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The Health Benefits of Olive Oil

Quick Takes

💓 Heart Health Game-Changer: The PREDIMED study was so successful it had to be stopped early for ethical reasons - participants consuming 3 tablespoons of extra virgin olive oil daily saw a 35% reduction in cardiovascular deaths within just 4-5 years.

🧠 Brain Booster: Unlike cardiovascular benefits that plateau around 3 tablespoons daily, cognitive benefits from olive oil don't show an obvious ceiling. Studies using 4.5-6 tablespoons daily report further significant improvements in memory and verbal fluency compared to lower intakes.

☠️ Bone Builder: Women in the PREDIMED trial who consumed extra virgin olive oil had a 50% reduction in osteoporotic fractures - a finding that could revolutionize how we think about bone health in aging.

🔬 Quality Matters: High-phenolic olive oil (with 800-1000+ mg/kg polyphenols) is a better choice for all uses. It outperformed regular EVOO in a 2025 study, improving cholesterol profiles even at lower doses (1 tablespoon vs. 3 tablespoons) when total phenolic content was matched.

👶 Across the Lifespan: Olive oil works hard for humans of all ages, protecting maternal brain health during pregnancy, improving weight gain in preterm infants, and reducing neurodegeneration risk by 29% in adults.

Favorite Finds

You Can Safely Cook With EVOO

Recent and robust research endorsed and summarized by UC Davis confirms that cooking with extra virgin olive oil is safe and doesn’t pose health risks related to oxidation, free radical formation, or toxic byproducts at typical culinary temperatures. The notion that olive oil should only be used cold due to a moderate smoke point is a myth not supported by current evidence. #evooeverywhere

High-Phenolic EVOO Sources

Finding truly high-phenolic extra virgin olive oil can be challenging since most grocery store bottles don't list polyphenol content or harvest dates.

In the San Francisco Bay Area my favorite source is Amphora Nueva.

If you don’t live near an olive oil store, you may consider online sources that list the phenolic content. Anything under 400 is considered low, anything above 800 is high. The benefit of having a local store is tasting the oils. While some oils have a lot of one polyphenol, imparting a certain taste, others have less of that one and more of another.

My discovery writing this newsletter is that I don’t get enough olive oil most days. Thus I decided to start a daily tablespoon of a really high phenolic option, PJ Kabos’s “Phenolic Shot.” I just got my first bottle and was surprised that it is not really that bitter at all (the above is an affiliate link, but honestly, this whole newsletter is a massive conflict of interest as I am of Greek origin in the first place, and my son just started working at an olive oil store!).

Olive Oil Recipes

• A cookbook with traditional recipes from grandmothers in Greece

• A free PDF from the Culinary Institute of America

Learn to make:

• Classic Pesto - Fresh basil, pine nuts, garlic, EVOO, +/- parmesan

• Argentinian Chimichurri - Parsley, oregano, garlic, red wine vinegar, EVOO

• Provençal Tapenade - Olives, capers, anchovies, garlic, lemon, EVOO

• Greek Melitzanosalata (Eggplant Salad) - Roasted eggplant, garlic, lemon or vinegar, herbs, EVOO

• Spanish Romesco - Roasted peppers, almonds, garlic, sherry vinegar, EVOO

• Lebanese Muhammara - Roasted red peppers, walnuts, pomegranate molasses, EVOO

These recipes not only taste incredible but maximize your daily olive oil intake through delicious, traditional preparations that have nourished Mediterranean populations for centuries. You can freeze pesto and chimichurri and defrost as needed throughout the winter. You can improve on not only the cheaper olive oils used in commercial preparations, but also reduce your exposure to the plastic packaging and lids of pesto from stores. You can use many different greens to make pesto.

Deep Dive:

The Science Behind Olive Oil's

Extraordinary Health Benefits

Extra virgin olive oil (EVOO) stands as one of the most scientifically validated functional foods, with mounting evidence supporting its role in preventing chronic disease and promoting longevity. Recent research reveals that EVOO's benefits extend far beyond simple fat replacement, involving complex interactions between bioactive compounds and human (and bacterial) physiology.

