Cancer Flashcards
mechanism of cancer - Stage 1
Initiation - gene mutation of cellar DNA due to chemicals, radiation, virus - cell remains dormant for variable period until activated by promoting agent
mechanism of cancer - Stage 2
Promotion - initiated cells multiply (rapidly) to form a tumor
mechanism of cancer - Stage 3
Progression - cells multiply uncontrollably - invade surrounding tissue and metastasize
Dietary and cancer prevention - generally
vegetables, fruits, dietary fiber, certain nutrients seem to be protective against cancer. Fat, excessive calories and alcohol seem to increase cancer risk.
Energy balance and cancer
- caloric restriction with high nutrient density decreases risk
- obesity increases risk (due to more estrogen, insulin-derived growth factor)
ETOH and cancer
- linked to breast, colorectal, liver and pancreatic cancer
- 25% increased risk with 2 drinks daily (studies - men - colon cancer)
- x7 increase with inadequate intake of folate and methionine for distal colon)
Pickled/smoked foods, salt and cancer
- pickled and smoked foods are related to cancer of esophagus and stomach
- large amounts of food preserved by pickling and salting may increase cancer of stomach, nose, throat
Cooking methods and cancer
- frying and charcoal broiling meats at high temps create carcinogenic chemicals
- increased risk of stomach and esophageal cancers
- marinating meat before cooking may counteract risk
Fat and cancer
- total animal fat intake may increase postmenopausal breast, colon/rectal and prostate cancers
- linoleic acid (an omega-6) may increase prostate cancer risk
- saturated fat and omega-6 have been correlated with increased breast cancer risk
- PUFAs and oleic acid (MUFA) inversely associated with breast cancer risk
- olive oil appears to reduce breast cancer risk
- omega -3 hypothesized to be protective against breast cancer
Protein and cancer
- link between processed red meat (nitrates) and cancer
- low protein diets assoc with reduced cancer risk; diets with 2-3x RDA associated with increased risk
- controversial
Nitrates
- dietary nitrates are found in vegetables and drinking water, plus processed foods
- nitrates can be readily reduced to nitrites, which interact with amines and amides to produce nitrosamines and nitrosamides
- nitrosamines are potent carcinogens
Fruits/vegetables and cancer
- evidence is strongest for alimentary and respiratory tract cancers (colon, lung, esophagus, oral cavity)
- evidence weakest for hormone-related cancers (breast, ovary, cervix, endometrium, prostate)
- low intake increases risk by 2x for most cancers
Fiber and cancer
- conflicting results
- may reduce colon cancer (epidemiological)
- may reduce breast cancer - reduces estrogen availability for reabsorption by GI
Vitamins and Minerals and cancer
- Folate - decreased risk for pancreatic; increased risk for other cancers with high intake
- Ca - decreased risk for colorectal; higher risk for aggressive prostate (?)
- Vit D - evidence inconclusive, human trials needed - possible reduced risk in colorectal, breast, prostate, and pancreatic cancer
Phytochemicals and cancer
- naturally occurring bio active non-nutritive compounds found in fruits, veg, beans, whole grains - appear to have the ability to stop conversion of healthy cell to cancerous
- coffee (polyphenols), and green tea (catechins) may reduce risk
- have antioxidant activity
- isoflavones (found in soy) may help prevent prostate and breast cancer
- women with BC - limit soy
MNT recommendation - cancer patient with nausea
- small frequent meals
- bland foods - avoid spicy, fried or greasy foods
- crackers by bedside
- make the most of the days you feel well
- anticipatory - behavioral intervention
- medication
MNT recommendations - cancer patient with vomiting
- tiny amounts of clear liquids until under control
- bland diet
- potassium and magnesium rich foods when feeling better
MNT recommendations - cancer patient with constipation
- lots of liquids
- move/exercise
- prunes/prune juice
- high fiber foods
- reduce caffeine
- hot beverages
MNT recommendations - cancer patient with dry mouth (xerostomia)
- artificial saliva, saliva stimulants (lemon), rinses, moist foods, juices, popsicles, broth
- avoid thick nectars, cream soup, thick hot cereal, breads, dry food
MNT recommendations - cancer patients with sore mouth
- cool, smooth, bland foods
- soft or pureed foods
- avoid spicy, salty, acidic foods
MNT recommendations - taste alterations
- offer cold foods, milk products, fruit-flavored supplements
- avoid red meat, chocolate, coffee or tea
- if hypoguesia (mouth blindness) offer strongly flavored food
MNT recommendations - sensitivity to smell
- have someone else cook
- cook outside
MNT recommendations - decreased oral intake
- small frequent meals
- eat in morning
- Megace
MNT recommendations - loss of appetite
- eat by clock rather than by hunger
- eat nutritionally dense foods
- snacks between meals
- plan meals, get help preparing
