Similarly, early laboratory tests and population studies clearly
showed that high-fat diets increased colon cancer. Yet studies comparing
individuals with high or low fat intake have not always supported
a link with colon cancer.
Now a report in Carcinogenesis suggests that fats differ
in their effects. Research shows that the composition of the body's
cells actually changes with changes in dietary fat. Polyunsaturated
oils create unstable cells that are more vulnerable to the kind
of damage that can begin the cancer process. Omega-3 fatty acids
(found in fatty fish) and monounsaturated fats (like olive and canola
oils) don't seem to promote damage.
Risk may be more than a question of fat and fiber. Several studies
have found substantial increases in risk related to frequency of
eating red meat, but this is not supported consistently. Other studies
suggest that it may not be a matter of red meat versus white, but
of how it is cooked. When meat, fish or poultry is cooked at high
temperatures (grilling, broiling, frying) substances form that can
damage our genes in a way that allows cancer to begin developing.
Cooking at lower temperatures, marinating or cooking food partially
in a microwave before grilling or broiling helps reduce formation
of these substances.
A major report on diet and cancer risk from the American Institute
for Cancer Research (AICR) found convincing evidence that eating
an abundance of vegetables and fruits offers protection against
colon cancer. While researchers puzzle over which vitamins, phytochemicals
and fiber types might be most helpful, the bottom line is that boosting
our intake to at least five servings of a variety of fruits and
vegetables daily could probably lower colon cancer risk by 30 to
According to AICR, regular exercise is another strongly supported
route to lower risk. Maintaining a healthy weight has also shown
some relationship to lower colon cancer risk. It is unclear, however,
whether this is due to actual effects of body fat or to differences
in exercise or eating habits.
Despite recent confusing reports, colon cancer remains one of
our most preventable cancers. Although fat and fiber consumption
continue to get most of the limelight, the most effective plan to
lower your cancer risk also involves plenty of fruits and vegetables
and a healthy amount of exercise.
# # #
AICR offers the AICR Nutrition Hotline (1-800-843-8114).
Open 9 a.m. to 5 p.m. EST, Monday-Friday, this free service allows
you to ask a registered dietitian your questions regarding diet,
nutrition and cancer. AICR's Internet Web address is www.aicr.org.
The American Institute for Cancer Research is the only major cancer
charity focusing exclusively on the link between diet, nutrition
and cancer. The Institute provides a wide range of consumer education
programs that have helped millions of Americans learn to make changes
for lower cancer risk. AICR also supports innovative research in
cancer prevention and treatment at universities, hospitals and research
centers across the U.S. The Institute has provided more than $50
million in funding for research in diet, nutrition and cancer.