOSES OR THE DISEASES THAT RESULT FROM VITAMINE DEFICIENCIES
A survey of the vitamines would be incomplete without a discussion of the vitamine deficiency diseases in particular, though many of the facts already cited obviously bear on the treatment and prevention of such diseases.
The idea of "avitaminoses" or vitamine deficiency as the cause of a disease of a specific nature was set forth in detail by Funk in his book _Die Vitamine_. In his discussion of this view he suggests several types that would, he felt, on examination prove to be due to the absence of a vitamine in the diet. Of these predicted types beri-beri was the only one to be established in 1913. Scurvy has now been added to the fold and rickets or rachitis seems well on the way to acceptance though the specific vitamine absent in this case is not yet positively identified.
Pellagra still resists the efforts of the vitamine hypothesis to bend it to that theory and its etiology is still obscure.
I. BERI-BERI
This disease while specifically confined to the oriental in the mind of the student can be justly considered of much wider distribution for the mild forms of malnutrition a.s.sociated with a deficiency in the "B"
vitamine are less acute manifestations of this disease. The disease is not likely to become marked in well nourished districts in its acute form, but in famine districts its incidence is always possible. It would be more than possible were it not for the fact that famine tends to eliminate the highly milled cereals and throw the people back on to the whole grain, peas and beans, which are rich in the preventive factor. But when for any reason diets become limited extra attention is demanded in regard to their selection and preparation. The main characteristics of this disease have already been fully covered in what precedes and need not be repeated here.
II. SCURVY
This disease, like beri-beri has already been fully discussed in what precedes. One of the striking discoveries of this subject has been the retreat from favor of the time-honored lime juice which is now found to be much less potent than oranges, lemons, or even canned tomato juice and which on preservation loses practically all its potency. In the modern hospital, cases of scurvy rarely appear outside of occasional infant cases and it might appear that the problem of scurvy prevention is peculiarly that of the sailor, the explorer and the army rationer. Nevertheless an insufficient supply of the "C" vitamine may r.e.t.a.r.d growth and well being in the individual without manifesting itself in its more acute form of scurvy. In a recent review Hess states: "It is hardly an exaggeration to state that in the temperate zones the development or non-development of scurvy depends largely on the potato crop." "This is attributed in part to the fact that the potato is an excellent antis...o...b..tic, but to a greater extent because it is consumed during the winter in amounts that exceed the combined total of all other vegetables." To the public and to the food purveyor there is a definite problem in how to best supply the preventive and how best to concentrate and preserve the sources of this vitamine without injury to its potency. The following observation is therefore appended as bearing on this point. In the absence of fruits or other high potency sources it is possible to develop this factor in cereal grains by the simple expediency of sprouting. If seeds are soaked in water for twenty-four hours and then kept moist for from one to three days with the free access of air, sprouts will develop whose content of the antis...o...b..tic vitamine is comparable to that of many fresh vegetables, even though the dry seeds themselves have little of this factor. In other words the germination process is a synthesiser of the vitamine. This observation may be of value where fruits and vegetables are scarce or expensive. On account of cooking effects, it cannot be too often reiterated that raw fruits, vegetables and salads, are of more value than cooked forms of these same sources and that drying processes are extremely destructive where heat enters into the drying process. Vacuum drying seems to be much less destructive and it may be possible to develop the drying of vegetables to a point where retention of this vitamine factor is practical. At present all dried vegetables should be regarded with suspicion as a source of vitamine "C." Expressed juices may often be used where the whole vegetable is scarce or incompatible and this fact is one to be borne in mind by the worker in famine districts.
III. RACHITIS (RICKETS)
This disease is engaging the attention of many workers on both sides of the Atlantic at the present time. In England the princ.i.p.al contributor is Dr. Mellanby, who has acc.u.mulated evidence which he believes indicates that the preventive factor is the A vitamine. This view is not yet accepted as conclusive by the American workers. McCollum, Howland, Park, and others at Johns Hopkins University have experimented with various rickets-producing diets and while the princ.i.p.al deficiency in these diets seems to be Ca salts and the A vitamine they do not consider that the disease can as yet be traced to deficiency in any one factor. Hess has called attention to several new features and the significance of some older measures. He has shown on the one hand that cod-liver oil is almost a specific remedy for the disease but that this remedy is not replaceable by other rich sources of the A vitamine. He has also recently shown that hygienic measures may have an influence. Schmorl showed that the disease was seasonal, a high rate maintaining in the winter months and a lower rate in the summer months. Hess has recently reported beneficial results from use of the ultra-violet rays which he uses as a subst.i.tute for sunlight. The results seem to confirm Schmorl"s view that the sunlight of the summer months is a preventive factor. He has also suggested that the specific effect of the cod-liver oil might be due to a new vitamine, Vitamine D? On the other hand Zilva and Miura in England have recently shown that crude cod-liver oil is something like two hundred and fifty times as rich in vitamine A as b.u.t.ter fat, which tends to support the British view that the A vitamine is the antirachitic factor.
Sherman and Pappenheimer have recently shown that the phosphates exert a marked preventive effect on rickets and suggest that the utilization of the calcium by the individual may be determined in part by this factor.
The views in brief are now in an extremely chaotic state and it is impossible at present to determine whether rickets is a true avitaminose or a consequence of deficiency in a series of factors. It is however certain that the disease in its subacute forms is extremely wide-spread among infants and that its prevention can be most easily secured by the addition of cod-liver oil to the diet. In this procedure warning is necessary that the cod-liver oil be as pure a product of oil as possible, since the market preparations are often almost devoid of the true oil and hence of the curative agent.
IV. PELLAGRA
This disease has been the subject of exhaustive inquiry and study on this side of the Atlantic and the findings of the various investigating boards have added much to the prevention and cure of the scourge, but have failed as yet to agree on any one etiological factor. The best recent review of the current findings is to be found in an article by Voegtlin published as Reprint 597 of the Public Health Reports of the United States Public Health Service. His conclusions may be quoted in full as representing the latest summary of evidence now extant:
1. The hypothesis that there is a causal relation between pellagra and a restricted vegetable diet has been substantiated by direct proof to this effect and has led to results of considerable practical and scientific value.
2. The metabolism in pellagra shows certain definite changes from the normal, which point to decreased gastric secretion and increased intestinal putrefaction.
3. In the treatment and prevention of pellagra, diet is the essential factor. The disease can be prevented by an appropriate change in diet without changing other sanitary conditions.
4. A diet of the composition used by pellagrins prior to their attack by the disease leads to malnutrition and certain pathological changes in animals, resembling those found in pellagra. A typical pellagrous dermat.i.tis has not been observed in animals. Pellagrous symptoms have been produced in man by the continued consumption of a restricted vegetable diet.
5. _The nature of the dietary effect has not been discovered_, although certain observations point to a combined deficiency in some of the recognized dietary factors as the cause of the pellagrous syndrome.