The polyphenols in olive oil are powerfully cardio-protective, antioxidant, and anti-inflammatory. Extra virgin olive oil (EVOO) has the highest polyphenol concentration, but there is variation between EVOO batches. To get the same level of polyphenols, is it better to consume more of an oil with a lower concentration or less of the more-concentrated oil? Recent research answered this question.
An August 2025 study by researchers in Greece tested the benefits of different polyphenol strengths in EVOO on fifty patients with hyperlipidemia and twenty healthy patients. Subjects were randomly divided into two groups. One group consumed the oil with the higher phenolic concentration and the other received the second oil.
Both oils improved the ratio of HDL (“good”) cholesterol to LDL (“bad”) cholesterol. However, the increase in HDL was greatest for the oil with the higher phenolic concentration and most marked in the hyperlipidemia patients compared to the healthy controls.
Olive oil, being full of lipids itself, affects blood lipid levels. Therefore, it is not surprising that the level of total blood lipids was higher for those who consumed more olive oil at the lower polyphenol concentration.
The conclusion was that the EVOO oil with the highest concentration of polyphenols had the greatest cardiovascular health benefits.
This study included hyperlipidemia patients because it is particularly relevant for them. “Hyperlipidemia” literally means abnormally high lipid levels in the blood, and these lipids include cholesterol and triglycerides. The condition brings an increased risk of plaque buildup in the arteries, which can lead to heart disease and stroke.
Many researchers, including George Moschonis, who was not involved in this study, have previously reported on the benefits of phenolic-rich EVOO. Olive Oil Times recently quoted Moschonis as saying that “high-phenolic extra virgin olive oil produces superior effects on endothelial function, HDL activity, and even small reductions in blood pressure compared with low-phenolic or refined varieties.” George Moschonis is a professor at the Department of Dietetics, Nutrition and Sport at La Trobe University in Australia.
References
Kourek, C., Makaris, E., Magiatis, P., et al. (2025). Effects of high-phenolic extra virgin olive oil (EVOO) on the lipid profile of patients with hyperlipidemia: A randomized clinical trial. Nutrition, 17(15), 2543.
DeAndreis, P. (2025, November 4). New research strengthens link between olive oil polyphenols and cardiovascular health. Olive Oil Times.