Olive oil polyphenols & cardiovascular health (3/3)
You learned in the previous blogs about cardiovascular health that strokes among people under 50 in the Netherlands have increased by 50% over the past decade, but that up to 80% of these strokes can be prevented through a healthy diet and regular physical activity. Neurologists frequently recommend the consumption of extra virgin olive oil, the main fat source of the Mediterranean diet. The polyphenols (such as such as hydroxytyrosol, oleuropein and oleocanthal) in extra virgin olive oil are the plant-based compounds that protect your cardiovascular health.
Drawing on a 2025 Wageningen University & Research report, commissioned by the Olive Oil Club, blog 1/3 and blog 2/3 on polyphenols and cardiovascular health outline that olive oil polyphenols protect your cardiovascular health by:
1. Preventing the oxidation of LDL cholesterol (“bad” cholesterol), a process that leads to artery-clogging atherosclerosis. For this effect, you should daily consume extra virgin olive oil that contains >250 mg/kg hydroxytyrosol, a specific olive oil polyphenol.
2. Reducing low-grade inflammation in your arteries that leads to atherosclerosis. For the optimal effect, the research shows that you need to consume extra virgin olive oil daily with >180 mg/kg oleocanthal, a specific olive oil polyphenol.
3. Improve your cholesterol profile, one of the key indicators to assess the level of risk of getting a stroke. For the optimal effect, the research shows that you need to consume extra virgin olive oil daily with >350 mg/kg polyphenols in total.
This blog post dives into the last two ways in which polyphenols in extra virgin olive oil protect your cardiovascular health.
The fourth way in which polyphenols in extra virgin olive oil protect your cardiovascular health is by lowering blood pressure and improving endothelial function.
Your blood vessels contain a thin layer called the endothelium. Think of it as an elastic layer that allows blood to flow easily through your vessels, and in this way helps regulate blood pressure. When this layer becomes stiff or damaged due to inflammation, it leads to endothelial dysfunction, one of the first steps toward heart disease and stroke. The endothelium also produces nitric oxide, a natural compound that helps your arteries relax and stay flexible. When endothelial function worsens, arteries stiffen, and blood pressure rises. This increases the risk of heart attacks or strokes.
Many scientific studies show that the polyphenols in extra virgin olive oil, especially hydroxytyrosol and oleuropein, help improve endothelial function and reduce blood pressure. They do this by enhancing nitric oxide availability, reducing oxidative stress, and lowering inflammation in blood vessels (Widmer et al., 2013; Moreno-Luna et al., 2012; MartĂn-Peláez et al., 2017; Ikonomidis et al., 2023; Correia et al., 2025; George et al., 2019).
In the study by Moreno-Luna et al. (2012), young women with mild hypertension consumed high-polyphenol olive oil for 2 months. Their systolic blood pressure dropped by 7.9 mmHg and diastolic by 6.6 mmHg—a clinically meaningful reduction—and their endothelial function improved.
In another double-blind trial with 30 patients with chronic coronary artery syndrome, those receiving olive oil rich in hydroxytyrosol for 1 month had significant improvements in arterial elasticity and endothelial function, while their levels of inflammatory and oxidative markers dropped (Ikonomidis et al., 2023).
MartĂn-Peláez et al. (2017) found that participants consuming high-phenolic olive oil (366 mg/kg) for 3 weeks had reduced systolic blood pressure and lower levels of inflammatory markers (IL8RA).
These findings are consistent with a meta-analysis of five human trials (145 participants) that showed olive oil polyphenols reduced systolic and diastolic blood pressure (Correia et al., 2025). A systematic review of 30 randomized control trials by Schwingshackl et al. (2015) further confirmed that polyphenol-rich olive oil improves endothelial function. Together, these studies show that daily consumption of extra virgin olive oil rich in polyphenols (>350 mg/kg total polyphenols) can support healthy blood pressure and keep your arteries flexible and strong. All olive oils from the Olive Oil Club contain much higher total polyphenol levels, implying that these olive oils can support your endothelial function and help you to keep a healthy blood pressure.
The fifth way in in which polyphenols in extra virgin olive oil protect your cardiovascular health is by improving glucose metabolism and protecting blood vessels from metabolic damage
Your heart and blood vessels are deeply connected to how your body manages sugar. When you eat, your blood sugar naturally rises. To keep it balanced, your body releases insulin, a hormone that helps move sugar from your blood into your cells for energy. But when you eat too much ultra-processed food or sugary snacks, or when your body becomes resistant to insulin, your blood sugar remains high. This condition, called insulin resistance, puts stress on your blood vessels and increases your risk of developing type 2 diabetes and cardiovascular disease.
Chronic high blood sugar damages your endothelium, causes inflammation, and makes it easier for fats to build up inside your arteries, leading to atherosclerosis, heart diseases, and strokes. This is why doctors consider diabetes one of the biggest risk factors for cardiovascular diseases.
Several studies show that specific olive oil polyphenols, particularly hydroxytyrosol and oleuropein, help regulate blood sugar levels and improve insulin sensitivity. These effects, in turn, protect your heart and blood vessels.
In a study by Jemai et al. (2009), diabetic rats that were given olive oil polyphenols showed a drop in blood glucose levels and better antioxidant activity, helping to protect both metabolism and arteries. This is supported by the study by Cao et al. (2013) that found that hydroxytyrosol reduced oxidative stress in obese mice, lowering the damage caused by high blood sugar. The study concluded that hydroxytyrosol-rich olive oil is associated with antidiabetic effects.
In human research, Santangelo et al. (2016) showed that people with type 2 diabetes who consumed high-polyphenol olive oil experienced lower blood sugar and reduced levels of inflammatory markers, all indicators of healthier metabolism and blood vessel function.
