A Spanish-led team ran a large randomized trial testing whether a traditional Mediterranean diet, enriched with either extra-virgin olive oil or mixed nuts, could prevent heart attacks and strokes better than standard low-fat advice.
Across 7,447 people at high cardiovascular risk followed for nearly five years, major cardiovascular events occurred in 3.8 percent of the olive oil group and 3.4 percent of the nuts group, compared with 4.4 percent on the control diet, a relative reduction of about 30 percent in both diet arms.
The original 2013 paper was retracted and republished in 2018 after irregularities were found in how about 1,600 of the 7,447 participants were assigned, though the corrected analysis reached the same conclusion. It remains one of the largest randomized tests of a whole dietary pattern, rather than a single nutrient, against cardiovascular disease.
Read the original study
A whole diet, tested like a drug.
Source
- Estruch, R., Ros, E., Salas-Salvadó, J., Covas, M.-I., Corella, D., Arós, F., Gómez-Gracia, E., Ruiz-Gutiérrez, V., Fiol, M., Lapetra, J., Lamuela-Raventos, R. M., Serra-Majem, L., Pintó, X., Basora, J., Muñoz, M. A., Sorlí, J. V., Martínez, J. A., Fitó, M., Gea, A., . . . PREDIMED Study Investigators (2018). Primary Prevention of Cardiovascular Disease with a Mediterranean Diet Supplemented with Extra-Virgin Olive Oil or Nuts. New England Journal of Medicine, 378(25), e34. https://doi.org/10.1056/NEJMoa1800389