Recent research reveals a critical difference in how various olive oils impact cognitive health as we age. While olive oil is widely considered healthy, a study published in the journal Microbiome suggests that the type of olive oil matters significantly. Specifically, virgin olive oil may protect against cognitive decline, while refined olive oil could accelerate it. This isn’t merely about fats; it’s about how these oils interact with your gut microbiome, which directly affects brain function.
The Study Findings: A Clear Divide
Researchers followed 656 participants aged 55 to 75 with pre-existing metabolic risks (a group already prone to cognitive decline). Over two years, they tracked olive oil consumption and measured cognitive performance. The results were striking:
- Virgin olive oil (VOO) consumption correlated with improved cognitive function.
- Common (refined) olive oil (COO) consumption linked to lower gut microbiota diversity and faster cognitive decline.
The study points to a key mediator: the gut bacterium Adlercreutzia. Virgin olive oil appears to promote its growth, leading to positive changes in brain health.
Why Virgin Olive Oil Works Differently
The critical factor is polyphenols. Virgin olive oil retains these potent antioxidants and anti-inflammatory compounds (like hydroxytyrosol and oleuropein), which are largely stripped away during refining. Refined olive oil still contains the healthy fats, but lacks the compounds that feed beneficial gut bacteria.
This connects to the gut-brain axis : a direct communication pathway between your gut microbiome and your central nervous system. What you feed your gut influences signals sent to your brain through immune, neural, and metabolic pathways. Virgin olive oil provides “premium fuel” for gut bacteria, while refined oil offers little nutritional value to the microbiome.
How to Choose the Right Oil: A Practical Guide
To maximize brain health benefits, follow these guidelines:
- Read the label carefully : Look for “extra virgin” or “virgin” olive oil. Avoid labels that say “pure,” “light,” or simply “olive oil” – these are refined.
- Check the harvest date : Olive oil degrades over time. Use within 12-18 months of harvesting.
- Proper storage is key : Store in a dark, cool place to protect polyphenols.
- Certifications matter : Look for seals like the California Olive Oil Council or PDO (Protected Designation of Origin) from Europe.
- Use generously : Integrate virgin olive oil as a primary fat source in your diet.
The Bottom Line
This study demonstrates that not all olive oils are created equal. Choosing virgin olive oil over refined options is a simple yet powerful step toward protecting cognitive function. By supporting a healthy gut microbiome, you’re directly influencing brain health, making this one of the most impactful dietary upgrades you can make.
