Chapter 2: Nutrition and Cancer Prevention Flashcards
A cancer survivor is someone who:
Has ever been diagnosed with cancer. At the time of diagnosis, they are considered a survivor. They don’t have have to wait until after they are “recovered”
T of F: Body fatness probably protects against premenopausal breast CA but increases the risk of postmenopausal breast CA
True
What are the AICR/WCRF Recommendations?
- Be as lean as possible within normal range of body weight
- Be physically active as part of everyday life
- Limit consumption of energy-dense foods; avoid sugary drinks
- Eat mostly foods of plant origin
- Limit intake of red meat and avoid processed meats
- Limit alcoholic drinks
- Limit consumption of salt; avoid moldy cereals or pulses
- Aim to meet nutritional needs through diet alone
- Mothers to breastfeed; children to be breastfed
- Survivors follow the same recommendations above
The AICR/WCRF recommendations were developed by an expert panel that reviewed and synthesized the large body of relevant peer-reviewed literature on ______, _______, and ________, aimed at the prevention of cancer as a whole.
Diet, physical activity and cancer
What is a protective hormone that decreases insulin resistance and inflammation and promotes apoptosis?
Adiponectin
AICR/WCRF recommend that those who consume red meat limit intake to what amount per week?
less than 500 g (18 oz) per week
How is breastfeeding beneficial in regards to cancer?
Mother’s risk for both pre and post-menopausal breast CA is reduced
Babies are less likely to become overweight/obese, reducing their risk of cancers that are associated with lifestyle/obesity
AICR/WCRF recommendations regarding alcohol consumption include:
Alcohol works synergistically with tobacco, multiplying the risk of mouth and throat CAs.
A modest increase in breast CA risk occurs even at intake of the recommended max daily intakes (max amounts are one/day for women, two/day for men)
True or False: High dose of Vitamin E has been shown to reduce the risk of colon cancer
False
What are two supplements/nutrients that may promote the risk of prostate cancer?
Vitamin E and Calcium - both shown to increase risk
A plant-based diet helps reduce the risk of cancer by what mechanisms?
Epigenetic effect (changes in gene expression)
Reducing levels of circulating hormones that promote cell proliferation
Provide fermentable fiber to the intestional microbiota, promoting normal colon cell development and possible reducing inflammation
True or False: Beta-carotene and Vitamin E are two examples of high-dose supplements that increase the risk of cancer
True
Body Fatness is related to influencing cancer risk by:
Decreased levels of adipose hormone adiponectin, which decreases insulin resistance and inflammation
What two nutrients may be beneficial as a supplement if blood levels are low, but aren’t beneficial once levels are optimal?
Vitamin D and Selenium
Both the AICR/WCRF and the ACS recommend exercise to prevent cancer. What are their recommendations?
AICR/WCRF:
30 minutes every day and as fitness improves, aim for 60 minutes of moderate or 30 minutes of more vigorous activity daily
Also limit sedentary habits such as watching TV
ACS:
adults get 150 minutes of moderate activity of 75 minutes of vigorous activity each week
children/adolescents be physically active for a min of 60 minutes every day, including at least 3 days/week of vigorous activity
Foods containing selenium and foods containing lycopene have been shown to protect against what type of cancer?
Prostate
The risk of colorectal cancer increases by an estimated ____ percent for every ____ grams of processed meat consumed daily.
18%
50 grams
T or F: Soy foods have been proven to increase cancer risk in both animals and humans
False - only in rat models, not in humans
What is the American Cancer Society’s recommendation on sodium intake and cancer prevention?
There is no recommendation from ACS
T or F: Increased years of amenorrhea can reduce Breast CA risk
True
Adipose tissue is the primary site of what hormone in post-menopausal women?
Estrogen
The AICR recommends a waist circumference of ___ in men and ___ in women?
Men - 37”
Women - 31.5”
Body fatness has been linked to several types of cancer. What are these cancers and what percentage of these cases can be attributed to overweight/obesity?
esophageal, pancreatic, colorectal and endometrial, kidney, and breast. (possibly gallbladder)
20%
A predominantly plant based diet is associated with decreased cancer risk. List categories of animal foods and comment on their relationship to cancer risk.
red meat (beef, lamb, pork):
- increases colorectal cancer risk
- limit consumption to >18 ounces per week
processed meat (meats preserved by smoking, curing, salting, or by the addition of chemical preservatives, i.e. ham, bacon, hot dogs, salami, etc):
- increased colorectal cancer risk
- limit consumption to very little, if any
There is a lack of evidence associated with increase or decrease in cancer risk with regards to consumption of poultry, fish, and eggs. The research with dairy is conflicted.
List mechanisms through which physical activity can influence cancer risk.
reduced weight gain and easier maintenance of a healthy level of body fat
improved insulin sensitivity and reduced insulin levels
decreased levels of bioavailable sex steroid hormones
more rapid gut transit time reducing exposure of colon cells to carcinogens
improved immune function
Dietary Supplement information - Calcium
Probably protect against colorectal CA, but above 1,500 mg daily increases prostate CA risk
Dietary Supplement information - Beta-carotene
Initially showed to lower risk of lung CA, but now shows that in smokers that took high-dose supplements developed cancer at higher rates than the placebo
Dietary Supplement information - Vitamin E
High dose vitamin E supplements may promote modest increase in the risk of prostate CA
Dietary Supplement information - Selenium
Food/supplements may reduce prostate CA growth in its aggressive form, but not overall risk. Suggested may be beneficial to supplement in people how already have low selenium levels due to dietary intake, but to not supplement those with adequate serum levels already
Dietary Supplement information - Vitamin D
May reduce cancer risk throughout the cancer process, but still being studied. Current study results are inconsistent when trying to target a specific level
Emerging Topic - Omega-3 Fatty Acids
May protect against cancer by decreasing inflammation, cell proliferation, and angiogenesis while increasing apoptosis. However, exact amounts of EPA, DHA, ALA and such is difficult in studies
Emerging Topic - Soy Foods
Isoflavones in soy are studied as possible cancer risk due to initial research in rats that showed increased growth in ER+ breast CA. However, we now know that human metabolize them differently than rats.
Studies that show moderate soy consumption (1-2 standard servings) saw no increased Breast CA risk, possible decreased risk.
Emerging Topic - Flaxseed
Highly studied in Breast CA. Primarily focused on its conversion to plant lignans and ALA, it may reduce risk of breast and other CAs. Too limited for a recommendation at this time.
Emerging Topic - Green Tea
Primarily studied for epigallocatenchin gallate (EGCG). Results are limited, but may help with antioxidant capacity.
