Olive-Oil Lovers at Lower Risk of Strokes
Akey component of the so-called Mediterranean diet, olive oil may help protect against strokes caused by blocked arteries. French researchers report that people who used the most olive oil for cooking and salad dressings were 41% less likely to suffer an ischemic stroke. The results, the scientists concluded, suggest olive oil may be a major protective component of the Mediterranean diet.
Ccilia Samieri, PhD, of Universit Bordeaux, and colleagues followed 7,625 people age 65 and older without a prior stroke in the French cities of Bordeaux, Dijon and Montpelier. At the studys start, 22.8% reported not using olive oil at all, 40% used it moderately for cooking and in dressings, and 37.2% were classified as intensive olive oil consumers. Those users consumed olive oil always or most often for cooking and in dressings. Samieri notes, In this large sample of older subjects, we could not assess the actual quantities of olive oil consumed.
A second study group of 1,245 people were tested for blood levels of oleic acid, an indirect marker for olive-oil consumption, and then also followed for incidence of strokes. Those with the highest blood levels of oleic acid were 73% less likely to suffer a stroke than those with the lowest levels.
During an average 5.25 years of followup, those in the primary group suffered 148 ischemic strokes, while the secondary group saw 27 total strokes. Only the most intensive olive oil consumers in the primary group saw a statistically significant association with reduced stroke risk. Moderate intake was associated with a 20% lower stroke incidence, but this wasnt significant. The study didnt distinguish between types of olive oil, but almost all the olive oil consumed in France is extra-virgin.
Before you dash to the grocery store, however, Alice H. Lichtenstein, DSc, director of Tufts HNRCA Cardiovascular Nutrition Laboratory, cautions, There are other factors associated with people who use olive oil that may have accounted for the outcome. Were high olive oil users wealthier? Were they more likely to drink wine?
The researchers controlled for known stroke risks as well as fish, meat, cereal and fruit and vegetable consumption, other types of added fats, physical activity levels and body mass index (BMI). In an accompanying editorial in Neurology, however, Nikolaos Scarmeas, MD, and Luc Dauchet, MD, PhD, cautioned that its impossible to entirely separate olive oil consumption from the foods with which its used: Olive oil is usually added to other foods (i.e., fruits and vegetables, legumes, cereals and fish) and may contribute indirect benefits by increasing the palatability and consumption of foods that may have health-promoting potential.
The editorial warned that the apparent protective benefits of olive oil against stroke can be claimed with confidence only if the observations… withstand the trial of randomized interventions.
TO LEARN MORE: Neurology, online before print; abstract at dx.doi.org/10.1212/WNL.0b013e318220abeb.