C

cancer prevention CANCER claims more than
500,000 lives each year in the United States, and
nearly nine million Americans are cancer sur-
vivors. Yet all cancers related to TOBACCOuse and
excessive ALCOHOLconsumption are preventable,
and cancer experts believe lifestyle changes could
prevent a third or more of most other cancers.
The first correlation between a controllable
external factor and the development of cancer
occurred more than a century ago with the obser-
vance that cigarette smokers died younger than
nonsmokers. Researchers have since linked ciga-
rette smoking to nearly a dozen types of cancer,
notably lung, laryngeal, esophageal, STOMACH, pan-
creatic, colorectal, prostate, and BREASTcancers as
well as myeloid LEUKEMIA. Over the past 40 years
scientists have established numerous connections
between other external factors and different types
of cancer. Many cancer prevention efforts today
target those connections, most of which are
lifestyle factors. Lifestyle factors associated with an
increased risk for many types of cancer include

• tobacco use (particularly cigarette smoking)


• no regular physical exercise


• EATING HABITSthat favor high-fat, low-fiber, and
  low fruit and vegetable consumption


• OBESITY


• excessive alcohol consumption

Though the links between cancer and some
lifestyle factors are less than finite, health experts
believe lifestyle modifications to minimize the
roles of these factors may play in causing cancer
could reduce the development of new cancers by
about a third and are beneficial for health overall.
Some cancers occur as a consequence of chronic

INFECTION, such as LIVER CANCERthat results from

chronic HEPATITIS. Avoiding hepatitis through vacci-

nation and appropriate preventive practices elimi-

nates the cancers it might otherwise cause.

Other cancer prevention efforts target early

detection of precancerous and cancerous condi-

tions through screening methods. Early detection

allows the highest success for treatment. Nearly all

CERVICAL CANCERresults from infection with HUMAN

PAPILLOMAVIRUS(HPV), which is transmitted sexu-

ally, and nearly all COLORECTAL CANCERarises from

intestinal polyps. Screenings that detect precan-

cerous conditions, such as intestinal polyps

(COLONOSCOPY) and cervical DYSPLASIA (PAP TEST),

permit doctors to intervene before the circum-

stance evolves into one of cancer.

Some health experts advocate taking supple-

ments of antioxidants (such as vitamin C and vita-

min E), and in particular COENZYME Q 10 , to boost the

body’s ability to resist cancerous growth. Clinical

research studies of coenzyme Q10 suggest various

health benefits for this potent antioxidant, though to

date those investigating the cancer-fighting capabili-

ties of other antioxidants have failed to demonstrate

such effect. Consuming substances that decrease

inflammatory markers, such as fish oils and aged

garlic, may also have preventive benefit.

See also CANCER RISK FACTORS; CERVICAL INTRAEPI-

THELIAL NEOPLASIA(CIN); LIFESTYLE AND HEALTH; SCREEN-

ING FOR CANCER.

cardiovascular disease prevention CARDIOVASCU-

LAR DISEASE(CVD) is the leading cause of death and

disability among Americans. It accounts for nearly

a million deaths each year and disables as many as

20 million people, limiting their capabilities for

work and recreational activities. More than 60

million Americans live with some form of CVD.

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