[The complete text of the Lectures, with illustrations, may be obtained in pamphlet form, price 2s. 6d., on application to the Secretary, Royal Society of Arts, John Street, Adelphi, London, W.C.2.].
VARIETY OF DISEASE IN IMPROPERLY FED ANIMALS.
During the last eighteen years of my experimental work in India I used many thousands of animals — rats, pigeons, fowls, rabbits, guinea-pigs and monkeys– feeding them on diets not synthetically prepared from purified foodstuffs but from foodstuffs in common use by the people of India; my purpose, as previously hinted, being to learn what relation the food used by the people had to the diseases from which they suffered. At the risk of being tedious I shall now enumerate the maladies I have encountered in these improperly-fed animals, leaving out of count such manifestations of ill-health as weakness, lassitude, irritability and the like, which are commonly met with in malnourished animals.
Here is the list. Skin diseases: loss of hair, gangrene of the feet and tail, dermatitis, ulcers, abscesses, oedema. Diseases of the eye: conjunctivitis, corneal ulceration, xerophthalmia, panophthalmitis, cataract. Diseases of the ear: otitis media, pus in the middle ear. Diseases of the nose: rhinitis, sinusitis. Diseases of the lungs and respiratory passages: adenoids, pneumonia, broncho-pneumonia, bronchiectasis, pyothorax, pleurisy, haemothorax. Diseases of the alimentary tract: dental disease, dilatation of the stomach, gastric ulcer, epithelial new growths in the stomach (two cases of cancer), duodenal ulcer, duodenitis, enteritis, colitis, intussusception and a condition of the lower bowel suggestive of a precancerous state.
Diseases of the urinary tract: pyonephrosis, hydronephrosis, pyelitis, renal calculus, nephritis, urethral calculus, dilated ureters, vesical calculus, cystitis, incrusted cystitis. Diseases of the reproductive system: endometritis, ovaritis, death of the foetus in utero, premature birth, uterine haemorrhage, testicular disease. Diseases of the blood: anaemia, a pernicious type of anaemia, Bartonella muris anaemia. Diseases of the lymph and other glands; cysts, abscesses, enlarged glands.
Diseases of the endocrine glands: goitre, lymph-adenoid goitre, adrenal hypertrophy, atrophy of the thymus, haemorrhagic pancreatitis (very occasionally). Diseases of the heart: cardiac atrophy, cardiac hypertrophy, myocarditis, pericarditis, hydropericardium. Diseases of the nervous system: polyneuritis, beri-beri, degenerative lesions. Diseases of the bone: crooked spine, distorted vertebrae (no work was done on rickets — a known “deficiency disease”.) General diseases: malnutritional oedema, scurvy, prescorbutic states.
All these conditions of body, these states of ill-health, had a common causation; faulty nutrition, with or without infection. They are the clinical evidence — the signs and symptoms — of the structural and functional changes in organs or parts of the body that result directly or indirectly from faulty nutrition. It will be noted that local infections and maladies of a chronic and degenerative kind are conspicuous amongst them.
These maladies are, in short, the symptoms of malnutrition as observed in animals fed on faulty diets — some of them admittedly very faulty– in use by human beings, or on food materials in use by them. It is reasonable, then, to expect that maladies of a similar order are likely to result from malnutrition in human beings. In my next lecture I shall endeavour to make clear how it is that food of improper constitution leads to that disturbance of structure or function of organs or parts of the body which is “disease”.
RELATION OF CERTAIN FOOD ESSENTIALS TO STRUCTURE AND FUNCTIONS OF THE BODY.
MINERAL SALTS.
The mineral constituents of food consist of some twenty elements of which eleven– previously enumerated (Lecture I)– are definitely known to be essential to vital processes. They are all intimately related one to another by complex chemical combinations and interactions, so that it is difficult to separate the functions of one from those of another. In general these functions are to provide building-materials for the fabric, and to regulate various functions, of the body.
NATIONAL HEALTH AND NUTRITION.
