Virgin olive oil may boost cognition by diversifying gut bacteria, study finds
Key takeaways
- New research has found that virgin olive oil boosts memory and problem-solving skills, while refined olive oil reduces gut bacteria diversity that may mitigate cognitive health.
- Virgin olive oil consumption was linked to a specific beneficial gut bacteria genus, which was responsible for nearly half of participants’ total cognitive improvement.
- Through industrial processing, olive oils lose essential antioxidants and polyphenols necessary for brain protection.
New research suggests that virgin olive oil holds protective cognitive health benefits that stem from its influence on the gut microbiome. A recent study indicates that consuming this form over refined olive oil may improve cognition and diversify gut bacteria, which the authors say are indications of good intestinal and metabolic health.
Conversely, participants in the observational study who consumed refined olive oil exhibited less diverse microbiota over time.
Researchers also pinpointed a genus of gut bacteria, known as Adlercreutzia, which likely plays a major role in virgin olive oil’s brain health benefits.
“This is the first prospective study in humans to specifically analyze the role of olive oil in the interaction between gut microbiota and cognitive function,” says study first author Jiaqi Ni, researcher at the Universitat Rovira i Virgili’s Department of Biochemistry and Biotechnology in Spain.
Two-year cognitive and microbiome screening
Widely recognized as a fundamental component in the Mediterranean diet, olive oil is known for its cardiovascular and metabolic health benefits when compared to animal fats. However, the researchers note that its direct influence on the human brain through the digestive system had not been explored in depth until now.
Their study in Microbiome involved data from 656 overweight or obese people aged between 55 and 75 with metabolic syndrome. This set of risk factors is known to increase the likelihood of developing cardiovascular disease.
Researchers analyzed data on participants’ consumption of different types of olive oil, virgin and refined, and the composition of their gut microbiota through stool samples. At baseline and during a two-year follow-up, participants also completed mental tests, including memory, language, and problem-solving tasks, to assess changes in their cognitive abilities.
Participants consuming virgin olive oil had higher levels of a beneficial gut bacteria associated with a cognitive boost.Participants consuming virgin olive oil were associated with a significantly increased abundance of Adlercreutzia, which was responsible for about half of the boost in their memory and thinking tests.
In contrast, participants who consumed refined common olive oil showed a negative association with cognitive health and a decrease in overall gut microbial diversity.
“This research reinforces the idea that the quality of the fat we consume is as important as the quantity; extra virgin olive oil not only protects the heart, but can also help preserve the brain during aging,” notes Jordi Salas-Salvadó, principal investigator of the study.
The professor from Universitat Rovira, Spain, adds that the research paves the way for new nutrition-based strategies that prevent cognitive decline.
Difference lies in production
The researchers highlight that refined olive oil is obtained exclusively through mechanical procedures, whereas refined olive oil undergoes industrial treatments to remove impurities. This is where the two varieties diverge in terms of health benefits.
Refined oil’s processing tends to degrade the oil’s natural antioxidants, polyphenols, vitamins, and other bioactive compounds that are beneficial to health, note the study authors.
Ni warns that “not all olive oils have benefits for cognitive function” and urges people to consume extra virgin olive oils rather than refined ones.
At the same time, study co-directors Nancy Babio and Stephanie Nishi, underscore the relevance of the results in the current context of healthy aging.
“At a time when cases of cognitive decline and dementia are on the rise, our findings drive home the importance of improving diet quality and, in particular, prioritizing extra virgin olive oil over other refined versions as an effective, simple, and accessible strategy for protecting brain health.”
Earlier this year, the founder of Canaan Palestine shared additional insights with Nutrition Insight about health benefits of extra virgin olive oil, including how it benefits satiety and blood sugar control by triggering the release of GLP-1 hormones. His research is exploring how to extract oleocanthal from olive oil, which could offer anti-inflammatory benefits.
