World of Chem: Food March 6 Diet and Cancer
Diet and Cancer
Stems from cancer the crab zodiac (their legs stem out just like cancer in your body)
Treatments: surgery, chemotherapy, radiation
o Save lives and extend lives
o Slash, poison and burn nicknames respectively
o Radiation is often the last resort because the salivary glands are damaged (if radiation
near neck or mouth) and individuals do not have many taste opportunities left. Salivary
glands also dry up.
Five year survival rates have risen from 50% to 66%
Several vaccine strategies are now being researched:
o Peptide based
o Cell based
o The FDA has approved a vaccine called Provenge for prostate cancer and it has
lengthened life by several months. It stimulates the immune system.
Diet and Cancer: projected numbers for 2012 deaths.
o Most common cancers:
Lung 160,340 combined.
Colon, rectum 51,690 combined (decreased).
Breast 39,510 combined.
Prostate 28,170 combined. (decreased)
o In 2006, cancer deaths in the U.S. fall for the first time in 70 years. Death rate falling but
population keeps rising.
Explanation: smoking on decline; cancer spotted earlier and treated better.
Cases and deaths of cancer in USA, India and Japan are very different. Thus food intake is very
o Prostate: 1043 cases; 179 deaths in USA and much less in India.
Increase in lung cancer particularly for women was so high from 1950-1980 that it made the
total cancer deaths increase.
o Women smoking a lot starting 1960. When they got older, lung cancer incidents
1985 Men stopped smoking so lung cancer rates decreasing.
Cancer rates are decreasing but very slowly
o 1-2% per year reduction on colorectal cancer
o Divide 70 by the % change to get an idea of the halving or doubling of the process
o 70 years for the rate to divide by half if only 1% per year reduction!
Cancer rates under age 65:
o Lung cancer (for females) increasing 70%; all cancers decreasing 10%. Melanomas
increasing 10% - Australia especially!
Cancer rates over age 65:
o 250% increase for females in lung cancer
o Melanomas increase 77%
o All cancers increase 17%
122: oldest woman ever. World of Chem: Food March 6 Diet and Cancer
In the U.S. >500,000 persons will die of cancer this year.
o About 1,500 per day
o One per minute
o 1 per 10 minutes for Canada
Prominent cancer deaths in North America:
o Infections, sexual behaviour, occupational top two: unbalanced diet, followed by
Risk factor prevalence in U.S.: hypertension, high serum cholesterol, cigarette smoking all going
down. But obesity increasing!
News from the Womens Health Initiative: Reducing Total Fat Intake May Have Small Effect on
Risk of Breast Cancer, No Effect on Risk of Colorectal Cancer, Heart Disease, or Stroke.
o The results from the largest ever clinical trial of low-fat diet are reported in three paper in
the February 8, 2006 edition of the Journal of the American Medical Association (JAMA)
o Fat didnt make much difference
o 50,000 post-menopausal women aged 50-80 followed for 8 years
o Cost $400 million dollars!
Mutagenic: an agent or substance (including a virus or ionizing radiation) that can bring about a
permanent alteration to the DNA of a gene.
o We consume them on a regular basis
Teratogenic: an agent or substance (including a virus or ionizing radiation) that can cause
malformation of an embryo or fetus.
o Thalidomide the most famous. Good for leprosy (Hansens disease), originally for
morning sickness in the first trimester. 10,000 victims alive today.
Carcinogenic: an agent or substance (including a virus or ionizing radiation) that can cause
The altered gene often can be repaired. Eventually, errors will occur. Cell division stays on, and
tumours may result (cell growth that hasnt been shut down). Tumours may interfere with regular
body functions. Tumour cells invade other cells.
o Angiogenesis: malignant cells secrete chemicals promoting new blood vessels and the
o Want to tackle angiogenesis in treatment.
o Metastasis (pieces break off) occurs and the tumour spreads.
o Tumour fighting can take place at many places to inhibit some of these steps.
Of the 330 million people in North America, 10 million are living with cancer.
What about the press and the food connection?
o The press: yes/no/yes/no back and forth between whether something is a cancer causing
agent. E.g. coffee.
o A cup of coffee contains about 10 mg of known carcinogens. (acrylamide, caffeic acid,
benzene, styrene, formaldehyde, furfural) in animal studies.World of Chem: Food March 6 Diet and Cancer
o There are more natural rodent carcinogens by weight in an average cup of coffee than
there are potentially carcinogenic synthetic pesticide residues in the average North
American diet for a year.
o Insecticidal agents in vegetables to get rid of their own pests, not to affect humans.
Treatment of cancer going to take at least 10-15 years.
Human Equivalent Rat Potency (HERP) index by Bruce Ames shows what will kill a rat and
what concentration of it will kill a human.
o The smaller the index, the less impact it has.
o Clofibrate: cholesterol lowering drug. Highest HERP index.
o PCBs and tap water very low HERP index.
The difficulty with studies:
o Variations in studies
Nature of carcinogen
Even the wood chips in the rat cages should be constant.