Neither, mostly. Olive oil does not look inflammatory. But a 2026 meta-analysis of 20 trials found that diets rich in its main fat did not change CRP or other inflammation markers. A small calming signal shows up only with polyphenol-rich extra virgin oil, and that evidence is still shaky.
Is olive oil inflammatory or anti-inflammatory?
Start with what's in the bottle. Most of olive oil is one fat, oleic acid. The rest is a small amount of plant compounds called polyphenols, which give good extra virgin oil its peppery bite in the back of your throat.
A 2026 meta-analysis (a study that pools the results of many trials) went after the fat. It gathered 20 randomized trials with 1,009 adults, published between 1991 and 2023. Each one compared a diet high in oleic acid with a diet low in it. Most trials kept calories the same on both diets, so the only real change was the type of fat.
The result was flat. The oleic-rich diets did not change CRP (C-reactive protein, a blood marker your liver makes when inflammation is up). They also did not move IL-6 or TNF-alpha, two signals immune cells use to turn inflammation on. The authors called these diets "metabolically neutral" for inflammation, weight and blood pressure.
There was one small surprise. Waists grew by 0.63 cm on average, less than a quarter of an inch. The authors think that is likely too small to matter and may be short-term.
So olive oil is not inflammatory. That's the good news. The fat alone also doesn't seem to cool things down.
Other reviews landed in the same place
This is not one review going against the crowd. A 2024 meta-analysis pooled 33 trials of extra virgin olive oil with 2,020 people. It found no significant effect on CRP, IL-6, IL-10 or TNF-alpha. It did find lower insulin levels, which is worth knowing, but it is a different story.
In 20 trials, diets rich in olive oil's main fat left CRP and IL-6 unchanged.From a 2026 meta-analysis in J Health Popul Nutr
Another 2024 review looked at 14 olive oil trials in healthy and at-risk adults. It found no change in CRP across 8 trials that measured it.
Not every review agrees. A 2020 review of trials concluded that regular olive oil lowered inflammation markers, especially IL-6. Even those authors said more research is needed, comparing olive oil with other fats.
Does extra virgin olive oil reduce inflammation?
Here is where it gets interesting. When researchers stop asking "olive oil or not?" and ask "which olive oil?", a signal appears.
A 2026 meta-analysis pooled 23 randomized trials with 1,138 people who used extra virgin olive oil every day. In trials that compared oils high in polyphenols with oils low in them, the high-polyphenol oils lowered CRP by 0.99 mg/L. That's a real-sized change. But the trials disagreed with each other a lot, and the certainty of the evidence ranged from moderate to very low.
An earlier review of 26 studies found the same pattern for other heart-related markers. Compared with low-polyphenol olive oil, high-polyphenol oil improved oxidized LDL, a damaged form of "bad" cholesterol. Smaller analyses in that review also reported better inflammation markers.
That's why we grade this Emerging. The fat is neutral. The polyphenols might help, and they're the part to watch.
The company olive oil keeps
Olive oil rarely shows up alone. In the Mediterranean diet it sits next to vegetables, beans, fish and nuts. A 2025 meta-analysis of 16 trials compared a Mediterranean diet with added olive oil against a low-fat diet. The Mediterranean diet improved inflammation and blood vessel markers. That tests the whole pattern, though, not the oil by itself.
Large cohort studies point the same way. A 2024 review of 30 cohort studies, covering more than two and a half million people, linked higher olive oil intake to lower risk of heart disease and of dying early. Each extra 10 grams a day was linked to 8% lower risk of death overall. No link was found with cancer. These studies watch people over time, so they show a link, not proof. People who use more olive oil may also eat and live differently.
What this means for you
Tick what you'll try this week. Your picks stay on this device.
you have been told to limit fat or calories for a medical reason, you have gallbladder or pancreas problems, or you are trying to bring down a high CRP result (oil alone is unlikely to do it).
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The bottom line
Twenty trials of oleic-rich diets, 33 of extra virgin oil, and another 14 in healthy adults kept landing on the same flat line for CRP. The fat in olive oil is not inflammatory, and it isn't a fire extinguisher either. What's left is a quieter clue in the polyphenols, plus decades of cohort data on people who cook this way. So pour it on your vegetables instead of using butter, choose the peppery kind when you can, and let the rest of the plate do its share.
Common questions
Does olive oil reduce inflammation in the body?
