A study in the journal Neurology found an association between olive oil consumption and a lower risk of stroke. This was a French study involving 7,625 participants.

Cécilia Samieri, PhD, of the University of Bordeaux and her associates analyzed data from 7,625 participants aged 65 and older in the Three-City Study involving Bordeaux, Dijon and Montpellier, France. Olive oil consumption frequency was determined from dietary intake documented upon enrollment between 1999 and 2000, and was categorized as no use, moderate use, or intensive use (characterized by the use of olive oil multiple times daily, both as a dressing and in cooking).

During a median follow-up period of 5.25 years, 148 strokes occurred in the study population. Adjusted analysis of the data revealed a 41 percent lower risk of stroke among intensive olive oil users compared to those who reported no use. The protective association was found for ischemic stroke, but not hemorrhagic stroke.

In a secondary study of 1,245 subjects for whom plasma fatty acid measurements were available, those with the highest levels of plasma oleic acid (a biological marker of oleic acid intake from olive oil) had a 73 percent reduction in stroke risk compared to those whose levels were lowest.

American Academy of Neurology member Nikolaos Scarmeas, MD of Columbia University remarked in an accompanying editorial that "Although the Mediterranean-type diet shares many features with many other healthy dietary patterns, it is distinct in its high fat content, mainly from olive oil."

"Our research suggests that a new set of dietary recommendations should be issued to prevent stroke in people 65 and older," commented Dr Samieri, who is affiliated with the National Institute of Health and Medical Research (INSERM) in Bordeaux. "Stroke is so common in older people and olive oil would be an inexpensive and easy way to help prevent it."

It’s noteworthy to me that this protective effect from olive oil was observed without any kind of dietary restrictions. This is France we’re talking about,  and French cooking.  Besides using olive oil, they also use vast amounts of butter, meat, and other foods that are suspected of being atherogenic. Yet, without limiting anything else, the inclusion of olive oil made a startling difference in stroke risk.

However, I believe it makes a big difference whether you use olive oil as a dressing on a big green salad or if you fry lamb chops in it. Imagine if, in addition to using a high quality extra-virgin olive oil, you largely steer your daily diet towards unrefined plant foods, including many fruits and vegetables, plus leafy greens (both raw and cooked) and legumes, whole grains, etc. I dare say that you are going to do fabulously well.

I use extra-virgin olive oil every day, and it is the only oil I use.