Eat Well, Get
Smoking -- Prevent Cancer
If you wanted to start today to reduce your chances
of getting cancer, what would you have to do? Lose excess weight,
get more exercise, eat a healthy diet and quit smoking.
Those basic behavior changes would have a tremendous impact on
the incidence of the most prevalent types of cancer — lung,
breast, prostate and colon cancer — says Graham Colditz,
M.D., Dr.P.H., associate director of Prevention and Control at
the Siteman Cancer Center at Washington University School of Medicine
in St. Louis and Barnes-Jewish Hospital. "We estimate that
more than 50 percent of cancer incidence could be prevented if
we act today on what we already know," Colditz says.
Every year, more than 500,000 Americans die from cancer. The
National Cancer Institute estimates that on average each person
who dies from cancer loses 15 years of life, and altogether cancer
deaths were responsible for nearly 8.7 million person-years of
life lost in 2003, the most recent year for which the data were
"The loss of life and earning potential and the social impact
of cancer are enormous," Colditz says. "Reducing risk
by adopting lifestyle changes like quitting smoking and losing
weight isn't always easy, but it may help to remember that these
behavior changes can also reduce your risk of heart disease, diabetes,
stroke and osteoporosis."
Colditz's recommendations for preventing cancer also include
avoiding excess alcohol consumption, taking a multivitamin with
folate and protecting yourself from too much sun and from sexually
Colditz recently became leader of the Siteman Center's cancer
prevention program having previously headed the Harvard Center
for Cancer Prevention.
Estimates hold that 20 to 30 percent of the most common cancers
in the United States stem from being overweight or physically
inactive. Research has linked weight gain to common cancers such
as breast and colon cancer, as well as uterine, esophageal and
renal cancers. "Women who lose weight in their adult years
reduce their risk of breast cancer significantly," Colditz
Furthermore, he asserts that a clear connection exists between
higher levels of physical activity and lower incidence of cancer.
"For example, even after diagnosis of breast cancer, physical
activity has an impact on recurrence and survival," he says.
What people breathe in, drink or eat can influence whether they
get cancer. It's well known that smoking is associated with lung
cancer, but less commonly understood is that smokers also are
more likely to get colorectal cancer as well as kidney, pancreatic,
cervical and stomach cancers.
"The rate at which risk drops after stopping smoking varies
for different cancer sites," Colditz says. "But it's
very clear that within five to 10 years there will be a 50 percent
reduction in cancer risk compared to people who keep smoking."
Although some recent evidence has suggested that wine and other
alcoholic beverages may contain beneficial components, other data
show that overconsumption of alcohol increases the possibility
of getting oral, esophageal, breast and other cancers.
Eating a plant-based diet can help protect against cancer. People
who eat diets rich in fruits and vegetables have a lower danger
of cancers of the colon, mouth, pharynx, esophagus, stomach and
lung. Diets high in red meat and animal fat increase the probability
of certain cancers. "There's a strong, consistent relation
between higher intake of red meat and higher risk of colon cancer,"
High intake of folate, a B vitamin, may protect a person from
cancer, and epidemiological studies suggest that low folate status
may play an important role early in cancer development. Colditz
says experts recommend taking a multivitamin that contains folate
Reducing long-term exposure to the sun and to artificial light
from tanning beds, booths and sun lamps can lower the danger of
getting non-melanoma skin cancer. Avoiding burns and other damage
from these sources — especially in children and teens —
can reduce the chances of getting melanoma skin cancer.
Certain viral infections have also been strongly linked to cancer
development. Some of the most important of these are human papillomavirus
(HPV), a cause of cervical cancer, hepatitis B and C viruses,
major causes of liver cancer, and Helicobacter pylori, which accounts
for the majority of cases of stomach cancer. HPV can be spread
by sexual contact, and vaccine-conferred immunity results in a
marked decrease in precancerous lesions.
As with the new cervical cancer vaccine, advances in chemoprevention
will likely add to the prevention potential that comes from healthy
lifestyle choices. "In the future we'll be seeing a range
of new preventative strategies," Colditz indicates. "For
example, the National Cancer Institute has a trial looking at
selenium as a supplement to prevent cancer. And research shows
that antiestrogens may reduce the risk of breast cancer by 60
to 80 percent in women after menopause."