It’s tough to navigate all of the health claims of various food products out there. Many claims are unsubstantiated, and those that have evidence behind them are often not derived from high quality data. In that context, I was impressed to see a recent randomized controlled clinical trial, suggesting that a Mediterranean diet supplemented with extra virgin olive oil reduces the risk of breast cancer in postmenopausal women.
The PREDIMED trial randomized 4,282 women to receive either a Mediterranean diet supplemented with extra virgin olive oil; a Mediterranean diet supplemented with nuts; or a control diet with advice to reduce dietary fat.
After 4.8 years, they found that the olive oil supplemented diet reduced the risk of breast cancer by 62%, and the nut supplemented diet reduced the risk by 41%, compared to the control diet.
While these numbers look super impressive, the absolute numbers are actually fairly small: rates of breast cancer per 1000 person years were:
- 1.1 for the extra virgin olive oil group
- 1.8 for the nuts group
- 2.9 for the control group
A word of caution: One must also be careful not to eat too many calories in oil or nuts – these are highly calorie dense foods which can quickly add up and contribute to weight struggles if eaten to excess, and obesity is a known risk factor for breast cancer.