Women who
participated in the study who added extra-virgin olive oil to their diet had a
62 percent lower risk of breast cancer over the next five years or so,
according to researchers at the University of Navarra in Pamplona.
The study was
done in Spain, where people presumably eat the Mediterranean diet. The diet is
characterized by lots of salad, fruit, vegetables, nuts, a little fish, a
little lean meat, a small amount of cheese — and olive oil, of course. Wine is
also served at meals.
The volunteers in
the trial, however, were given extra counseling, and a weekly supply of either
extra-virgin olive oil or mixed nuts.
The 4,282 women
in the trial were, on average, about 68 and obese, with an average body massindex of 30.4 — just over the line for clinical obesity.
“After a median
follow-up of 4.8 years, we identified 35 confirmed incident cases of breast
cancer," Miguel Martínez-González and colleagues wrote in the Journal of
the American Medical Association's JAMA
Internal Medicine.
The study is
considered unusually strong because people are randomly assigned to different
diets. It accounts for the possibility that people who choose to follow a
certain healthy diet pattern may do other things differently, too.
The study's
already shown some startling effects — the healthful diet with extra nuts and
olive oil has been shown to help people live longer and avoid heart disease
cutting the risk of heart attacks and strokes by 30 percent, and it may also
help preserve their brains.
Now breast cancer
is added to the list - but only among those who got the extra olive oil. The
women who got the nut mixture also had a slightly lower risk of breast cancer,
but the results were not strong enough to be considered significant.
"TheMediterranean dietary pattern has attracted considerable attention because,
historically, breast cancer rates have been lower in Mediterranean countries
than in Northern or Central European countries or the United States," the
researchers wrote.
It took a lot of
olive oil to get the protection - it had to make up 15 percent or more of
calories.
What's in
extra-virgin olive oil that's so special? Extra-virgin means the olive oil is
squeezed mechanically, without the use of heat or chemicals that can alter its
chemical properties. It usually has a stronger flavor than processed olive oil.
"Several
biological mechanisms could explain the putative anticarcinogenic properties of
extra virgin olive oil," the researchers wrote.
"All types
of olive oil provide a high supply of monounsaturated fatty acids, mainly oleic
acid, as well as squalene, whereas extra virgin olive oil also contains various
biologically active compounds, such as the polyphenols oleocanthal, oleuropein,
hydroxytyrosol, and lignans," they added.
Oleic acid may
act directly on cancer-causing genetic mutations, studies have shown. Squalene
may help reverse damage caused by oxidation, which is a damaging chemical
reaction linked to both cancer and heart disease.
original content can be found at: http://www.nbcnews.com/health/cancer/olive-oil-may-help-prevent-breast-cancer-too-n426991