If we look upon ” infection” of whatever kind, be it due to microbe, protozoa, metazoa, or invisible virus, or to the intervention of vectors of pathogenic agents, as the evidence of personal or environmental uncleanliness, then it may be said that the two chief causes of diseases are faulty food and dirt. These two are the senior partners in the criminal business of disease- production– each the coadjutor of the other.
It is along lines of improved cleanliness, both personal and environmental, that the triumphs of modern medicine have lain; it is along lines of improved nutrition that greater triumphs still remain to be achieved. Some years ago I made the statement that “the newer knowledge of nutrition is the greatest advance in medical science since the days of Lister.
When physicians, medical officers of health and the lay public learn to apply the principles which this newer knowledge has to impart . . . then will it do for medicine what asepsis has done for surgery.” I see no reason, in these later days, to detract from this view; on the contrary, there is every reason to emphasize it the more, particularly in regard to preventive medicine.
In this country the conviction that faulty food, and the faulty nutrition resulting from it, is a principal cause of ill-health, does not appear to be acquired so readily as it is in the Tropics. Perhaps it is that as an island race we have no others, at close range, with whom to compare ourselves.
The tribes of the Indian Frontier are far removed from the slums of our great cities; and it would be as difficult for the slum-dweller to realize the perfection of physique to which these tribes attain, though nourished on the simplest and least varied kinds of foods, as it would be for the Frontier tribesmen to understand that the physical imperfections of so many of the dwellers in the slums are largely due to the imperfections of the foods on which they are reared. Nevertheless, things nutritional are not, in essence, so different in India and in England as they may seem.
It is not only amongst the poorer classes in this country, but also amongst those who are better off, that the diet is commonly excessively rich in vitamin-poor, mineral-poor starchy foods and in protein-less, vitamin-less, minerally deficient sugar.
It is impossible for people subsisting on such diets to remain in good health. “It is only being gradually realized,” says Dr. Friend, whose recently published book, The Schoolboy, is so valuable a contribution to the problems of food and nutrition, “that the deficiency of white bread in vitamin B is one of the most serious dietary deficiencies to which our populations are being subjected at the present time”. To this I would add that incoordinate use of refined sugar is one of the most serious addictions of the day.
That the insufficient ingestion of vitamin B1 i an important and widespread cause of ill-health–especially of gastro-intestinal ill-health– is now recognized in America, where “the bread-meat- potato-sugar” diet of many American people has recently been shown to be dangerously low in this important factor, unless it is supplemented with a sufficiency of milk, eggs, fruits, nuts and vegetables (Sure, 1933).
And if in America, why not this country also, where the average diet is of the same “bread-meat- potato-sugar” sort ? You will remember that 10 per cent. of the rats fed on a diet such as is commonly used by the poorer classes in this country developed polyneuritis — a sure sign that it was deficient in this factor. According to American observers the mal-effects of such a diet are chiefly to be observed in children who exhibit poor appetites, poor growth, nervousness, constipation and other digestive disorders: effects which I observed, and recorded, in monkeys eighteen years ago.
NATIONAL ILL-HEALTH.
What evidence is there of physical inefficiency in this country? and what that such as may exist is related in its origin to faulty nutrition? For answer to the first of these questions I must turn to certain authoritative publications. From the first of these — the Report of the Adjuvant-General for the year 1934 — I quote the following passage: “What was disconcerting to any citizen with a care for the good of his country was that over 52 per cent. of the men who went to the recruiting office did not come up to the physical standard laid down. In the big industrial areas of the North the percentage of rejections rose to sixty- eight.”
The opinion of a high military medical authority was that the chief cause of the mens rejection was malnutrition during childhood. These figures are in themselves sufficiently disconcerting, but more so perhaps when it seems likely that the men who did present themselves for recruitment were not so physically impaired as many who did not. And if so high a percentage of men failed to come up to the by no means exacting physical standard laid down by the Army authorities, how many of their womenkind were likely to be physically inefficient?.
