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HEALING FOODS PHYTOCHEMICALS Foods for Cancer Prevention Focus on Vegetables & Fruits with “BIG Color & BIG Flavor” Vicky Newman, MS, RD Associate Clinical Professor UCSD School of Medicine
Diet and Cancer Current Associations • • • Breast Prostate Colon Pancreas Lung Bladder Ovary/cervix Gastric Oral/esophagus
POSSIBLE WAYS DIETARY CONSTITUENTS PROTECT AGAINST CANCER • Antioxidant effects • Effects on cell differentiation • Increased activity of enzymes that detoxify carcinogens • Blocked formation of nitrosamines • Altered estrogen metabolism
POSSIBLE WAYS DIETARY CONSTITUENTS PROTECT AGAINST CANCER • Altered colonic milieu (including bacterial flora, bile acid composition, p. H, fecal bulk) • Preserved integrity of intracellular matrixes • Maintenance of normal DNA repair • Increased destruction of cancer cells (apoptosis) • Decreased cell proliferation
PHYTOCHEMICALS (Plant Protectors) • Substances produced by plants to protect them from damage from environment (predators, pathogens, solar radiation). • Antioxidants. • Include toxins produced by plant to fight off predators. When eaten by humans, these upregulate detoxifying enzymes that help protect from harmful substances, including carcinogens. • Considered non-nutritive, because they do not provide energy, vitamins, or minerals. • Most are heat stable and not significantly lost in cooking water.
Increase Proportion Who CONSUME > 3 DAILY SERVINGS VEGETABLES • Healthy People 2010 Target • All age groups* 75% 49% • • • 43% 49% 43% 68% 64% 56% Female 20 -39 years* Female 40 -59 years* Female 60+ years* Male 20 -39 years* Male 40 -59 years* Male 60+ years* *CSFII (2 -day average), 1994 -96.
Increase Proportion Who CONSUME > 1 DAILY SERVING DARK GREEN/DEEP YELLOW VEGETABLES • Healthy People 2010 Target • All age groups* 75% 8% • • • 9% 11% 13% 4% 9% 11% Female 20 -39 years* Female 40 -59 years* Female 60+ years* Male 20 -39 years* Male 40 -59 years* Male 60+ years* * CSFII (2 -day average), 1994 -96.
Increase Proportion Who CONSUME > 2 DAILY SERVINGS FRUIT • Healthy People 2010 Target 75% • All age groups* 28% • • • 20% 26% 35% 23% 28% 40% Female 20 -39 years* Female 40 -59 years* Female 60+ years* Male 20 -39 years* Male 40 -59 years* Male 60+ years* * CSFII (2 -day average), 1994 -96.
Nine are Divine
Go for the BOLD BIG COLOR • Pigments give color to food and thus enhance eating enjoyment. • Almost 2, 000 known plant pigments in our food, including over: - 800 flavonoids (yellow) - 450 carotenoids (orange, red) - 150 anthocyanins (blue, purple). • These pigments help protect us from disease.
CAROTENOIDS • Powerful antioxidants • Some metabolized to vitamin A (retinol): - stimulate immune function; - role in differentiation of normal epithelial cells; - may further inhibit cell proliferation; - may induce increased cellto-cell communication.
DARK-GREEN LEAFY VEGETABLES • Contain carotenoid lutein: - no vitamin A activity, but antioxidant activity; - protective against macular degeneration. • Rich in folic acid: - deficiency may lead to chromosomal damage (cells less resistant to viral damage; also necessary for DNA repair).
LYCOPENE • Responsible for the red color of tomatoes, also found in tomato juice, sauce, pink grapefruit, salsa • The predominant carotenoid in plasma; age and BMI inversely assoc with lycopene concentrations • Inverse relationship with prostate cancer (RR 0. 65, CI =0. 42 -0. 99) & cancers of GI tract • Evidence in breast cancer less substantial with RR of approx. 0. 8 -1. 02. Giovanucci E. JNCI , 2002; Giovanucci E. JNCI, 1995; La Vecchia C. PSEBM, 1998; Ching, J Nutr 2002.
TOMOTOES vs LYCOPENE • Study supports “whole is greater than sum of its parts”…or food more effective than an isolated food component. • Tomato powder but not lycopene supplement inhibited prostate cancer in rats. Boileau TW-M, JNCI 2003; 95: 1578 -86; Gann PH, JNCI 2003; 95: 1563 -65).
BERRIES, RED GRAPES, RED CABBAGE Contain significant levels of phenolic flavonoids (like ellagic acid, ferulic acid): • Act as antioxidants; • Protect against LDL oxidation; • Inhibit platelet aggregation.
ANTHOCYANINS (red & blue pigments) • • Antioxidant flavonoids. Anti-inflammatory. Relax blood vessels. Inhibit cholesterol production. • Inhibit activity of enzyme that speeds cell division (potentially decreasing cancer risk). • May protect against memory loss (aging).