Not by much, on current evidence. A 2026 meta-analysis of 20 trials found diets rich in olive oil's main fat did not change CRP, IL-6 or TNF-alpha. A 2024 review of 33 extra virgin olive oil trials also found no change in CRP or IL-6. The exception: polyphenol-rich oils lowered CRP compared with low-polyphenol oils, though the evidence is low certainty.
Is olive oil inflammatory when heated?
We found no trials that measured inflammation markers after people ate heated olive oil. The closest is one small trial in 20 people with obesity, who ate breakfasts made with oils that had been heated through 20 frying cycles. Virgin olive oil led to less oxidative stress after the meal than sunflower oil. That's related to inflammation. It isn't the same thing.
How much olive oil a day for inflammation?
No dose has been shown to lower inflammation markers. For long-term health, cohort studies linked each extra 10 grams a day to 7% lower risk of heart disease. The benefit leveled off at about 18 grams a day for heart disease and 22 grams for overall death risk. That's roughly one to one and a half tablespoons.
Is extra virgin olive oil better than regular olive oil?
Possibly. Extra virgin oil keeps more polyphenols. In trials comparing high- and low-polyphenol olive oils, the high-polyphenol oils lowered CRP by 0.99 mg/L. They also improved oxidized LDL. The evidence is mixed, and certainty ranged from moderate to very low.
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How this article was made
Researched and written from 9 peer-reviewed papers. Our automated check matched every claim against the exact words of its source, confirmed every paper exists in PubMed, and found none retracted. Checked October 30, 2026. Not individually reviewed by a doctor. Photos are illustrative; the people in them are not patients or readers.
Grades run Strong, Moderate, Emerging, Early and Not supported, and the grade decides the words we may use. How we grade evidence · Medical disclaimer
Sources
- Meta-analysisThe effect of diets enriched with high-oleic sources on anthropometric, inflammatory, and blood pressure outcomes: a systematic review and meta-analysis.Zhang W, Chen X, Sohouli MH J Health Popul Nutr, 2026.PubMedFull paper
- Meta-analysisEffect of Extra Virgin Olive Oil on Anthropometric Indices, Inflammatory and Cardiometabolic Markers: a Systematic Review and Meta-Analysis of Randomized Clinical Trials.Morvaridzadeh M, Cohen AA, Heshmati J et al. J Nutr, 2024.PubMedFull paper
- Meta-analysisSupplementation of Olive Oil and Flaxseed Oil on Blood Pressure and Inflammation in Healthy and At-Risk Adults: A Systematic Literature Review and Meta-Analysis.McNabb TB, Young I, Newman RG et al. Curr Hypertens Rev, 2024.PubMedFull paper
- Meta-analysisEffects of daily extra virgin olive oil consumption on biomarkers of inflammation and oxidative stress: a systematic review and meta-analysis.Vidal Damasceno J, Garcez A, Anelo Alves A et al. Crit Rev Food Sci Nutr, 2026.PubMedFull paper
- Meta-analysisThe effect of high-polyphenol extra virgin olive oil on cardiovascular risk factors: A systematic review and meta-analysis.George ES, Marshall S, Mayr HL et al. Crit Rev Food Sci Nutr, 2019.PubMedFull paper
- Meta-analysisIs olive oil good for you? A systematic review and meta-analysis on anti-inflammatory benefits from regular dietary intake.Fernandes J, Fialho M, Santos R et al. Nutrition, 2020.PubMedFull paper
- Meta-analysisEffect of the Mediterranean Diet Supplemented With Olive Oil Versus the Low-Fat Diet on Serum Inflammatory and Endothelial Indexes Among Adults: A Systematic Review and Meta-analysis of Clinical Controlled Trials.Pourrajab B, Fotros D, Asghari P et al. Nutr Rev, 2025.PubMedFull paper
- Meta-analysisOlive oil intake and cardiovascular disease, cancer, and all-cause mortality: a systematic review and dose-response meta-analysis of prospective cohort studies.Ke Y, Fan H, Zhao Y et al. Food Funct, 2024.PubMedFull paper
- Randomized trialThe antioxidants in oils heated at frying temperature, whether natural or added, could protect against postprandial oxidative stress in obese people.Perez-Herrera A, Rangel-Zuñiga OA, Delgado-Lista J et al. Food Chem, 2013.PubMedFull paper