Cardiovascular Protection: Beyond the Headlines

The cardiovascular benefits of olive oil consumption are among the most robust findings in nutritional research. Meta-analyses of prospective cohort studies demonstrate a 15-19% reduction in cardiovascular disease events and mortality with higher olive oil intake compared to low-intake groups (Xia et al., 2022). These observational findings are supported by dose-response relationships that appear to plateau around 20g daily in population studies.

The landmark PREDIMED randomized controlled trial provided even more compelling evidence. This study randomized high-cardiovascular-risk participants to receive either a low-fat diet, Mediterranean diet with nuts, or Mediterranean diet with EVOO (Guasch-Ferré et al., 2014). The EVOO group, consuming an average of 3 tablespoons daily, experienced such dramatic benefits - a 35% reduction in cardiovascular deaths - that the study was terminated early for ethical reasons.

The mechanisms underlying these protective effects involve both the monounsaturated fatty acid profile and bioactive polyphenols. Oleic acid, comprising 55-83% of EVOO's fat content, exerts anti-inflammatory effects by inhibiting NF-κB pathways, prevents LDL oxidation, and improves lipid profiles by activating cholesterol transport (Milena & Maurizio, 2025). Simultaneously, polyphenolic compounds like hydroxytyrosol and oleocanthal provide antioxidant protection through ROS scavenging and upregulation of endogenous antioxidant enzymes. The result is healthier, more pliable blood vessels.

Cognitive Benefits: No Ceiling Effect

While cardiovascular benefits may plateau at moderate intakes, cognitive benefits likely continue to accrue at higher levels. While regular EVOO intake improves global cognition, memory, and verbal fluency in older adults (Fazlollahi et al., 2023), studies employing the highest intakes (30-40g daily) demonstrate significant advantages over lower consumption or Mediterranean diet alone.

The MICOIL pilot study provided particularly compelling evidence, demonstrating cognitive improvements in mildly cognitively impaired patients after just 12 months of high-phenolic EVOO supplementation (Tsolaki et al., 2020). Mechanistic studies suggest these benefits result from improved blood-brain barrier function, reduced neuroinflammation, and potential reductions in cerebral amyloid burden (Kaddoumi et al., 2022).

Large-scale observational studies support these experimental findings. In the Nurses' Health Study cohort, participants consuming more than 7g daily of olive oil experienced a 29% decreased risk of neurodegenerative disease mortality, with benefits continuing to increase with higher consumption levels (Guasch-Ferré et al., 2022).

Cancer Prevention: Emerging Evidence

Cancer protection represents another promising area of olive oil research. The PREDIMED trial demonstrated a 17% reduction in cancer mortality among participants consuming EVOO (Guasch-Ferré et al., 2022), while observational studies suggest even more substantial benefits. The Valencia Nutrition Survey, following participants for 18 years, found that consuming ≥2 tablespoons daily (27g) was associated with a 51% lower risk of cancer mortality compared to non-users (Torres-Collado et al., 2022).

Perhaps most remarkably, an Italian cohort study revealed that participants consuming >50g EVOO daily experienced a 60% reduction in gastrointestinal cancer deaths, with the highest consumption quartile continuing to show additional benefit compared to moderate intake levels (30-50g daily) (Bonfiglio et al., 2024). These findings suggest that unlike cardiovascular outcomes, cancer protection may not exhibit a clear plateau effect at higher intakes.

The Polyphenol Advantage

Recent research has shifted focus toward EVOO's polyphenolic compounds, which vary dramatically between products (50-1000 mg/kg) depending on cultivar, processing, and storage conditions.

A 2025 randomized trial comparing high-phenolic EVOO (1021 mg/kg phenols at 8g daily) with moderate-phenolic EVOO (414 mg/kg at 20g daily) - both providing matched total phenolic intake - found superior lipid profile improvements in the high-phenolic group (Kourek et al., 2025). This suggests that phenolic concentration, not just total olive oil volume, may be crucial for optimal health benefits.

