Data from the PREDIMED clinical trial found that women who ate a version of the Mediterranean diet supplemented with extra virgin olive oil were 62% less likely to be diagnosed with breast cancer when compared with women who were asked to simply reduce the overall amount of fat in their diets. The Mediterranean diet consists primarily of fruits, vegetables, whole grains, fish and olive oil.
Other studies have found similar results for Mediterranean-style diets and prostate cancer. The recent study at Harvard University found that men who ate a Western diet high in fat, processed foods and red meat were 2.5 times more likely to die from prostate cancer than men who ate a Mediterranean-style diet rich in vegetables, fruits, whole grains, fish and legumes. See the Summer/Fall 2015 QUEST for more information.
The PREDIMED trial primarily focused on cardiovascular disease and was designed to determine if the Mediterranean diet would affect cardiovascular risk. The results came from a small number of cases of breast cancer found in study participants and thus need to be confirmed in longerterm and larger studies. Of the 4,282 women in the study, only 35 were diagnosed with invasive breast cancer.
The PREDIMED results were published in the journal JAMA Internal Medicine in September.