Fatty Foods 'boost cancer risk'
Eating large amounts of
saturated fat or red meat may increase the risk of breast cancer, a study suggests.
Previous studies have also indicated a link. However,
scientists have been unsure as to whether other factors, such as being obese,
play a role.
This latest study, published in the British Journal of Cancer,
suggests eating large amounts of these foods can by themselves increase the
risk.
Experts said the findings highlighted the importance of
healthy eating.
Dr Norman Boyd and colleagues at the Ontario Cancer
Institute in
The looked at 45 separate studies, involving 580,000
healthy women and 25,000 breast cancer patients.
They analyzed the data from these studies, taking into
account other known and suspected risk factors for breast cancer.
Eating fats
They then compared women with the highest and lowest fat
intake, in order to assess whether or not dietary fat was contributing to the
disease.
There are two types of fats - saturated and unsaturated
fats. Saturated fats are sometimes referred to as "bad" fats. They
are found in animal products such as butter, cheese, whole milk, ice cream,
cream, and fatty meats
There are two types of unsaturated fats - monounsaturated
and polyunsaturated. These are sometimes referred to as "good" fats.
They are found in olive oil and nuts.
The researchers found that women who ate high amounts of
saturated fat were on average around 20% more likely to develop breast cancer
than women who ate low amounts.
By comparison, women who ate large amounts of
monounsaturated fats were around 10% more likely to develop the disease. This
figure is not deemed significant in scientific terms.
Overall, women who ate large amounts of fats were 13% more
likely to develop breast cancer, a small but significant figure.
The study also found that women
who at large amounts of meat were 17% more likely to develop breast cancer than
those who ate little or none.
The researchers said their figures may actually
underestimate the true risk.
"We already know that being obese can increase the
risk of a range of cancers, but evidence is building that eating large amounts
of fat, particularly the saturated kind, can independently increase risk,"
said Dr Boyd.
"Our analysis of all the available research suggests
there is indeed an association with saturated fat and breast cancer.
"The increase in risk seems fairly modest, even among
very high consumers of fat, although the difficulties in measuring dietary
intake mean we could be under-estimating the true scale of the effect.
"In any case, the effect seems to be over and above
the increase in risk from obesity and underlines the message that high
consumption of fat is bad for your health."
Healthy eating
Dr Lesley Walker, director of cancer information at Cancer
Research
"It's been very difficult to separate out the effects
of dietary fat and obesity and previous studies have been inconclusive.
"But by combining data from a wide range of studies
using different methods and including a very large number of people, this
research provides the strongest indication yet that dietary fat has an
independent effect on the risk of breast cancer.
"Tying down the various dietary contributors to cancer
is important, as it will allow us to give the best possible advice about how to
avoid cancer.
The effect of dietary fat looks quite small, but the results add weight to the importance of a healthy, balanced diet, low in saturated fat and containing plenty of fruit and vegetables.