The 35 diagnosed cases of breast cancer in 4,282 women is a very low number of cases. This could make the relative reduction in risk seem high. Because the researchers weren’t studying breast cancer, they don’t know how many of the women had regular screening mammograms. It could be that few women following the Mediterranean diet supplemented with olive oil were getting mammograms, so weren’t diagnosed with breast cancer. It also could be that the women in the control group had an overall higher risk of breast cancer than the women in the olive oil group. We just don’t know. It’s not clear if any risk reduction benefits are from the extra virgin olive oil alone or because it was being consumed along with a Mediterranean diet. Whether or not the women followed their prescribed diet was based on their answers to a 14-question food survey that they filled out roughly every 3 months. It’s possible that some or many of the women didn’t clearly remember what they ate for the previous 3 months or didn’t stick to their prescribed diets. The women in the study were all white, Spanish, between 60 and 80 years old, and at high risk of cardiovascular disease. So the results apply only to that group of women -- it’s not good science to apply these findings to all women.