Extra virgin olive oil has long been praised as a key part of the Mediterranean diet, known for supporting heart health and reducing the risk of chronic disease.
Now, new research suggests it may also help protect the brain — and it does so by influencing the bacteria living in our gut.
Scientists from the Universitat Rovira i Virgili in Spain and collaborating research centers studied how olive oil consumption affects cognitive function through the gut microbiome, the community of microorganisms that live in the digestive system.
Their findings, published in the journal Microbiome, show that extra virgin olive oil may play an important role in maintaining memory and thinking skills as people age.
The study followed 656 adults aged 55 to 75 who were overweight or obese and had metabolic syndrome, a condition that increases the risk of heart disease and diabetes.
Over two years, researchers tracked participants’ diets, focusing on the type of olive oil they consumed — extra virgin or refined — along with changes in their gut bacteria and cognitive performance.
Participants who regularly consumed extra virgin olive oil showed improvements in cognitive function compared with those who mainly used refined olive oil.
They also had greater diversity in their gut microbiota, which is considered a sign of better digestive and metabolic health. In contrast, people who consumed refined olive oil tended to show less microbial diversity over time.
Researchers identified a particular group of gut bacteria called Adlercreutzia that appeared to be linked to the beneficial effects of extra virgin olive oil on brain health.
This suggests that some of the oil’s protective effects may come from how it shapes the balance of bacteria in the gut, which in turn can influence the brain through the so-called gut-brain connection.
The key difference between extra virgin and refined olive oil lies in how they are produced. Extra virgin olive oil is made through mechanical processes without chemical treatment, preserving natural antioxidants, polyphenols, vitamins, and other beneficial compounds. Refined olive oil, on the other hand, undergoes industrial processing that removes impurities but also strips away many of these health-promoting substances.
Researchers emphasize that not all olive oils offer the same benefits. Choosing high-quality extra virgin olive oil appears to be important for supporting both heart and brain health. The findings also highlight that the quality of dietary fats matters just as much as the amount consumed.
As populations age and concerns about dementia and cognitive decline grow, simple dietary changes could play a meaningful role in prevention. Scientists say prioritizing extra virgin olive oil over refined oils may be an accessible way to support long-term brain health.
While more research is needed, the study strengthens the idea that what we eat affects not only our physical health but also our mental well-being. By nurturing beneficial gut bacteria, extra virgin olive oil may help protect the brain and preserve cognitive function later in life, offering yet another reason to include this traditional ingredient in a healthy diet.
Source: KSR.
