This, too, is the experience of stock- breeders. Is man an exception to a rule so universally applicable to the higher animals? It seems most unlikely that he can be, although it is to be recognized that his requirements for adequate nutrition, and the effects upon him of deficiencies of various food-essentials, are not necessarily the same as in animals. Indeed, these effects are known to differ in different species of animals.
Nevertheless, the principles of nutrition are fundamentally the same in man and in animals. It may, therefore, be taken as a law of life, infringement of which will surely bring its own penalties, that the greatest single factor in the acquisition and maintenance of good health is perfectly constituted food.
FOOD AND PHYSICAL EFFICIENCY.
Nowhere in the world is the profound effect of food on physical efficiency more strikingly exemplified than in India. As you know, India has some 350 million inhabitants, made up of many races presenting great diversity in their characteristics, manner of life, customs, religion, food and food-habits.
The tribes of the Indian Frontier, and of Himalayan regions, the Peoples of the Plains – Sikhs, Rajputs, Mahrattas, Bengalis, Ooriyas, Madrassis, Kanarese and many others – exhibit, in general, the greatest diversity of physique. And as each race is wedded to its own manner of living, to its own national diet, comparison between them is easy.
The level of physical efficiency of Indian races is, above all else, a matter of food. No other single factor – race, climate, endemic disease, etc. – has so profound an influence on their physique, and on their capacity to sustain arduous labour and prolonged muscular exertion. “As we pass form the North-West region of the Punjab down the Gangetic Plain to the Coast of Bengal, there is a gradual fall in the stature, body-weight, stamina and efficiency of the people.
In accordance with this decline in manly characteristics it is of the utmost significance that there is an accompanying gradual fall in the nutritive value of the dietaries.” So wrote McCay, as a result of his investigations, a quarter of a century ago. My own observations have served to confirm his conclusions.
FREEDOM OF WELL-FED ANIMALS FROM DISEASE.
So impressed was I by the adequacy of the northern Indians diet that during the later years of my experimental work I used it as the stock diet of my rats. Their food consisted of chapattis lightly smeared with fresh butter, sprouted Bengal gram (pulse), raw fresh vegetables (cabbage and carrots) ad libitum, milk, the hard crusts of bread (to keep their teeth in order), a small ration of meat with bone once a week, and water. The average daily strength of the stock rats so fed about 1,000.
They were kept in stock for about two years – a period approximately equal to the first fifty years in the life of a human being – the young being taken as required for experimental purposes, and the remainder used for breeding. During the five years prior to my leaving India there was in this stock no case of illness, no death from natural causes, no maternal mortality, no infantile mortality.
It is true that the hygienic conditions under which they lived were ideal, that they were comfortably bedded in clean straw, that they enjoyed daily exposures to the sun practically the whole year round, and that the care bestowed upon them was great; but the same care was bestowed during these years on several thousand deficiently-fed rats, which developed a wide variety of ailments while the well-fed animals enjoyed a remarkable freedom from disease.
It is clear, therefore, that it was to their food that this freedom was due. If man himself did not provide in his own person the proof that a diet composed of whole cereal grains, or a mixture of cereal grains, milk, milk- products, pulses and vegetables, with meat occasionally, sufficed for optimum physical efficiency, this experience in rats would do so.
It is not, therefore unreasonable to conclude that if by minute attention to three things – cleanliness, comfort and food – it is possible to exclude disease from a colony of cloistered rats, it is possibly greatly to reduce its incidence by the same means in human beings and to produce a race whose physique is as nearly perfect as nature intended it to be.
Supposing now we cut out the milk component of this diet or reduce it to a minimum, we find that disease soon begins to make its appearance, especially if at the same time we limit the consumption of fresh vegetable foods. I have repeatedly made these restrictions with the result that respiratory diseases, gastro-intestinal diseases and maladies consequent on degenerative changes in mucous membranes and other structures of the body become frequent.
It is apparent, therefore, that the diet of the Sikhs is only health-promoting so long as it is consumed in its entirety. Indeed, we know that those of this race who, for whatever reason, do not consume adequate quantities of milk, milk products and fresh vegetables, do not long retain the fine physique for which the Sikhs are famous.
These food- materials are for them and in their own parlance, takatwar khurak (foods that give strength) which we now-a-days speak of as “the protective foods”, since they make good the deficiencies of muscle meat, refined cereals, etc., which enter so largely into the diets of western peoples.
Before leaving this experience, let me emphasize two things: the first, that all things needful for adequate nourishment of the body and for physical efficiency are present in whole cereal grains, milk, milk-products, legumes, root and leafy vegetables and fruits, with egg or meat occasionally. What is eaten besides these is a more a matter of taste than of necessity.