A study reported online on June 15, 2011 in the journal Neurology® reveals an association between olive oil consumption and a lower risk of stroke. Olive oil is a common feature of diets consumed in the countries surrounding the Mediterranean, and has been suggested as an important factor in the diet's disease-protective benefit.
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, an ongoing prospective cohort study of vascular risk factors for dementia that includes men and women residing in Bordeaux, Dijon and Montpellier, France. Olive oil consumption frequency was ascertained 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 in dressings 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 unveiled a 41 percent lower risk of stroke among intensive olive oil users compared to those who reported no use. The protective association was significant 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 provided by olive oil consumption) 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." However, he added that "Whether the putative health benefits of a Mediterranean-type diet are due to olive oil itself remains a matter of debate."
"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."