Risk of Colon Cancer Increases with Age but Can Be
Significantly Reduced by Exercise
Fourth most common cancer in men and women; more
common in people over 50
Feb. 12, 2009 - An ambitious new study has added
considerable weight to the claim that exercise can lower the risk for
colon cancer, one of those cancers that targets older people.
Researchers found that people who exercised the most were 24 percent
less likely to develop the disease than those who exercised the least.
Researchers at Washington University School of
Medicine in St. Louis and Harvard University combined and analyzed
several decades worth of data from past studies on how exercise affects
colon cancer risk.
Research
demonstrates even moderate physical activity is a significant factor in
diminishing the risk or increasing the likelihood of survival for certain
cancers in women
"What's really compelling is that we see the
association between exercise and lower colon cancer risk regardless of
how physical activity was measured in the studies," says lead study
author Kathleen Y. Wolin, Sc.D., a cancer prevention and control expert
with the Siteman Cancer Center at Barnes-Jewish Hospital and Washington
University.
"That indicates that this is a robust association
and gives all the more evidence that physical activity is truly
protective against colon cancer."
Colorectal cancer is the third most common type of
cancer. Each year more than 100,000 people in the United States are
diagnosed with colon cancer and about 40,000 are diagnosed with rectal
cancer. The study suggests that if the American population became
significantly more physically active, up to 24 percent, or more than
24,000, fewer cases of colon cancer would occur each year.
Wolin's report was published Feb. 10, 2009 through
advance online publication in the British Journal of Cancer. In the
study, she and her colleagues gathered the results from all relevant
studies published in English on the effect of physical activity on colon
cancer risk.
They eliminated from consideration any studies that
combined both colon and rectal cancer because exercise has not been
shown to affect rectal cancer risk including such studies would have
led to an underestimation of the effect of exercise on colon cancer
risk. In all, they analyzed 52 studies going back as far as 1984, making
their analysis the most comprehensive to date.
They found that the protective effect of exercise
held for all types of physical activity, whether that activity was
recreational, such as jogging, biking or swimming, or job related, such
as walking, lifting or digging.
"The beneficial effect of exercise holds across all
sorts of activities," says Wolin, also assistant professor of surgery.
"And it holds for both men and women. There is an ever-growing body of
evidence that the behavior choices we make affect our cancer risk.
Physical activity is at the top of the list of ways that you can reduce
your risk of colon cancer."
The difference between people who were the most
physically active and those who were the least varied from study to
study in Wolin's analysis. As an example, in a 2007 study by Wolin and
colleagues, women who walked the most realized a 23 percent reduction in
their risk of colon cancer. Those highly active women walked briskly for
five to six hours each week. By comparison, the women in that study who
walked the least walked only a half hour each week.
Background Information
Source: Wolin KY, Yan Y, Colditz GA, Lee I-M.
Physical activity and colon cancer prevention: a meta-analysis. British
Journal of Cancer. Feb. 10, 2009 (advance online publication).
Washington University School of Medicine's 2,100
employed and volunteer faculty physicians also are the medical staff of
Barnes-Jewish and St. Louis Children's hospitals. The School of Medicine
is one of the leading medical research, teaching and patient care
institutions in the nation, currently ranked third in the nation by U.S.
News & World Report. Through its affiliations with Barnes-Jewish and St.
Louis Children's hospitals, the School of Medicine is linked to BJC
HealthCare.
Siteman Cancer Center is the only federally
designated Comprehensive Cancer Center within a 240-mile radius of St.
Louis. Siteman Cancer Center is composed of the combined cancer research
and treatment programs of Barnes-Jewish Hospital and Washington
University School of Medicine. Siteman has satellite locations in West
County and St. Peters, in addition to its full-service facility at
Washington University Medical Center on South Kingshighway.
Information on Colorectal Cancer
(Colon Cancer, Rectal Cancer)
By National Cancer Institute
Cancer of the colon or rectum is also called
colorectal cancer. In the United States, it is the fourth most common
cancer in men and women. Caught early, it is often curable.
It is more common in people over 50, and the risk
increases with age. You are also more likely to get it if you have
● Polyps - growths inside the colon and rectum that may become
cancerous
● A diet that is high in fat
● A family history or personal history of colorectal cancer
●
Ulcerative colitis or
Crohn's disease
Symptoms can include blood in the stool, narrower
stools, a change in bowel habits and general stomach discomfort.
However, you may not have symptoms at first, so screening is important.
Everyone who is 50 or older should be screened for colorectal cancer.
Colonoscopy is one method that your doctor can use to screen for
colorectal cancer. Treatments for colorectal cancer include surgery,
chemotherapy, radiation or a combination.
What Are the Key Statistics for
Colorectal Cancer?
By American Cancer Society
Excluding
skin cancers, colorectal cancer is the third most common cancer
diagnosed in both men and women in the United States. The American
Cancer Society estimates that about 108,070 new cases of colon cancer
(53,760 in men and 54,310 in women) and 40,740 new cases of rectal
cancer (23,490 in men and 17,250 in women) will be diagnosed in 2008.
Overall, the lifetime risk for developing
colorectal cancer is about 1 in 19 (5.4%). This risk is slightly higher
in men than in women. A number of other factors (described in
"What are the risk factors for colorectal cancer?") may also affect
a person's risk.
Colorectal cancer is the third leading cause of
cancer-related deaths in the United States when men and women are
considered separately, and the second leading cause when both sexes are
combined. It is expected to cause about 49,960 deaths (24,260 men and
25,700 women) during 2008.
Feb. 12, 2009 - An ambitious new study has added
considerable weight to the claim that exercise can lower the risk for
colon cancer, one of those cancers that targets older people.
Researchers found that people who exercised the most were 24 percent
less likely to develop the disease than those who exercised the least.
Excluding
skin cancers, colorectal cancer is the third most common cancer
diagnosed in both men and women in the United States. The American
Cancer Society estimates that about 108,070 new cases of colon cancer
(53,760 in men and 54,310 in women) and 40,740 new cases of rectal
cancer (23,490 in men and 17,250 in women) will be diagnosed in 2008.
(Patient Education Institute) Also available
in
(National
Cancer Institute)