A comprehensive study made by National Cancer Institute, U.S.A. (NCI)estimated that 35% of all cancers, particularly in the United States, can be associated with dietary incluences. The main factor increasing colon cancer risk was too much dietary fat and too little dietary fibre.
Most Americans get 40 percent of their total calories intake from fat. The level generally recommended for prevention of cancer and heart diseases is 30% or less of calories from fat. NCI recommends dietary guidelines that include cutting fat consumption by eating low fat diary products, fish and lean meat and increasing intake of fibre as in fresh fruits and vegetables containing Vit. A, Vit. C. and Beta-carotene found in green and yellow vegetables and converted to Vit. A in Digestive tract.
Fibre in diet increases the bulk of stool and speech of transit. Transit time is the length of time food takes to pass through the body. In western diet it may take 48 to 72 hours. Among the poor and tribals eating unrefined food this takes a short six hours. While officers in British navy and their wives had stool which ranged in weight from 38 to 223gms. (two table spoon to a cup in volume).
British vegetarians like vegetarians from Uganda and India has stool weighting from 178 to 980 gms, the average being four times that of naval officers. Bulky stool dilute carcinogens present in stool and rapid transit reduces time of action for the carcinogens on the gut wall. Thus fibre in diet help us in prevention against cancer.
Exposure of meat to high temperature as in charcoal and microwave oven help in the formation of a compound with more carcinogenic risk. Nitrates used in the preservation of meat are carcinogenic in the stomach and oesophagus. Vit. C inhibits their effect. Increased use of Vit C may account in part for the decrease in the incidence of gastric carcinoma observed in recent years.
Large amount of nitrates in certain vegetables, overfertizied, are carcinogenic to some extent. Better to fertilize the fields with organic matter and use minimum insecticides to prevent this problem. Aflatoxin has been linked strongly to hepato cellular carcinoma in Africa and Asia. Aflatoxin is found in peanuts and grains stored under moist conditions.
There is lot of fadism regarding diet. Big industries promoting different food products. They claim them to be wholistic and will give you energy and vitality, make you more attractive and reverse the process of disease. How far they true? They invent every day indigenous methods to defraud the masses.
The food industry is concerned with gratifying the taste buds and making profits than looking after their customer’s health. Fast food joint are opening up in major towns in India. They provide pizzas, hamburger, ice creams and milk shakes. These are high calorie foods loaded with lots of fat and sugar and lacking in fibres. These are junk foods.
Cancer can be brought down with right diet. Vit. C, Vit. A, carotene are protective against cancer. So are cabbage cauliflower which have a chemical in them called indole which acts against the cancer in the bowel. The fibre plays a great role. It protects us against many diseases from constipation to heart diseases and cancer.
There are two main groups of fibre rich food. Cereal food made from whole grains, whole wheat flour, brown rice, bran based biscuits and crackers. The other type is found in indigestible cellulose – the roughage of fruits and vegetables. Fruits and their skin, potatoes, green leaves, spinach, cabbage and cauliflower are important for our diet. You can take peas, beans, lentils. They contain proteins and fibre.
The fibre from cereals in an inferior fibre source. The fibre in fruits, vegetables and pulses are softer type and superior. Wheat fibre has no effect on the cholesterol level. The viscous type fibre present in fruits and vegetables in large doses produce a major reduction in cholesterol. Artificial sweeteners, saccharin and cyclamates, are associated with cancer of bladder. Cooking practices like too much frying or too much browning of onions and masala may release hydrocarbons or other carcinogens in food although no epidemiological observations are available.
Colon and rectal cancer is more common in developed countries. Its incidence is high in north America, New Zealand, Europe and low in South America, Africa and Asia. The United Stated has the highest rate of colonic cancer in the world. There is a high risk among the city folk than the rural population. Diet is an important factor. There is low incidence of appendicitis, adenoids (tonsilitis), diverticulosis, ulcerative collitis, and colorectal cancer in South Africa, Bantu area, where the diet contains more fibre and less animal fat.
There is direct association between fat and animal protein intake in the western diet and the rising incidence of colonic cancer. In Japan, the intake of fat (mostly unsaturated) provide only 12% of total calorie intake. In the United States the fat intake represents 40-44% of the total calories intake.