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VITAMINE, the term now employed to designate certainsubstances contained in foods. The exact nature of thesesubstances is not known, but they have been shown to be necessaryto the normal development of young animals (includingchildren) as well as to the maintenance of health and well-beingin adults. They are very labile substances which, existingabundantly in raw foods, especially in uncooked fruits andvegetables, become seriously attenuated or altogether destroyedby cooking, desiccation, decortication and other refining processes.There are probably a great many vitamines in natural foods —live or quick foods, as they are called — but up to the time ofwriting three only have been isolated. These are (1) theanti-scorbutic factor; (2) the water-soluble B.; (3) the fat-soluble A.
The Anti-Scorbutic Factor. — As long ago as 1734 J. E.Bachstrom observed that the disease known as scorbutus or scurvyappeared to be related to the ingestion of salted, preserved anddried foods. The disease in question was alarmingly prevalentamong mariners on long distance sailing vessels, and the Britishnavy was annually decimated by this scourge. The introductionof fresh vegetables and fruits into the dietary of the sailors wasfound to afford them complete protection against the disease, butthe knowledge thus empirically gained was not followed by anyscientific investigation, and though the door was thus widelyopened to the discovery of vitamines, these important substanceswere destined to lieperdu for nearly 200 years. This anti-scorbuticfactor is the most fragile of the three which have so far beenisolated. It is present in large quantities in all uncooked fruitsand vegetables, and it is interesting to note that the popular ideathat foods which have been kissed by the sun have a greatervalue than those which have not, finds some justification in thefact that vegetables grown above ground are much richer in theanti-scorbutic factor than root vegetables. This factor is wellrepresented in fresh milk, but boiling, pasteurization, or evaporationcompletely destroys it.. The activity of the anti-scorbuticfactor is much increased by germination; thus, beans, peas, orthe grains of wheat or barley in the ordinary dry quiescent statecontain no anti-scorbutic factor, but if they be placed in waterand allowed to germinate, they immediately acquire this vitaminein large quantities. There is a practical application of thisinteresting fact which should not be lost sight of by travellers ininaccessible regions.
The Water-Soluble B. — Prof. Gowland Hopkins of Cambridgepublished in 1912 an article entitled “Feeding ExperimentsIllustrating the Importance of Accessory Factors in NormalDietaries,”[1] in which he called attention to the serious effectsupon the health of animals which resulted from the absence fromtheir food of certain hitherto unrecognized principles. In thefollowing year Casimir Funk[2] claimed to have isolated a “FactorX” which corresponded to the absent principles described byHopkins to which he gave the name of Vitamine, in the mistakenbelief that the factor in question contained an amino-acid. Inspite of its faulty derivation the name caught on, and the wordvitamine is now employed to include any of those essentialsubstances which Hopkins unfortunately described under theterm “accessory.” The experiments of these two observersshowed that the absence of the factor now known as theWater-Soluble B. was the cause of the disease known as beriberi, whicha Dutch physician, Dr. C. Eykman, had in 1897 associated withthe custom of eating polished or decorticated rice by the natives,to the exclusion of all other foods. Beriberi is a disease of thenerves, and it was found that other similar affections of thenerves, pellagra for example, could be experimentally producedby withholding this vitamine, and cured by reinstating it in thedietary; hence the term “anti neuritic” by which it is sometimesknown. This factor is essential to the normal growth, developmentand well-being of young animals. It is present in greatabundance in all quick or natural foods, in grains and eggs. It isalso present in the brain, liver, sweetbread and kidneys of animals,whereas from muscle or ordinary meat it is relatively absent.Yeast contains this vitamine in large quantities. In thevegetable kingdom, the leguminosæ afford it, uniformly distributedthroughout their substance; whereas in cereals it is confined tothe outside covering; hence the importance of unpolished riceand whole meal bread. It is soluble in water, especially in slightlyacidulated water, and in alcohol, but not in fats. It resists arelatively high temperature; it is present for example afterboiling for a short period, but is destroyed at 120° C.
This vitamine, as indeed the whole conception of vitamines ingeneral, was first described in 1901 by Dr. Eugene Wildiers ofAntwerp (1878-1908) under the name of Bios.[3] In a paper whichappeared inLa Cellule (Louvain) on April 2 1901 entitled“Nouvelle substance indispensable au développement de lalevure,” this young Belgian observer set forth a good deal of theknowledge which we now possess, but no notice was taken of hiswork, and his conclusions were arrived at independently by adifferent route about 12 years later.
