Obesity and cancer
Obesity is a risk factor for many forms of cancer.
Overall between 30% and 40% of all cases of cancer - three to four
million cases worldwide every year - could be prevented by better
diets, more physical activity and maintenance of appropriate body
weight. Experts agree that avoiding becoming overweight, avoiding
fatty foods, eating more fruit and vegetables and staying active
contributes to preventing cancer.
The 660-page World Cancer Research Fund report - Food, Nutrition
and the Prevention of Cancer: a global perspective - reviewed 4,500
studies to examine the links between dietary factors and 18 specific
cancers.
A panel of 15 experts suggested that recommended diets, together
with maintenance of physical activity and appropriate body mass,
can in time reduce cancer incidence by 30 - 40%. At current rates,
on a global basis, this represents 3 - 4 million cases of cancer
per year that could be prevented by dietary and associated means.
Action to prevent cancer is, therefore, rational, timely and important,
and should be a major priority and responsibility for international
agencies, governments, industry, non-governmental organisations,
medical and health authorities, and for all working in the public
interest at international, national and community level.
International Agency for Research into Cancer
The International
Agency for Research into Cancer - part of the World Health Organization
- convened a conference of experts to consider overweight and cancer
in February 2001. They found that obesity and lack of exercise contribute
to up to a third of cancers of the colon, breast, kidney, and digestive
tract. The expert group said that although there was no direct evidence,
hormonal changes produced by weight loss may help reduce risks of
some cancers, especially breast and uterine cancer. They said governments,
the food industry, international agencies, the media, communities,
and individuals all need to work together to modify the environment
so that it is less conducive to weight gain.
Estimates of the percentage of weight-related cancer across the
European Union show that in the worst example, nearly half the cases
of endometrial cancer could be prevented by avoiding with overweight
and obesity. Click
here for tables showing the proportion of cancer and actual weight-related
cases in the EU.
Links
UICC
WORLD CANCER CAMPAIGN
International
Agency for Research into Cancer Lyon, France
WORLD
CANCER RESEARCH FUND: Food, nutrition and the prevention of cancer:
a global perspective.
Washington,
DC, American Institute for Cancer Research, 1997
Link
to World Cancer Research Fund UK
European
Code Against Cancer - Point 4: "Avoid becoming overweight,
increase physical activity and limit intake of fatty foods"
Nature
- Cancer Epidemiology in the last century and the next decade -
Prof Julian Peto
Obesity
and Cancer
Obesity and cancer research
Researchers at the famous Karolinska Institute in Sweden looked
at more than 28,000 hospital patients treated during 1965-1993.
Within their study, they found overall a 33% excess incidence of
cancer in obese persons - 25% in men and 37% in women.
They found risks were higher for cancers of the small intestine,
colon , gallbladder, pancreas, larynx , renal parenchyma, bladder,
cervix uteri, endometrium, ovary, brain and connective tissue and
for lymphomas.
They also noted a higher risk for Hodgkin's disease in men and
for non-Hodgkin's lymphoma in women, but found the association of
obesity with risk of breast, prostate and pancreas cancers was modified
by age. Their conclusion: obesity is associated with more forms
of cancer than previously reported.
(Cancer Causes Control 2001 Jan;12(1):13-21)
Wolk A, Gridley G, Svensson M, Nyren O, McLaughlin JK, Fraumeni
JF, Adam HO
|
