According to a report by Anne-Julie Tessier, RD, PhD, a postdoctoral fellow at the Harvard T.H. Chan School of Public Health, published by the American Society for Nutrition, consumption of olive oil may reduce the risk of fatal dementia by 28% compared to using such products as margarine, butter, or mayonaise. Here is a link to the article:
https://www.eurekalert.org/news-releases/995547

According to this report, “The study is the first to investigate the relationship between diet and dementia-related death. Scientists analyzed dietary questionnaires and death records collected from more than 90,000 Americans over three decades, during which 4,749 study participants died from dementia.”

“The results indicated that people who consumed more than half a tablespoon of olive oil per day had a 28% lower risk of dying from dementia compared with those who never or rarely consumed olive oil. In addition, replacing just one teaspoon of margarine and mayonnaise with the equivalent amount of olive oil per day was associated with an 8-14% lower risk of dying from dementia.”

While those who use olive oil on a regular basis may have healthier diets, Tessier found that the “relationship between olive oil and dementia mortality risk in this study was independent of overall diet quality.”

Moveover, Tessier said that “Some antioxidant compounds in olive oil can cross the blood-brain barrier, potentially having a direct effect on the brain” and “It is also possible that olive oil has an indirect effect on brain health by benefiting cardiovascular health.”