Go for the BOLD BIG Flavor
CITRUS FRUIT (coumarins, D-limonene, glucarates) • Contain coumarins & D-limonene, a terpenoid shown to increase activity of detoxification enzyme (glutathione transferase). • Citrus pulp & white inner peel rich in glucarates (potential to prevent breast cancer & lower PMS symptoms).
CITRUS FRUIT (Rich in Vitamin C) • Fights infection. • Antihistamine effects. • Antioxidant (protects cell membranes & DNA from oxidative damage). • Decreases conversion of nitrate to nitrite (reducing formation of nitrosamines). • Necessary for synthesis of collagen (deficiency could affect integrity of inter- cellular matrixes allowing tumor growth or hindering tumor encapsulation).
CITRUS FRUIT (Rich in Flavonoids) • Extend activity of vitamin C. • Antioxidants. • Protect LDL cholesterol from oxidation to unsafe cholesterol oxides. • Inhibit platelet aggregation (decreasing blood clotting) • Anti-inflammatory & antitumor action. • Bioflavonoids in plants thought to act as insect attractants, repellants, & anti-fungal agents.
CRUCERIFEROUS VEGETABLES • Arugula, Watercress • Broccoli • Brussels Sprouts • Cabbage • Cauliflower • Greens (Collard, Mustard) • Kohlrabi • Kale • Radishes • Rutabaga • Turnips
CRUCIFEROUS VEGETABLES • Rich in sulfur compounds (sulphorophane & other isothiocyanates) that increase activity of enzymes involved in detoxification of carcinogens. • Contain indole-3 -carbinol: - increases inactivation & removal of estrogen; - favors production of estrogen that is essentially inactive biologically.
The Anticarcinogenic Mechanisms of Isothiocyanates (ITCs) Procarcinogens Ultimate Carcinogens DNA Damage Inhibit carcinogenactivating enzymes e. g. , P 450 s Induce carcinogendetoxifying enzymes e. g. , GST Induce apoptosis & cell cycle arrest Inhibit inflammation Cancer ITCs
ALLIUM VEGETABLES Onions, garlic, scallions, leeks, chives Contain protective sulfur compounds (allyl sulfides): • Enhance enzymatic detoxification systems; • Antibacterial activity may serve to inhibit bacterial conversion of nitrate to nitrite in stomach (reducing formation of nitrosamines).
Allium Vegetables, Derivatives & Breast Cancer • Inhibition in growth of ER+ and ERbreast cancer cell lines • Epidemiological evidence: reduced incidence of breast cancer assoc. with allium vegetable consumption, but not garlic supplement (Dorant et al. , Brst Ca Res and Treatment, 1995).
AROMATIC HERBS • Basil, marjoram, mint, oregano, rosemary, sage, savory, & thyme contain potent antioxidants (some possess anti-tumor activity. • Terpenoids, compounds responsible for flavors of many common herbs & seasonings, also useful in cancer chemoprevention.
PLANT PHENOLICS Cancer Prevention Agents • Found in fruits, vegetables, grains. • Average consumption 1 -2 g/day. • Functions in plants: - Antioxidant - Antiviral agents - Color - Structural (used to produce lignins)
ANTI-CARCINOGENIC PROPERTIES • Antioxidants • Inhibit production of cancer-causing nitrosamines • Inhibit chemical mutagens (protect DNA) • Modulate inflammatory response (arachidonic metabolism)--decreases growth/spread of cancer cells
HIGHEST IN PHENOLICS 10 Commonly Consumed Vegetables (Chu YF. J Agric Food Chem 2002 (Nov 6); 50(23): 6910 -6). • • • Broccoli (highest) Spinach Onion (yellow) Pepper (red) Carrot • • • Cabbage Potato Lettuce Celery Cucumber (lowest)
HIGHEST TOTAL ANTIOXIDANT ACTIVITY 10 Commonly Consumed Vegetables (Chu YF. J Agric Food Chem 2002 (Nov 6); 50(23): 6910 -6). • Pepper (red) (highest) • Broccoli • Carrot • Spinach • Cabbage • • • Onion (yellow) Celery Potato Lettuce Cucumber (lowest)
HIGHEST INHIBITORY EFFECT ON CANCER CELLS (Chu YF. J Agric Food Chem 2002 (Nov 6); 50(23): 6910 -6). • Spinach • Cabbage • Pepper (red) • Onion (yellow) • Broccoli
ANTIOXIDANT - RICH FRUITS Ranked by ORAC Units/1/2 cup serving (adapted from Nutr & MD, 8/99) • • • Prunes, dried Blueberries, fresh Blackberries, fresh Strawberries, fresh • Raisins, dried • Oranges, fresh • Plums, fresh Raspberries, fresh Grapes, red, fresh • Cherries, fresh
ANTIOXIDANT- RICH VEGETABLES Ranked by ORAC Units/1/2 cup serving (adapted from Nutr & MD, 8/99) • Kale, cooked, fresh • Brussels sprouts, cooked, fresh • Beets, cooked, fresh • Peppers, red bell, raw • Onions, cooked • Broccoli florets, cooked, fresh • Spinach, raw • Corn, cooked, frozen, kernels • Alfalfa sprouts, raw • Eggplant, cooked, fresh
Pesticide Risk HANDLE WITH CARE (Environmental Working Group - www. ewg. org) • Strawberries • Bell peppers (green & red) • Spinach • Cherries (US) • Peaches • Cucumbers • Cantaloupe (Mexican) • Celery • Apples • Apricots • Green beans • Grapes (Chilean)
Pesticide Risk SAFE BETS (Environmental Working Group - www. ewg. org) • • Avocados Corn Onions Cauliflower Sweet potatoes Brussels sprouts Cabbage • • Broccoli Green peas Carrots Bananas Grapes (US) Kiwifruit Plums
FIBER-RICH FOODS (Vegetables, Fruits, Whole Grains, Beans) • Rich sources of protective nutrients & phytochemicals. • Feel full with fewer calories (lowers risk obesity & hormone-related cancers). • Fiber speeds transit through GI tract (reducing exposure of GI mucosa to cancer-causing chemicals). • Fiber enhances excretion of carcinogens & excess hormones. • Bound phenolics released in colon to provide antioxidant protection.