NERD CORNER: The key bioactive polyphenols include:

• Secoiridoids: The most abundant class, unique to the Oleaceae family, encompassing oleuropein, ligstroside, and their aglycones like oleacein and oleocanthal (D’Archivio et al., 2022).

• Phenyl-alcohols: Hydroxytyrosol (HT) and tyrosol (Tyr) (D’Archivio et al., 2022).

• Lignans: Pinoresinol and 1-acetoxypinoresinol (D’Archivio et al., 2022).

• Phenolic Acids: Gallic, protocatechuic, caffeic, and coumaric acids (D’Archivio et al., 2022).

• Flavonoids: Luteolin and apigenin, though present at lower concentrations (D’Archivio et al., 2022).

These compounds collectively exert robust antioxidant, anti-inflammatory, vasodilatory, and lipid-modulating effects (Esposito & Mandalà, 2025; D’Archivio et al., 2022).

• Antioxidant Effects: EVOO polyphenols directly scavenge reactive oxygen species (ROS), chelate metals, and upregulate endogenous antioxidant enzymes, thus combating oxidative stress (Esposito & Mandalà, 2025; D’Archivio et al., 2022). Hydroxytyrosol, for instance, is a potent free radical scavenger and stimulates mitochondrial biosynthesis (D’Archivio et al., 2022).

• Anti-inflammatory Effects: Polyphenols inhibit key inflammatory pathways such as NF-kB, and suppress pro-inflammatory cytokines like IL-1, IL-6, and TNF-α, as well as enzymes like COX-1, COX-2, and mPGES-1 (Esposito & Mandalà, 2025; D’Archivio et al., 2022). Oleocanthal, in particular, inhibits cyclooxygenase (COX) 1 and 2 in a dose-dependent manner, mirroring the action of ibuprofen and demonstrating greater potency at equimolar concentrations (D’Archivio et al., 2022). Oleuropein also inhibits proinflammatory cytokine synthesis and lipoxygenase activity (D’Archivio et al., 2022).

• Endothelial Function and Vasodilation: EVOO improves endothelial function by enhancing nitric oxide (NO) bioavailability, promoting vasodilation, and supporting vascular integrity (Esposito & Mandalà, 2025). Polyphenols directly protect blood vessels (Esposito & Mandalà, 2025).

• Lipid Modulation: Oleic acid improves lipid profiles by improving cholesterol transport and preventing LDL oxidation (Esposito & Mandalà, 2025). EVOO enhances HDL function and reduces oxidative stress, while also reducing LDL cholesterol and triglycerides (Esposito & Mandalà, 2025).

Gut Bacteria, AGAIN!

The NU-AGE trial demonstrated that elderly individuals with greater baseline microbiome diversity gained more metabolic and anti-inflammatory improvements from Mediterranean diet interventions (Ghosh et al., 2020), highlighting the importance of the gut-polyphenol interaction in mediating EVOO's health effects.

A crucial and emerging mechanism involves the two-way interaction between EVOO polyphenols and the gut microbiota (GM) (Esposito & Mandalà, 2025; D’Archivio et al., 2022).

• Polyphenols Modify GM: EVOO polyphenols act as prebiotics, stimulating the growth of beneficial bacteria (e.g., Lactobacillus spp., Bifidobacterium spp., Akkermansia spp.) and inhibiting pathogenic species (e.g., Clostridium spp., Helicobacter pylori) (Esposito & Mandalà, 2025; D’Archivio et al., 2022). This can promote a GM anti-inflammatory environment (Rodriguez-Garcia et al., 2020).

• GM Modify Polyphenols: Most complex polyphenols are not absorbed in the small intestine but reach the colon where the GM extensively metabolize them into simpler, more bioactive phenolic acids and metabolites (D’Archivio et al., 2022). These metabolic modifications significantly affect their biological activity and bioavailability (D’Archivio et al., 2022).

