"Primary Prevention of Cardiovascular Disease with a Mediterranean Diet" NEJM, February 25, 2013
A total of 7447 persons were enrolled in this Spanish study (age range, 55 to 80 years). Three groups: (1) control diet, (2) Meditteranean Diet with Nuts, and (3) Meditteranean Diet with Extra Virgin Olive Oil.
Significantly less cardiovascular events and death in group (2) and (3) (P=0.009 and 0.02) but only group (3) showed a noticeable (P=0.11) reduction of death from all causes.
|Fig.1 from the Spanish study.|
Please notice no reduction of death from all causes in the nuts group!
To me this study is a clear endorsement of the type of fatty acids characteristic of olives, as being unequivocally healthy, while nuts may lower one risk while increase some other.
Why were nuts as good as extra virgin olive oil (EVOO) for cardio but not as good in terms of total death? Was there some other cause of death that was positively correlated with nuts (but not with EVOO), which neutralized the benefit of eating nuts for cardio-vascular health? I am guessing here but it is quite possible that polyunsaturated fat from nuts may have contributed to cancer risk whereas the mono-unsaturated and saturated fats from the olive oil did not!
See also NYT article.