Quick answer: Polyphenols (also called phenols or phenolic compounds) are natural antioxidants found in extra virgin olive oil. They give fresh oil its bitter and peppery taste. Refined olive oil has very few because refining removes them. The amount varies a lot from oil to oil: it is highest in fresh oil pressed from greener, early-harvest olives and falls as the oil ages. The EU allows a health claim only for olive oils with at least 5 mg of hydroxytyrosol and its derivatives per 20 g of oil.
“High polyphenol” is now printed on many premium bottles. But what are polyphenols, how much does an ordinary extra virgin olive oil contain, and what actually raises or lowers them?
This guide explains the basics in plain language, sticks to what the research and the regulators actually say, and shows how to choose and keep an oil so you get the most from it.
In this guide
What are olive oil polyphenols?
Polyphenols are a large family of plant compounds. Olives make them to protect themselves, and some pass into the oil when the fruit is crushed. The best known in olive oil are:
- Hydroxytyrosol and tyrosol, and the larger molecules they are bound in (such as oleuropein and ligstroside derivatives).
- Oleocanthal, which causes the peppery sting in the throat. A 2005 study in Nature found it has an anti-inflammatory action similar to ibuprofen in laboratory tests. That is a lab finding, not a reason to use olive oil as a medicine.
- Oleacein, a close relative of oleocanthal and one of the main bitter compounds.
Because these compounds are bitter and pungent, a fresh, high-phenol oil is usually easy to recognise by taste. See how to taste olive oil.
Which olive oils contain the most?
| Type of oil | Refined? | Polyphenols |
|---|---|---|
| Extra virgin olive oil | No | Highest; varies widely between oils |
| Virgin olive oil | No | Medium |
| Olive oil (pure / classic / light) | Mostly refined | Low |
| Pomace olive oil | Refined, solvent extracted | Very low |
Refining uses heat and filtering to remove flavour defects, and it removes most of the polyphenols at the same time. That is the main reason extra virgin olive oil is the grade worth paying for. Compare the grades in types of olive oil and pomace olive oil.
What the EU health claim says
The European Union allows only one health claim about olive oil polyphenols, in Regulation (EU) No 432/2012:
- The wording: olive oil polyphenols contribute to the protection of blood lipids from oxidative stress.
- It may be used only for an olive oil that contains at least 5 mg of hydroxytyrosol and its derivatives per 20 g of oil.
- The label must explain that the benefit comes from a daily intake of 20 g (about 1.5 tablespoons) of that olive oil.
Not every extra virgin olive oil reaches this level, and measuring it needs a laboratory. EU-funded researchers have noted that agreeing on a simple, standard test has been a challenge. So treat any “high polyphenol” claim on a label as meaningful only if the seller can show a lab result.
For the wider evidence on olive oil and health, read our olive oil benefits guide, which separates strong evidence from weak claims.
What raises or lowers polyphenols
| Factor | Effect |
|---|---|
| Olive ripeness at harvest | Greener, earlier-harvest olives give more bitter, pungent, phenol-rich oil. As olives ripen, the oil becomes milder. |
| Olive variety | Some varieties are naturally much richer in phenols than others. |
| Time from picking to pressing | Bruised or stored olives start to ferment and oxidise. Pressing the same day keeps quality higher. |
| Processing temperature | Extraction without added heat protects the delicate compounds. See cold pressed vs extra virgin. |
| Refining | Removes most polyphenols. |
| Light, heat and air after bottling | Polyphenols slowly break down as they protect the oil from oxidation. Old or badly stored oil has less. |
How to get more polyphenols from your oil
- Buy extra virgin, not “pure” or “light”.
- Check the harvest date and choose the most recent harvest you can find.
- Choose dark glass or a tin, never clear plastic on a bright shelf.
- Use an opened bottle within a few weeks to a couple of months, and close the cap after each use. Our guide on how to store olive oil explains why.
- Taste it. A clear bitterness and a peppery finish are good everyday signs of a fresh, phenol-rich oil.
- Use some of it raw, on salads, daal, hummus or bread. Cooking is fine too; see cooking with extra virgin olive oil.
Our extra virgin olive oil
We pick our olives by hand in September and October and press them on the same day, without heat or chemicals, which helps keep the natural polyphenols in the oil. We do not currently print a polyphenol figure on our label, because that needs a lab test for each harvest. Nothing is blended in. See 1 litre, 750 ml, 500 ml or 250 ml.
Browse more topics in the olive oil guide.
Frequently asked questions
What are polyphenols in olive oil?
They are natural antioxidant compounds from the olive fruit, such as hydroxytyrosol, tyrosol, oleocanthal and oleacein. They give fresh extra virgin olive oil its bitter and peppery taste.
Does extra virgin olive oil have more polyphenols than regular olive oil?
Yes. Regular or light olive oil is mostly refined, and refining removes most polyphenols. Extra virgin olive oil is unrefined, so it keeps them.
What does high polyphenol olive oil mean?
There is no single legal definition. The EU health claim needs at least 5 mg of hydroxytyrosol and its derivatives per 20 g of oil, so a high polyphenol label is most meaningful when backed by a lab test.
Does cooking destroy olive oil polyphenols?
Heat reduces them over time, so some are lost in cooking, but extra virgin olive oil still keeps more than refined oils. Using some oil raw gives you the full amount.
How can I tell if my olive oil is high in polyphenols?
Without a lab test you cannot know the exact figure, but clear bitterness and a peppery sting in the throat are good signs of a fresh, phenol-rich oil.
Sources
- Commission Regulation (EU) No 432/2012, list of permitted health claims (EUR-Lex)
- CORDIS (European Commission): a cheap and simple test to verify olive oil health claims
- International Olive Council: COI/T.20/Doc. No 15, sensory analysis of olive oil, method for the organoleptic assessment of virgin olive oil (Rev. 11, 2024)
- International Olive Council: designations and definitions of olive oils
- Beauchamp et al., 2005, Nature 437: 45-46, ibuprofen-like activity in extra-virgin olive oil (summary)