• Impact on Metabolites: EVOO inhibits the formation of Trimethylamine N-oxide (TMAO), a gut microbiota-derived metabolite associated with inflammation and atherosclerosis in animal studies (Esposito & Mandalà, 2025). EVOO can also increase levels of adiponectin (Esposito & Mandalà, 2025).

Broader Health Implications

Beyond cardiovascular and cognitive benefits, olive oil consumption has been associated with improvements across multiple health domains. Observational studies report an 18% reduction in respiratory disease mortality (Guasch-Ferré et al., 2022), while experimental evidence suggests benefits for autoimmune conditions including rheumatoid arthritis and multiple sclerosis (Casas et al., 2018).

Bone health represents another emerging area of interest. PREDIMED participants consuming EVOO experienced a 50% reduction in osteoporotic fractures (García-Gavilán et al., 2018), while animal studies demonstrate that olive oil polyphenols prevent bone mineral density loss and improve bone architecture in rodent postmenopausal osteoporosis models (El-Shafaey et al., 2025).

Clinical Translation and Practical Recommendations

The totality of evidence suggests that EVOO consumption, particularly of high-phenolic varieties, provides substantial health benefits across multiple domains. While cardiovascular benefits may plateau around 20-25g daily (approximately 1.5 tablespoons), cognitive and cancer protection benefits appear to continue accruing at higher intakes, potentially up to 50g daily (3.5 tablespoons).

However, quality matters significantly. High-phenolic EVOO demonstrates superior benefits even at lower doses, emphasizing the importance of polyphenolic content over mere volume. Consumers should prioritize products with recent harvest dates (within 6-12 months), high polyphenolic content when available, and proper storage in dark containers to preserve bioactive compounds.

The Mediterranean approach of incorporating EVOO into daily meals through traditional preparations - pestos, tapenades, and vegetable-based dishes - provides both palatability and health optimization, supporting the sustainable adoption of this remarkable functional food.

References

Bonfiglio, C., Reddavide, R., Cisternino, A. M., Campanella, A., Fontana, L., & Giannelli, G. (2024). Protective effect of extra virgin olive oil on cancers, gastrointestinal cancers, and all-cause mortality: A competing risk analysis in a Southern Italian cohort. Cancers, 16(4), 789.

Casas, R., Estruch, R., & Sacanella, E. (2018). The protective effects of extra virgin olive oil on immune-mediated inflammatory responses. Endocrine, Metabolic & Immune Disorders-Drug Targets, 18(1), 23-35.

D'Archivio, M., Santangelo, C., Silenzi, A., Scazzocchio, B., Varì, R., & Masella, R. (2022). Dietary EVOO polyphenols and gut microbiota interaction: Are there any sex/gender influences? Antioxidants, 11(8), 1519.

El-Shafaey, E. S., Ali, E., Elkomy, M., Rizk, M. A., Altuwaijri, S., & Albarrak, S. (2025). Is extra virgin olive oil a promising remedy for reducing the impact of postmenopausal osteoporosis? An experimental study. Frontiers in Veterinary Science, 12, 1347892.

Esposito, M., & Mandalà, M. (2025). Exploring the Cardiovascular Benefits of Extra Virgin Olive Oil: Insights into Mechanisms and Therapeutic Potential. Biomolecules, 15(2), 284.

Fazlollahi, A., Motlagh Asghari, K., Aslan, C., Noori, M., Nejadghaderi, S. A., Araj-Khodaei, M., Sullman, M. J. M., Karamzad, N., Kolahi, A. A., & Safiri, S. (2023). The effects of olive oil consumption on cognitive performance: A systematic review. Frontiers in Nutrition, 10, 1097207.

García-Gavilán, J. F., Bulló, M., Canudas, S., Martínez-González, M. A., Estruch, R., Giardina, S., Fitó, M., Corella, D., Ros, E., & Salas-Salvadó, J. (2018). Extra virgin olive oil consumption reduces the risk of osteoporotic fractures in the PREDIMED trial. Clinical Nutrition, 37(1), 329-335.

