DIET AND CANCER By Chika Ndiokwelu. Ph.D Department of Nutrition and Dietetics, UNTH, Ituku-Ozalla.

Introduction Diet and Cancer Risk: Over the past three decades, considerable attention has been given to potential role of dietary factors in the cause and prevention of cancer. Evidence of link from animal and epidemiological studies. Estimation from various epidemiological factors shows that 35% of cancer deaths may be related to diet. No conclusive evidence that a specific diet or nutrient on its own causes or prevents cancer in humans. Scientists believe it is due to interplay of genetics &various envirenmental factors of which diet is one.

Dietary Guidelines to Reduce Risk of Cancer Maintain desirable weight. (Association b/w breast, uterus, colon, gallbladder, body weight and prostrate. degree of obesity) Eat a varied diet but in moderation.( B/c, maybe difficult to seperate effects of fibre from confounding effects of energy and other nutrients). Offers the best hope for lowering cancer risk Include a variety of both and fruits vegetables in the diet.(Associated with in risk of lung,prostrate, bladder, esophageal, and stomach cancers.)

Dietary Guidelines to Reduce Risk of Cancer Eat more fibre high foods, such as whole grain cereals, legumes vegetables, and fruits.(hypothesis- diet dilutes the carcinogens in the colon by reducing their contact time through more rapid transit/reducing their formation by altering the bacterial flora/ high fibre diet of grains, fruits, &vegetables may be acting indirectly by replacing high calorie high fat foods.(fibre, provitamin A, phytochemical elements)

Dietary Guidelines to Reduce Risk of Cancer Cut down on total fat intake to 30% or less of total caloric intake ( fat intake increases risk of breast, colon and prostrate cancers) Limit consumption of alcoholic beverages if you drink at all. (Heavy drinkers have increased risk for various cancers- oral cavity, larynx and esophagus.This risk is magnified in cigarette smokers.Alcohol has been implicated in development of liver,pancreas, colon and most recently, breast cancers. However, these relationships have not yet been established )

Limit consumption of salt-cured and nitrite- prevserved foods. Limited inferential evidence that salt-cured, pickled and nitrite-cured foods( sausages, bacon) may risk of stomach and esophageal cancers in countries where these foods are eaten commonly. **These recommendations are designed for adults in good health& not to be applied indiscriminately to children,pregnant women, convalescencents or the elderly. These group may have special nutritional needs that may need special supervision by physicians.

Other Dietary Constituents Those under investigation include: Food additives. Probablly make, at most,a small contribution to cancer risk. Caffeine. Evidence still inconclusive.Implicated in some studies but not in some.No indication that it is a risk factor in human cancer. No recommendation against its moderate use. Artificial sweetners. Consequencies of long term use especially in children and pregnant women cannot be predicted. Long -term effects of use of aspartame is still being studied.

Other Dietary Constituents Methods of food preparation: Broiling and grilling of meat at very high temperatures, eg charcoal grills, may result in formation of carcinogenens. Still under active investigation. Very hot foods and beverages and food broilled/grilled at very hot temperature, meat fried a very high temperature, should be avoided to reduce cancer risk. *Alcohol beverages, coffee, and tobacco, when thes are combined potentiate their carcinogenic effects.

Foods In The Prevention of Cancer Foods play a vatal role in cancer prevention. However, when it has been diagnosed, diet continues to be of vital importance. Anticarcinogenic components of Foods. Fruits: Citrus,Combined effects of, flavonoids, limonoidspectin&vitamin C- guavas Grapes-resveratol particularly on the skin

Foods In The Prevention of Cancer Olive oil - rich in antioxidants. Studies have shown that when substituted for other dietary fats, it breast cancer risk. Whole grains - besides fibre, contains phytates which act as antcarcinogens. Vegetables – provitamin A,vitamin C, antioxidant phytochemicals. Most effective – carrots.tomatoes,sweet peppers,eggplants,onions’garlic (flavonoids inhibit tumour growth),cabbage,brocolli,radishes

Foods In The Prevention of Cancer Natural Yoghurt ( active bacterial cultures&lactic acid). Legumes –fibre, phytic acid,phytate. Soy & its deratives e.g soymilk (isoflavones – genistein,daidzein. These are plant hormones phtoestroges that avoid undesirable effects of estrogen eg promotion of cancer. It has been shown to be particularly effective against breast cancers.

General Food-based DietaryGuidelines Increase intake of : Fruits,green leafy vegs,vegetable oils,garlic and onions,whole grain bread,soy,fermented dairy produts-natural yoghurt,olive oil,nuts,fresh veg salads,citrus,fresh tomatoes- lycopenes,fish.

General Food-based DietaryGuidelines Reduce or eliminate intake of: Meat,animal fat,pork lamb,sugar,coffee,fried foods,excess calories,full cream milk,sodium(salt),wine,beer&other alcoholic beverages,eggs,cured or salted fish,chocolate &pastries, for breast cancer magarine &commercial baked foods- trans fatty acids