PHYTIC ACID in Cancer Prevention • Phytic acid found in whole grain, beans, nuts, & seeds. • Also known as inositol hexaphosphate or IP 6. • In laboratory studies: - Ability to halt abnormal cell proliferation & shrink tumors; - Reduce angiogenesis (creation of new blood vessels that promote tumor growth).
WHOLE GRAINS (Adom KK. J Agric Food Chem 2002; 50(21): 6182 -7). • Antioxidant phytochemicals (phenolic compounds, especially ferulic acid) • Vitamin E (especially gamma tocopherol) • Folate • Fiber
INCREASE PROPORTION WHO CONSUME > 3 DAILY SERVINGS WHOLE GRAIN PRODUCTS • Healthy People 2010 Target 50% • • 7% 5% 5% 6% 11% 10% 12% All age groups* Female 20 -39 years* Female 40 -59 years* Female 60+ years* Male 20 -39 years* Male 40 -59 years* Male 60+ years* * CSFII (2 -day average), 1994 -96.
BEANS • Protease inhibitors may increase accuracy of DNA repair, decrease rate of tumor cell division, or decrease destruction of surrounding tissue. • Saponins may exert a preventive effect against colon cancer by binding bile acids & cholesterol in colon. • Rich in fiber (hastens movement of potentially irritating substances through intestines).
BEANS • Significant inverse relationship between frequency of legume intake & colon cancer incidence: Individuals consuming legumes >2 times/week were 47% less likely to develop colon cancer than individuals who consumed legumes <once/week. • Inverse relationship between non-soy legume consumption & prostate cancer. • Data from 41 countries revealed that countries with greatest consumption of had lowest death rates due to breast, prostate, & colon cancer. • One mechanism may be regulation of blood glucose and insulin (insulin-like growth factor).
SOYBEANS (Isoflavones) • Weak phytoestrogens (compete with more potent estrogens for binding sites). • Genistein inhibits activity of enzyme involved in growth of transformed cells. • Genistein & biochanin A increase destruction of tumor cells.
Best Sources of PHYTOESTROGENS Food Serving Soybeans, green ½ cup Daidzein & Genestein (mg) 117 Soybean sprouts ½ cup 48 Miso paste ¼ cup 89 Soy nuts ¼ cup 65 Tofu ½ cup 31
FLAXSEEDS • Rich in alpha-linolenic (omega-3 fatty acid)-anti-inflammatory. • Flaxseed meal rich in lignans (content is 75800 times that of 66 other plant foods). • Lignans act as estrogen antagonists (may decrease risk of hormone-related cancers).
LESS IS MORE Correlated with Less Fat in Diet • More vegetables • More fruit • More fiber • More carotenoids • More folate • More vitamins • More lowfat milk Subar AM. Am J Pub Health 1994; 84: 359 -66.
Tea and Breast Cancer • Breast cell line growth inhibition; apoptosis • Reduced tumor size and multiplicity in mouse model of mammary tumor • Consumption assoc. w/ reduced axillary lymph node metastases in post-menopausal women (Fujiki H, J Ca Res Clin Oncol, 1999). • Case-control study (Asian women in Los Angeles) found risk of breast cancer not related to black tea consumption, but 47% reduction in risk with 3 cups green tea/day (Wu AH. Int J Cancer 2003; 106(4): 574 -9.
Dietary Recommendations • Choose predominantly a plant-based diet. • Maintain a healthy weight & avoid weight gain in adulthood (<11 pounds) • Maintain physical activity (1 hr/day moderate activity & 1 hr/wk vigorous activity) • Increase vegetables (3 -5 svg/day) • Increase fruits (2 -4 svg/day) • Increase whole grains & legumes (3+/day) • Limit red meat (< 3 oz/day) • Limit dietary fat (15 -30% energy) • Limit alcoholic beverages (<1/day for women) • Limit charcoaled or smoked foods
UCSD HEALTHY EATING PROGRAM Sponsored by The American Cancer Society 619 -682 -7431