01
What the evidence says
The Spanish multicenter trial enrolled 7,447 adults at high cardiovascular risk and compared a Mediterranean diet supplemented with extra-virgin olive oil, one supplemented with nuts, and control advice to reduce fat. In the revised report, major cardiovascular events occurred in 3.8%, 3.4%, and 4.4% respectively over a median 4.8 years, with adjusted analyses favoring both Mediterranean programs.
Sources for this section: [1]
02
How to use the finding
The intervention was a supported dietary pattern with education and supplied foods, not proof that adding olive oil or nuts to any existing diet produces the same result. Event differences were driven importantly by stroke, and participants were older Spanish adults at high risk. Use the study as one component of dietary guidance together with broader trial and observational evidence, feasibility, allergies, energy needs, and preference.
Sources for this section: [1]
03
Limits and open questions
Investigators found household members and some sites had not followed individual randomization as intended. The original paper was withdrawn and revised analyses attempted to account for deviations. That response improves transparency but does not recreate perfect randomization. Readers should preserve both the favorable result and the reduced certainty when explaining the study.
Sources for this section: [1]
Sources
- Primary Prevention of Cardiovascular Disease with a Mediterranean Diet Supplemented with Extra-Virgin Olive Oil or NutsNew England Journal of Medicine · 2018DOI 10.1056/NEJMoa1800389