Researchers found that older people who used olive oil intensively — meaning they regularly cooked with it and used it in salad dressing — were 41 percent less likely to have a stroke than those who rarely consumed it.
The lead author of the six-year study, Cecilia Samieri of the University of Bordeaux in France, said why olive oil might help reduce the risk of strokes was unclear. But it might result from people replacing less healthful saturated fats with mono-unsaturated olive oil, she added.
“We can’t infer from our study which aspects of olive oil prevent stroke,” Samieri said. But “it may be a substitution effect.” Thus, eating fewer saturated fats improves the health of olive oil users. Prior research had documented olive oil’s anti-inflammatory benefit, she added.
Properties of the oil itself, including oleic acid or polyphenols, could also hold the secret to the oil’s protective effect, said Samieri, a post-doctoral faculty member in the university’s department of nutritional epidemiology. Polyphenols are antioxidant nutrients that reduce inflammation in the vascular system, according to the study. Oleic acid, a fatty acid, makes up 80 percent of olive oil.The study is published in the June 15 online edition of Neurology.