The Fat-Soluble A. — In the year 1913 the third vitamine wasdescribed by McCollum and Davis.[4] Its absence was shown toprovoke a disease of the eyes, characterized by œdema of thelids, ulceration of the cornea, blindness and ultimately death.These lesions, even when in an advanced state, were cured by theexhibition of the vitamine. The absence in some degree of thisfactor is held responsible by some for the disease known asrickets. Its presence is certainly necessary to the growth andnormal development of young animals. It is found (a) in certainanimal fats,i.e. milk, butter and glandular tissue; (b) in thegreen leaves of edible plants. It is thus interesting to note thatthough present in essential organs or so-called “noble” tissues,it is absent from connective tissue and reserve tissue, such as lardor the subcutaneous animal fats. Olive oil and other vegetableoils do not contain this vitamine, whereas cod-liver oil containsit in large quantities. Fat-Soluble A. is soluble in oil, but not inwater. It resists high temperature better than the other two.
Such was the state of our precise knowledge in 1921 concerningthese elusive substances. If only from the confused and cacophonicnomenclature, it is evident that this knowledge was still in avery embryonic state. That there is, in this matter, a very widefield of interesting and fruitful research awaiting us is obviousfrom the fact that the discovery of the vitamines has entirelyaltered our conceptions of the causes and origins of disease.Until lately disease was regarded as a sin of commission by someunseen and subtle agency; the vitamines are teaching us to regardit in some degree at any rate as a sin of omission on the part ofcivilized or hypercivilized man. By our habit of riveting ourattention upon microbes and their toxins we had sadly neglectedthe side of the question which concerns itself with our owndefences. We sterilized our children's milk against the bacillus,and in so doing we deprived it of its vitamines and thus loweredthe resisting power of the victim, not to one microbe only, but toall. The importance of vitamines has taught us that thenaturally nourished child is practically immune from the majorityof the diseases which in spite of our bacteriological and hygienicknowledge have been raising the infant death-rate to a figurewhich was as surprising as it was appalling. But it is to beremembered that in order to attain to this immunity a child mustbe born healthy; it must have been suitably nourished during itsintra-uterine life, and this can only be attained by feeding theprospective mother upon foods which contain the necessaryvitamines in such an abundance as will satisfy the physiologicalneeds of two. The gross diseases due to absence of vitamines,such as scurvy, beriberi, pellagra and xerophthalmia, called the“deficiency diseases” (maladies de carence) are characterized bysymptoms which are acute and unmistakable, but it is certainthat long before these acute symptoms appear there will have beena general ill-defined departure from normal health, called by theFrenchcarence fruste orhypo-carence, and the condition maynever pass beyond this stage. It is thus not only futile butactually dangerous to seek to estimate, as has often been done,the minimum amount of vitamine which will insure protectionfrom obvious disease. What is required is not the minimum butthe optimum. Amongst these conditions ofhypo-carence maybe mentioned the majority of the maladies due to the deficientaction of the internal secretory or endocrine glands, such as thethyroid, thymus, supra-renals, pituitary, gonads and others,which have already been shown to suffer severely from deprivationof vitaminous foods. In the same category ofhypo-carenceare also to be placed many of the so-called metabolic diseasessuch as gout, arthritis, diabetes and others. These may beoccasioned directly by the vitamine deficiency, or indirectly bystarving one or more of the endocrine glands of the all-essentialprinciples. As might easily be supposed, this relative lack ofvitamines is peculiarly liable to show itself in the gastro-intestinaltract. Digestive difficulties and intestinal inertia, appendicitisand colitis have been shown in a great number of cases to havebeen due to a lack of vitamines in the ordinary foods, a fact ofwhich anyone may convince himself in the matter of the widelydistributed disease known as intestinal stasis or chronic constipation.It has often been remarked that dental caries or defectiveteeth is an evil which has seemed to be very much on the increaseduring the last 20 years; the period, that is, during which all freshand unsterilized foods have been withheld from the young inorder that they may be fed on devitalized pap which, in additionto requiring no mastication, is, by boiling and other culinaryprocesses, completely deprived of the vitamine content so necessaryto the proper development and eruption of the teeththemselves. Vitamines have already revolutionized our ideas ondietetics. The erstwhile stereotyped proportions of the proximateprinciples, proteins, carbohydrates, fats and salts which wereconsidered essential to bodily health have been so altered by thediscovery of the vitamines that the whole question will have to beinvestigated and studied afresh, and the ineffable theory ofcalories which was based on the curious assumption that thebehaviour of food in the human body was identical with itsbehaviour in a test-tube, will retire to the limbo of things wellforgotten. The discovery of the vitamines presents would-bescientists with a much-needed lesson in humility. It reminds usthat, in evolving man, Nature provided him with the foodsnecessary to his growth, development and well-being, and thatin interfering with these natural foods by cooking, sterilizing andrefining, he has sacrificed their efficacy, sometimes to his greed,but more often to his arrogant assumption of superior knowledge,with the result that he has not only promoted the prevalence ofpreventable disease, but has actually created others which butfor his misdirected energy would have had no existence.
References. Report on Vitamines, Medical ResearchCommittee (British Government, 1919); Weill and Mouriquand,Alimentation et maladie par carence (1919); Dr. G. Houbert,La questiondes vitamines (1920); Raoul Lecoq,Les nouvelles theoriesalimentaires (1920).
(L. Wi.)
