Use the outline below to guide your study of the material in this
lesson. The outline indicates those topics the instructor feels
are most important for you to learn in the course. You should read
all the pages assigned, open and study the links, and read the terms
in the glossary.
Malignancy depends on frequency of smoking, tar content, duration of habit
Passive inhalation of second-hand smoke causes as many deaths as air pollution
Diet: ~ 20-30% of fatal cancers
Animal (saturated fat) in general and red meat in particular: colon and rectum; implicated
in prostate cancer
Salt: high intake may lead to stomach cancer; in very young children in Southeast Asia leads to
cancer of the nasopharynx
Hot drinks increase risk of esophageal cancer
Eating too few vegetables and fruits is associated with higher cancer rates, perhaps by the absence of
antioxidants to neutralize free radicals
Some natural chemicals may block cell proliferating signals from steroids, e.g. estrogens
Overeating is linked to certain cancers: breast and prostate
Obesity is a cause of cancer of the endometrium and contributes to postmenopausal breast cancer;
increases risk for cancers of the colon, kidney, and gallbladder
Alcohol in large quantity, especially with smoking, increases risk of cancer of upper respiratory
and digestive tracts
Radiation: ~ 2% of fatal cancers
High frequency UV-B rays damage DNA; cause 90% of skin cancers
Radon - radioactive gas is emitted from the earth in some locations
Low frequency electric and magnetic fields: perhaps a small risk for childhood leukemia
Radio-frequencies - no empirical evidence for increased risk
Nuclear radiation - a potential risk for those few exposed
Work, medications, microbes: ~ 5% of fatal cancers from occupational exposure