Diet, Alcohol Linked to
Nearly 1/3 of Cancer Cases
Diet is second only to tobacco as a
leading cause of cancer and, along with alcohol, is responsible
for nearly a third of cases of the disease in developed countries,
a leading researcher said.
Dr Tim Key, of the University of
Oxford, told a cancer conference that scientists are still discovering
how certain foods contribute to cancer but they know that diet,
alcohol and obesity play a major role.
"Five percent of cancers could
be avoided if nobody was obese," he said.
While tobacco is linked to about
30 percent of cancer cases, diet is involved in an estimated 25
percent and alcohol in about six percent.
"We know that obesity and alcohol
are important," said Key.
Obesity raises the risk of breast,
womb, bowel and kidney cancer while alcohol is known to cause
cancers of the mouth, throat and liver. Its dangerous impact is
increased when combined with smoking.
Both alcohol consumption and obesity
rates are rising in many countries.
Key told the meeting of the charity
Cancer Research UK that other elements of diet linked to cancer
are still unknown but scientists are hoping that the EPIC study,
which is comparing the diets of 500,000 people in 10 countries
and their risk of cancer, will provide some answers.
Early results of the study have
revealed that Norway, Sweden and Denmark have the lowest consumption
of fruit and vegetables among European countries while Italy and
Spain have the highest. Eating at least five portions of fruit
and vegetables a day is recommended to reduce the risk of cancer.
Key, principal scientist on the
EPIC study, said it is looking at dietary links to some of the
most common cancers including colorectal, breast and prostate.
So far it has shown that obesity
is linked to an increased risk of colorectal cancer, while processed
and red meat also probably raise the chances of developing the
disease and eating lots of fruit and vegetables decrease the odds.
"Hormones are the key factor in
breast cancer. There is currently about a five-fold variation
in breast cancer rates around the world. Much of that variation
is due to parity, the number of children (a woman has) and breast
feeding," Key said.
But he added that obesity and alcohol
can also raise the risk of the disease. Scientists working on
the study have not positively identified any dietary factors associated
with prostate cancer.
Reference Source 89