Extra virgin olive oil is known for supporting heart and metabolic health and has long been a cornerstone of the Mediterranean diet. Now, new research suggests it may also help protect the brain. Scientists have discovered that its benefits extend beyond the body to the mind, potentially supporting cognitive function through the gut microbiome.
A study led by researchers from the Human Nutrition Unit of the University of Rovira i Virgili (URV), the Pere Virgili Health Institute (IISPV), and CIBERobn points to a meaningful link between extra virgin olive oil, gut bacteria, and brain health.
Study investigating olive oil, gut microbiome, and brain health
“This is the first prospective study in humans to specifically analyze the role of olive oil in the interaction between the gut microbiome and cognitive function,” explains Jiaqi Ni, first author of the paper and a research fellow in the URV Department of Biochemistry and Biotechnology.
The study followed 656 adults between the ages of 55 and 75 who were overweight or obese and had metabolic syndrome, a set of risk factors that increase the likelihood of developing cardiovascular disease. As part of the PREDIMED-Plus project, scientists tracked the participants’ diets over two years, including their intake of virgin and refined olive oil, and conducted detailed analyzes of their gut microbiota. They also monitored changes in cognitive performance over time.
Virgin olive oil linked to improved cognition and gut diversity
The results showed clear differences depending on the type of olive oil consumed. Participants who regularly used virgin olive oil experienced improved cognitive function and a more diverse gut microbiome, which is widely thought to be a sign of good intestinal and metabolic health. In contrast, people who consumed refined olive oil tended to have lower microbiome diversity over time.
Researchers also identified a specific group of gut bacteria known as Adler’s kreuzia that may be involved in these benefits. Its presence may serve as an indicator of a positive relationship between virgin olive oil intake and maintenance of cognitive function. These results suggest that part of the oil’s brain-supporting effects may come from how it reshapes the gut microbiome.
Why extra virgin olive oil is better
The difference between extra virgin olive oil and refined olive oil lies primarily in the method of production. Extra virgin olive oil is obtained using mechanical methods that help preserve natural compounds. Refined olive oil, on the other hand, undergoes industrial processing to remove impurities.
This purification process improves shelf life and taste consistency, but also reduces beneficial components such as antioxidants, polyphenols, vitamins, and other bioactive substances. Jiaqi Ni says, “Not all olive oils are effective for cognitive function,” stressing the importance of choosing extra virgin varieties.
The quality of dietary fat is important for brain health
These findings further strengthen the evidence that diet plays an important role in both cardiovascular and cognitive health through its influence on the gut microbiome. The study’s lead researcher, Jordi Salas Salvado, emphasized the importance of choosing high-quality fats, saying, “This study supports the idea that the quality of the fats we consume is as important as the quantity. Extra virgin olive oil not only protects the heart, but also helps protect the brain as we age.”
He also said that identifying the specific microbial profiles associated with these benefits “paves the way to new nutrition-based prevention strategies to preserve cognitive function.”
Simple dietary changes for an aging society
Co-directors Nancy Babio and Stephanie Nishi highlight the broader implications of the findings as the population ages. “At a time when cognitive decline and cases of dementia are on the rise, our findings drive home the importance of improving diet quality, and especially prioritizing extra virgin olive oil over other refined versions as an effective, simple and accessible strategy to protect brain health.”
The study was led by the Human Nutrition Unit of URV’s Department of Biochemistry and Biotechnology, with contributions from the CIBER Department of the Pere Virgili Health Institute (IISPV-CERCA) and the Carlos III Health Institute’s Physiology of Obesity and Nutrition (CIBEROBN). Researchers from the PREDIMED-Plus consortium also participated, as well as collaborators from international institutions such as Wageningen (Netherlands) and Harvard University (USA).
