Is cancer A Preventive Disease?

Is cancer A Preventive Disease?
Amr Mattar
Prof. of Anesthesia and President of
Egyptian Society of Parentral and Enteral Nutrition
Are we facing a CANCER EPIDEMIC as according to IARC updates cancer cases are increasing tremendously, doubled from 1975- 2000 expected to double again on reaching 2020 and even more to be in 2030 Then the question will be how can we stop that malicious disease? Is Cancer a preventable disease? According to WCRF/AICR (1streport): Cancer is principally caused by environmental factors ;( tobacco, diet, factors related to diet including BMI & physical activity and workplace exposures).40% of all cancers are linked to poor diet, physical inactivity & excess BW.30% of all cancer deaths are linked to smoking. *Thus Reorientation of public health priorities*Reduced exposure to risk factors & promotion of healthy lifestyles are important measures in cancer prevention. This was confirmed in WCRF/AIRC (2nd expert report)2007:The essential role of food, nutrition & body composition in cancer initiation,promotion & progression. The most famous nutritive element in prevention of cancer GIT, Upper Aereodigestive Cancer mouth, pharynx, esophagus, stomach,larynx. Five or more servings/ day “of Non starchy vegetables & fruits” are national recommendations for protective effect. Below which cancer risk isincreased GIT, Stomach Cancer: Excessive salt and Na intake. May damage lining of stomach,increase carcinogen activity, may facilitate H pylori infection.Therefore WCRF recommends to: “Limit salt intake to 2.5 gram/d consider all dietary sources”GIT, Colorectal Cancer • Dietary fibre: may protect against colorectal cancer through binding to carcinogens • Alteration of gut environment (lowering fecal pH, stimulation of bacterial fermentation & production of short chain FA espbutyrate which regulate cell cycles). “So eat more of unrefined cereals, legumes, vegetables,fruits” • “Colorectal cancer is related to the way of cooking & preserving meat, rather than meat itself. Cooking meat at high temperatures (frying, grilling, barbecuing) Processed meat: preserved by, smoking, salting or preservatives. Processed meat may contain nitrates & nitrites. Nitrates (NO3) are essentially non-toxic but can be reduced to nitrites(NO2) in improperly stored food or in thebody Milk, dietary calcium (from dairy, nuts, pulses, fish)protects from colorectal cancer”. Cancer prostate: High dietary intake of calcium is apossible cause of cancer prostate. Liver Cancer: Foods contaminated with Aflatoxins (a type of carcinogens) are a causeof liver cancer. • Aflatoxins mainly present in cereals, legumes esp. peanuts, nuts, seeds, due to damp climate & poor storage conditions, Aflatoxins are converted to carcinogenic form by cytochrome P-450, interacting with cellular DNA &patients. • Genetic polymorphisms in (GST), regulate metabolism of aflatoxins

& are factors of individual’s susceptibility to Aflatoxin-inducedhepatocarcinogenesis. Lung cancer Risk reduction isrelated to: Fruit consumption (in smokers & non- smokers).High vegetable intake (smokers).ex: apples, pears,citrus fruit, cruciferous vegetables. as well as Selenium Supplements: •While lung cancer riskincreases with high dose of beta- carotene, and exposure to water contaminated with inorganicarsenic. Breast Cancer Diets high in fats (esp. saturated fat) may be a causeof postmenopausal breast cancer Overweight & obesity: A cause of cancer of colorectum, breast, endometrium, esophagus, pancreas & kidney. This is may be due to- Increased inflammatory response. - Increased estrogen synthesis,insulin output. - Accumulation of environmentalchemical carcinogens. Overeating may represent the most imp. avoidable cause of cancer innon-smokers.Phytochemicals: Compounds with documentedchemo preventive properties. • Confer particular properties onfoods (taste & color).
• Possess anti-oxidant, anti- carcinogenic, anti-inflammatory, immune modulant & antimicrobial effects Family of compounds as, beta- carotene, lycopene, like Carrots, apricot, peaches, cantaloupe, sweet potatoes spinach, broccoli. They act as antioxidants (lycopene) & immune-enhancers. Protecting against aerodigestive,lung & prostate cancer.Isothiocyanates: Sulphur-containing phytochemicals., responsible fortypical vegetable flavor. Its anti-cancer properties by Inhibiting cell proliferation, inducing apoptosis ,inducers of liver enzymes for carcinogendetoxification Cruciferous vegetables (broccoli, cauliflowers) reduce risk ofprostate cancer. Possible protective role against gastric, colorectal, ovarian &bladder cancerFlavonoids: Compounds found in plants (stem, leaves, fruit peel) & responsible for pigmentation .e.g. quercetin,exert immmunomodulatory, anti- inflammatory, antioxidant activity, Antioxidant activity enhanced byvit. CVitamin D: The Sources: Exposure to UV
radiation, present in cod liver oil, salmon, tuna, mackerel, sardines,fortified milk, eggs.The Protective effects of Vit D : - Regulates cell growth, differentiation, apoptosis, regulateimmune function. So in Summary the 2nd expert report recommendations states that :- BMI: 21-23• Moderate exercise. • Increase intake of vegetables &fruits at least 5/d. • Increase intake of whole cereals &legumes. • Limit energy-dense foods, refinedCHO, alcohol.•Avoid sugary beverages. •Consume fast foods sparingly, ifat all; •Limit intake of salty & Na-processed foods to