Can Cancer be Prevented?
by Cynthia Stein, M.D., M.P.H.
Special to Education Update
Can cancer be prevented?
Yes. In fact, at the Harvard Center
for Cancer Prevention, we estimate that more than half of
all cancers in the US could be prevented. Each year over
1 million people in this country are diagnosed with some
form of cancer, but this number could be significantly reduced
by basic lifestyle changes. There are some things, like age
and family history, that we can’t
control. However, there are steps that everyone can take to
lower their risk of getting cancer:
Don’t smoke, and avoid second-hand
smoke.
Smoking is the most preventable
cause of death in the US. It causes about 30% of all the
cancer in this country, including cancers of the lung, mouth,
larynx, esophagus, pancreas, cervix, kidney, and bladder.
Smoking also leads to many other health problems, including
heart disease, stroke, lung infections, and pregnancy complications.
Even the smoke from other people’s
tobacco use (second-hand smoke) is harmful, increasing the
risk of lung cancer and heart disease in nonsmokers. Children
exposed to second-hand smoke are at higher risk of sudden infant
death syndrome, asthma, lung infections, and ear infections.
The good news is that as soon as people quit smoking, their
health starts to improve. Quitting smoking is the single best
thing that smokers can do to improve their health.
Maintain a healthy weight.
Excess weight has been linked to a variety of cancers, including
colon, breast, and uterine cancer, and many other chronic diseases,
like diabetes and heart disease. Almost 65% of adults are overweight,
and over 30% are considered obese. For reduction of cancer
risk and other health benefits, we should balance the amount
of calories consumed with regular physical activity.
Be physically active.
Physical activity not only helps
achieve a healthy weight, it also lowers the risk of breast
and colon cancer, osteoporosis, heart disease, and diabetes.
It enhances mood, improves sleep, and helps people reduce
stress. Activity doesn’t need
to be strenuous to be beneficial. Moderate exercise, like brisk
walking, offers health benefits. Physical activity is important
for children since healthy patterns of behavior can be established
at a young age, and exercise in childhood may affect disease
risk later in life. Get at least 30 minutes of physical activity
every day.
Eat a healthy diet.
What we eat can have a significant impact on cancer risk.
Eeating a diet rich in fruits, vegetables, and whole grains
has been linked to a lower risk of multiple cancers and heart
disease. Eating less red meat helps limit the amount of unhealthy
saturated fat in the diet and decreases the risk of cardiovascular
disease, colon cancer, and prostate cancer. While eating a
variety of healthy foods provides most of the vitamins our
bodies need, taking a multivitamin with folate every day can
offer extra protection against colon cancer, heart disease,
and certain birth defects. Important in any healthy diet is
total calories because excess calories from any source can
lead to weight gain.
Limit alcohol.
Alcohol has different effects on different diseases. While
it may help reduce the risk of heart disease, it also increases
the risk of several cancers, including breast, colon, esophageal,
and oral cancer. Alcohol use comes with risk of increasing
blood pressure, weight, heart failure, addiction, suicide and
accidents; therefore nondrinkers should not start drinking.
Drinkers should limit alcohol intake to a moderate amount (1
drink/day for women, 2 drinks/day for men).
Protect your skin from the sun.
Sun exposure causes the majority of skin cancer. Some forms
of skin cancer, like melanoma, can be fatal, and others, such
as basal cell and squamous cell cancer, can be highly disfiguring.
Since about 80% of lifetime sun exposure occurs before the
age of 18, sun protection is critical for children. Adults
need to avoid excess sun to prevent additional skin damage
and to provide good examples for their children. It is best
to avoid extended periods in the sun between 10 am and 4 pm,
use sunscreen with SPF 15 or higher, and wear protective hats
and sunglasses.
Get regular screening tests.
While we don’t have screening
tests for most cancers, we do have tests for colon, breast,
prostate, and cervical cancer. Screening tests can work either
detecting changes before they become cancer or finding cancer
at an earlier and more treatable stage. Screening saves lives,
but only if people get tested. Talk to your doctor about
what tests are right for you.
Make healthy choices.
Of course, each individual is unique,
and it is impossible to predict who will or won’t develop
cancer. However, many healthy life choices offer multiple
benefits, reducing the risk of a variety of cancers and other
chronic diseases. For more information on strategies to prevent
disease, visit www.yourcancerrisk.harvard.edu. Even small
behavior changes can bring significant health benefits and
improve the chances of living a long and healthy life.#
Dr. Cynthia Stein is Instructor in Medicine, Harvard Medical
School and the Harvard Center for Cancer Prevention.