A clinical trial by Patti et al. (2020) confirmed similar effects for oleocanthal-rich olive oil, showing reductions in harmful cytokines such as IL-6, IL-17A, and TNF-α, while increasing anti-inflammatory ones like IL-10.
These studies together show that olive oil polyphenols help your body respond better to insulin, reduce oxidative stress, and prevent metabolic inflammation, three major steps in protecting your arteries from damage caused by high blood sugar.
The researchers from Wageningen University & Research concluded that the antidiabetic and metabolic-regulating effects of olive oil polyphenols are a key reason why people who follow the Mediterranean diet have lower rates of heart attacks and strokes. By improving your body’s ability to control sugar and inflammation, polyphenols keep your blood vessels flexible and healthy.
To experience this benefit, you should consume high-polyphenol extra virgin olive oil, ideally containing more than 300 mg/kg total polyphenols, including high levels of hydroxytyrosol, oleuropein, and oleocanthal. The olive oils selected by the Olive Oil Club contain even higher levels, ensuring your heart and blood vessels receive the full protective effect.
References:
Cao, K., Xu, J., Zou, X., Li, Y., Chen, C., Zheng, A., Li, H., Li, H., Szeto, I. M., Shi, Y., Long, J., Liu, J., & Feng, Z. (2013). Hydroxytyrosol prevents diet-induced metabolic syndrome and attenuates mitochondrial abnormalities in obese mice. Free Radical Biology And Medicine, 67, 396–407.
Correia, M., Gomes, A. T., Moreira, I., El Maghariki, J., Mendes, K., Correia, M. J., & Gomes, A. M. (2025). Unraveling the Extra Virgin Olive Oil Effect on Inflammation and on Gut and Saliva Microbiota. Biomolecules, 15(3), 338.
George, E. S., Marshall, S., Mayr, H. L., Trakman, G. L., Tatucu-Babet, O. A., Lassemillante, A. M., Bramley, A., Reddy, A. J., Forsyth, A., Tierney, A. C., Thomas, C. J., Itsiopoulos, C., & Marx, W. (2019). The effect of high-polyphenol extra virgin olive oil on cardiovascular risk factors: A systematic review and meta-analysis. Crit Rev Food Sci Nutr, 59(17), 2772-2795.
Ikonomidis, I., Katogiannis, K., Chania, C., Iakovis, N., Tsoumani, M., Christodoulou, A., Brinia, E., Pavlidis, G., Thymis, J., Tsilivarakis, D., Kountouri, A., Korakas, E., Lambadiari, V., Triposkiadis, F., Skaltsounis, L., Tseti, I., Iliodromitis, E. K., & Andreadou, I. (2023). Association of hydroxytyrosol enriched olive oil with vascular function in chronic coronary disease. Eur J Clin Invest, 53(7), e13983.
Jemai, H., Feki, A. E., & Sayadi, S. (2009). Antidiabetic and Antioxidant Effects of Hydroxytyrosol and Oleuropein from Olive Leaves in Alloxan-Diabetic Rats. Journal Of Agricultural And Food Chemistry, 57(19), 8798–8804
MartĂn-Peláez, S., Castañer, O., Konstantinidou, V., Subirana, I., Muñoz-Aguayo, D., Blanchart, G., Gaixas, S., de la Torre, R., FarrĂ©, M., Sáez, G. T., Nyyssönen, K., Zunft, H. J., Covas, M. I., & FitĂł, M. (2017). Effect of olive oil phenolic compounds on the expression of blood pressure-related genes in healthy individuals. Eur J Nutr, 56(2), 663-670.
Moreno-Luna, R., Muñoz-Hernandez, R., Miranda, M. L., Costa, A. F., Jimenez-Jimenez, L., Vallejo-Vaz, A. J., Muriana, F. J., Villar, J., & Stiefel, P. (2012). Olive oil polyphenols decrease blood pressure and improve endothelial function in young women with mild hypertension. Am J Hypertens, 25(12), 1299-1304.
Patti, A. M., Carruba, G., Cicero, A. F. G., Banach, M., Nikolic, D., Giglio, R. V., Terranova, A., Soresi, M., Giannitrapani, L., Montalto, G., Stoian, A. P., Banerjee, Y., Rizvi, A. A., Toth, P. P., & Rizzo, M. (2020). Daily Use of Extra Virgin Olive Oil with High Oleocanthal Concentration Reduced Body Weight, Waist Circumference, Alanine Transaminase, Inflammatory Cytokines and Hepatic Steatosis in Subjects with the Metabolic Syndrome: A 2-Month Intervention Study. Metabolites, 10(10), 392.
Santangelo, C., Filesi, C., Varì, R., Scazzocchio, B., Filardi, T., Fogliano, V., D’Archivio, M., Giovannini, C., Lenzi, A., Morano, S., & Masella, R. (2016). Consumption of extra-virgin olive oil rich in phenolic compounds improves metabolic control in patients with type 2 diabetes mellitus: a possible involvement of reduced levels of circulating visfatin. Journal Of Endocrinological Investigation, 39(11), 1295–1301.
Schwingshackl, L., Christoph, M., & Hoffmann, G. (2015). Effects of Olive Oil on Markers of Inflammation and Endothelial Function-A Systematic Review and Meta-Analysis. Nutrients, 7(9), 7651-7675.
Widmer, R. J., Freund, M. A., Flammer, A. J., Sexton, J., Lennon, R., Romani, A., Mulinacci, N., Vinceri, F. F., Lerman, L. O., & Lerman, A. (2013). Beneficial effects of polyphenol-rich olive oil in patients with early atherosclerosis. Eur J Nutr, 52(3), 1223-1231.