Ghosh, T. S., Rampelli, S., Jeffery, I. B., Santoro, A., Neto, M., Capri, M., Giampieri, E., Jennings, A., Candela, M., Turroni, S., Zoetendal, E. G., Hermes, G. D. A., Elodie, C., Meunier, N., Brugere, C. M., Pujos-Guillot, E., Berendsen, A. M., De Groot, L. C. P. G. M., Feskins, E. J. M., ... O'Toole, P. W. (2020). Mediterranean diet intervention alters the gut microbiome in older people reducing frailty and improving health status: The NU-AGE 1-year dietary intervention across five European countries. Gut, 69(7), 1218-1228.

Guasch-Ferré, M., Hu, F. B., Martínez-González, M. A., Fitó, M., Bulló, M., Estruch, R., Ros, E., Corella, D., Recondo, J., Gómez-Gracia, E., Fiol, M., Lapetra, J., Serra-Majem, L., Muñoz, M. A., Pintó, X., Lamuela-Raventós, R. M., Basora, J., Buil-Cosiales, P., Sorlí, J. V., ... Salas-Salvadó, J. (2014). Olive oil intake and risk of cardiovascular disease and mortality in the PREDIMED Study. BMC Medicine, 12, 78.

Guasch-Ferré, M., Li, Y., Willett, W. C., Sun, Q., Sampson, L., Salas-Salvadó, J., Martínez-González, M. A., Stampfer, M. J., & Hu, F. B. (2022). Consumption of olive oil and risk of total and cause-specific mortality among U.S. adults. Journal of the American College of Cardiology, 79(2), 101-112.

Kaddoumi, A., Denney, T. S., Jr., Deshpande, G., Robinson, J. L., Beyers, R. J., Redden, D. T., Praticò, D., Kyriakides, T. C., Lu, B., Kirby, A. N., Beck, D. T., & Merner, N. D. (2022). Extra-virgin olive oil enhances the blood-brain barrier function in mild cognitive impairment: A randomized controlled trial. Nutrients, 14(23), 5102.

Kourek, C., Makaris, E., Magiatis, P., Zouganeli, V., Benetou, V., Briasoulis, A., Xanthopoulos, A., Paraskevaidis, I., Melliou, E., Koudounis, G., & Orfanos, P. (2025). Effects of high-phenolic extra virgin olive oil (EVOO) on the lipid profile of patients with hyperlipidemia: A randomized clinical trial. Nutrients, 17(2), 287.

Milena, E., & Maurizio, M. (2025). Exploring the cardiovascular benefits of extra virgin olive oil: Insights into mechanisms and therapeutic potential. Biomolecules, 15(1), 92.

Rodriguez-Garcia, C., Sanchez-Quesada, C., Algarra, I., & Gaforio, J. J. (2020). The High-Fat Diet Based on Extra-Virgin Olive Oil Causes Dysbiosis Linked to Colorectal Cancer Prevention. Nutrients, 12(6), 1705.

Torres-Collado, L., García-de la Hera, M., Lopes, C., Compañ-Gabucio, L. M., Oncina-Cánovas, A., Notario-Barandiaran, L., González-Palacios, S., & Vioque, J. (2022). Olive oil consumption and all-cause, cardiovascular and cancer mortality in an adult Mediterranean population in Spain. Frontiers in Nutrition, 9, 997975.

Tsolaki, M., Lazarou, E., Kozori, M., Petridou, N., Tabakis, I., Lazarou, I., Karakota, M., Saoulidis, I., Melliou, E., & Magiatis, P. (2020). A randomized clinical trial of Greek high phenolic early harvest extra virgin olive oil in mild cognitive impairment: The MICOIL pilot study. Journal of Alzheimer's Disease, 78(2), 801-817.

Xia, M., Zhong, Y., Peng, Y., & Qian, C. (2022). Olive oil consumption and risk of cardiovascular disease and all-cause mortality: A meta-analysis of prospective cohort studies. Frontiers in Nutrition, 9, 1041203.