If people avoided major risk factors for cancer, more
than a third of the 7 million annual deaths from the disease
could be prevented, scientists said.
In a report in The Lancet medical journal, the researchers
estimated how many deaths from 12 types of cancer were
caused by exposure to nine risk factors.
They calculated that smoking, alcohol, obesity, poor
diet, unsafe sex, lack of exercise and other factors contributed
to 2.43 million cancer deaths worldwide in 2001.
"A third of cancer deaths could have been avoided had
those risks been reduced," said Dr Majid Ezzati of the
Harvard School of Public Health in the United States.
"Prevention is probably still our best bet for reducing
cancer deaths. It is by far larger than what we may be
able to achieve using medical technology."
Smoking, which is linked to lung, mouth, stomach, pancreatic
and bladder cancers, is the biggest avoidable risk factor,
followed by alcohol and not eating enough fruits and vegetables.
"Of the 2.43 million deaths, 37 percent of them are from
lung cancer," said Ezzati. "The total lung cancer deaths
in the world are 1.23 million and of those 900,000 of
them are caused by these risk factors."
Smoking has increased in developing countries in the
past few decades so the number of avoidable deaths could
grow, he added.
Obesity also plays a role in colorectal and breast cancer
in high income countries, according to the research.
Infection with the human papillomavirus (HPV) through
unsafe sex is a contributing cause of cervical cancer
in women in sub-Saharan Africa and parts of Asia, mainly
because of a lack of screening and clinical services.
Urban air pollution is a risk factor for cancer in eastern
and southern Asia, while indoor smoke from burning coal
is a particular problem in China.
Ezzati said hepatitis infection, which is linked to liver
cancer, is sometimes spread by the use of contaminated
syringes in health centers in poor countries.
More than 100 scientists around the world contributed
data for the study and reviewed medical evidence.
- Calculate
Your Disease Risk
- More articles
on Preventing Cancer
Reference
Source 89
November
18, 2005