Mediterranean Diet and Invasive Breast Cancer Risk Among Women at High Cardiovascular Risk in the PREDIMED Trial: A Randomized Clinical Trial

This Spanish study of 4,282 women (60-80 years) at high cardiovascular disease risk found that those assigned to a Mediterranean diet supplemented with extra-virgin olive oil had a reduced risk of breast cancer (rate of 1.1 per 1000 person-years vs 2.9 for control diet).

This research was carried out as part of the PREDIMED study, which was designed to test the effects of a Mediterranean diet, one based on plant foods, fish, and extra virgin olive oil, on the primary prevention of cardiovascular disease. Breast cancer incidence was a prespecified secondary outcome of the trial for women without a prior history of breast cancer (n = 4152).

 

The authors acknowledge that their findings need to be confirmed in longer-term and larger studies, as they come from a secondary analysis of a previous trial and are based on few incident cases (only 35 confirmed new cases of breast cancer during the median follow-up period of five years).