Research has been focussed on many aspects of this disease and one of the aspects has been nutrition.

Diet

Diet is one of the vital factors essential for sustenance of life. However in as much as food is vital for maintenance of various biological processes within our body, it is even more vital to know that the type of food we select as a diet can turn out to be the cause of our death.

Diet could exert its effect on human cancers in a number of different ways

1. Through carcinogens produced by food processing or cooking
2. Through carcinogens in the body produced during digestion, especially in the stomach, small or large intestines
3. From food constituents itself
4. Through the indirect effects of undernutrition, malnutrition and overnutrition and
5. Through the protective effects of certain dietary factors.

The relationship of cancer with nutrition is one of the oldest known, but, perhaps one of the most neglected facts.

Let us study the relationship of cancer of various organs and diet.

Breast Cancer

Data collected from 24 countries has concluded that the best correlation between the diet and cancer is in the case of the breast. Several other international correlation studies have been conducted with similar conclusions.

Surveys on international incidence have shown that Asians and Africans have much lower incidence than Europeans and North Americans. Thus it is much more common in countries with a high level of affluence. It has been suggested that the over stimulation of the hormonal system by an 'affluent' diet might lead to growth of hormone dependent cancers such as carcinoma breast.

In Japan dietary fat has increased from per capita consumption of 23 to 52 gm per day between 1957 and 1973. In this period of time the annual breast cancer mortality rate increased from 1572 to 3262. In the U.S. where already there is a high incidence of cancer of the breast, the incidence has further increased because the per capita dietary consumption of fat per day has risen from 125 gms in 1909 to 186 gms in 1972.

Besides the relationship with high fat diet, mainly animal fat, breast cancer has also been associated with protein intake. Actually there has been a much stronger relationship between animal protein, rather than total protein and breast cancer.

In fact it has been shown that cancer patients on high fat diet have a poorer prognosis than low fat diet patients. This all probably explains the high incidence of breast cancer in U.S. women.

Similarly breast cancer has also been associated with nonvegetarian diets and obesity. These associations have been seen in several epidemiological surveys and has also been our experience at the Bombay Hospital.

Large Intestine Cancer

Surveys of the incidence of gastro-intestinal cancers suggest that as total per capita food intake (i.e. caloric intake) increases, the incidence of colorectal cancer increases.

It was further found that colorectal cancer has been frequently associated with the intake of animal protein. High intake of animal protein, particularly beef in Hawaii and pork in Japan have been clearly shown to be associated with a high incidence of cancer of the bowel.

Stomach Cancer

Certain data has shown that this cancer is very common amongst several fish eating communities particularly Japan, Iceland, Finland, Soviet Union (along the Baltic Sea) and South African Coast. Japan has a higher consumption of fish than that of the U. S. and has a five times higher incidence of the cancer of the stomach.

Prostatic Cancer

The association between dietary fat and prostatic carcinoma is seen in international comparison. Surveys conducted in U. S. by Blair and Fraumany identified the midwest and north central areas of the U. S. as those with the highest rate of prostatic carcinoma and this was related to the greatest consumption of beef.

Other organ cancers in the body, like testes and corpus uteri have all shown a relationship with dietary factors which point mainly to the animal component of diet as carcinogens.

The Rationale of Vegetarianism

As has been discussed in various chapters throughout this book, vegetarian diet seems to be the diet more suited to man. Hence when a person is on a vegetarian diet he receives most of his nutrition in the optimal form and hence keeps the body going without imposing a load on the elimination systems.

Consumption of a vegetarian diet particularly in the fresh and uncooked form supplies the body with all the carbohydrates, proteins, fats and especially the trace elements, vitamins, minerals, and other micronutrients. These go to enrich the internal environment and enhance the functioning of all the organs of the body wherein the body is able to cope with any kind of foreign invasion or any kind of derangement like malignant disease.

When a patient suffers a malignant disease he has probably no vitality or resistance to foreign invasion. A normal person is able to keep healthy inspite of such a diverse array of influences acting upon him because his immune system is competent and can quell any foreign invasion. In a patient suffering from cancer, the immune system is very weak due to chronic influences like poor nutrition, nutritional deficiencies (especially of micro nutrients), cigarette smoking, alcohol and tobacco abuse and mental stress, altogether or individually. This is the reason why the malignancy can flourish unchecked. However, if the patient is given nutrition which is natural to his system then gradually the deficiencies get corrected and the immune system gets rejuvenated. This assists in the fight against the disease process. And, it appears, that it is one of the causes of some patients responding very well to therapy and some not responding at all.

Vegetarian nutrition definitely imposes a smaller load on the elimination systems, it also contains all the nutrients in their natural concentrations and combinations whereby digestion, absorption and assimilation are done easily. Due to the high fibre content, poisonous waste matter is propelled rapidly down the colon and egested intermittently—hence it serves a cleansing function. Vegetarian food—particularly in its natural, uncooked form possesses all these properties of nourishing and cleansing the system.

It has also been established that eating of hypoealoric diets inhibit many tumours e.g. breast carcinoma, lung carcinoma, hepatoma, leukaemia, skin turnouts and sarcoma. This is possibly true due to the inhibition of mitotic activity due to limited carbohydrate and carbohydrate intermediates available for energy.

Below given are suggestions which may help to reduce your chances of getting cancer.

1. Salt-pickling, smoke-curing, nitrate curing and frying or boiled meat products should be avoided. (These preservative or cooking procedures are mainly used for animal food) Said Dr. William Lifinsky, a cancer researcher at Oak Ridge National Laboratory in Tennessee, "I wouldn't even feed nitrate laden foods to my cat...."
2. Dietary intake of fat to be reduced. A solution offered by simple vegetable food.
3. Protein consumption in the form of non-veg. food should be substituted by vegetable protein. Nutritional experts say that a combination of pulses in the diet provides adequate proteins of high biological value with all essential aminoacids and in a much more assimilable form. Thus the common excuse for consuming non-veg. diet as a rich source of protein is a myth, not backed up by any scientific observation.
4. Additives, flavours and colouring agents e.g. nitric acid in red meat can be hazardous. In general, it is best to forego a preference for these.
5. Consumption of fibre diet should be increased e.g. the present U.S. diet fibre intake averages to 20 gm per day. However the recommended is average 60 gms per day for human bemgs.
6. Certain vegetables have a protective action against cancer, quite separate from their fibre and vitamin content. These are cruciferous vegetables mainly cabbages, cauliflower, brocoli, brussel sprouts, kohlrabi etc. They should be eaten frequently.
7. Dark green and yellow leafy vegetables and fruits have protective value and should resnl rlv fissure in the diet. Besides dietary habits, alcohol, smoking, tea and coffee should be avoided.

Table below depicts a list of mutagens present in food, both vegetarian and non-vegetarian. The elimination of non-vegetarian food from the diet reduces the load of mutagens significantly hence placing the consumer at a lower risk level.

Presently it is established that simply by applying the knowledge we have now, we could reduce the occurrence of new cancer cases by upto 40% but we are kept from realising this potential because of certain deficiencies, at the level of the individual and the society.

It is clear that diet acts as a double edged razor. While right selection can promote health and well being a faulty choice of our diet can jeopardise our health. Unfortunately, there is a lack of organised and systematically collected data to show us the true status of cancer in our country. It may not te very long judging by the present rate of adopting the westernised life style, before India lands up high on the list of countries with major cancer deaths.

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