Polyphenols in Olive Oil: Health Benefits & What to Look for
by Nicola Lando
Polyphenols are natural antioxidant compounds found particularly in virgin and extra virgin olive oil. They contribute to EVOO's bitterness and peppery taste, help protect the oil against oxidation, and have been studied for their effects on human health.
Higher-polyphenol EVOOs often come from early-harvest olives and varieties such as Coratina, Picual and Koroneiki, although only laboratory testing can tell you an oil's actual polyphenol content.
In this guide, you'll learn about:
- What are Polyphenols in Olive Oil?
- What are the health benefits of polyphenols in extra virgin olive oil?
- Factors Affecting Polyphenol Levels in Olive Oil
- What is a High Polyphenol Count?
- What do polyphenols taste like?
- Which olive varieties have the highest polyphenol content?
- How to Choose Olive Oil with a High Polyphenol Content
- Can I use polyphenol-rich olive oil for frying?
- How should I store olive oil to preserve polyphenols?
- Are there specific brands known for high polyphenol olive oils?
- Which oils should I choose for high polyphenol count?
Why trust this guide?
Author, Nicola Lando is the founder of Sous Chef and a qualified olive oil sommelier, having graduated from ESAO in Spain. She also holds Imperial Executive Education’s certificate in Nutrition for Health: Evidence-Based Tools and Strategies.
Since starting Sous Chef, Nicola has tasted thousands of olive oils and, over the past decade, has worked directly with more than 50 extra virgin olive oil producers across Europe. Her experience spans sourcing, tasting, comparing cultivars, understanding harvest and production methods, and selecting oils for flavour, quality and everyday use.
You can browse our selection of high polyphenol extra virgin olive oils here.
What are Polyphenols in Olive Oil?
Polyphenols are naturally occurring plant compounds found in olives and retained in virgin and extra virgin olive oil.
They are best known for contributing to the bitterness, astringency and peppery sensation of fresh olive oil, while many of the grassy, fruity and herbal aromas come from separate volatile compounds.
Polyphenols also act as antioxidants within the oil itself, helping to slow oxidation and protect flavour and quality over time. This is one reason oils with a higher polyphenol content can be more resistant to deterioration.
So polyphenol content matters for two main reasons: flavour and stability. Higher-polyphenol oils are often more bitter and peppery, and their antioxidant compounds help protect the oil against oxidation.
Polyphenols are also the subject of a large body of research into the health effects of extra virgin olive oil, which we explore below.
Health Benefits of Polyphenols in Extra Virgin Olive Oil
TL;DR — the key benefits of polyhenols:
Help protect cholesterol from oxidative damage: olive-oil polyphenols help protect blood lipids, including LDL cholesterol, from oxidation — a process involved in the build-up of fatty plaques in arteries and the development of cardiovascular disease.
May help your body remove excess cholesterol: some human studies suggest polyphenol-rich olive oil can improve the function of HDL — the particles that help transport cholesterol away from tissues and back to the liver for disposal.
May help control inflammation: compounds in EVOO such as oleocanthal have demonstrated anti-inflammatory activity. Chronic inflammation is associated with many long-term health conditions, although research into exactly how much olive-oil polyphenols can influence this in humans is still developing.
EVOO gives you more than healthy fats alone: olive oil is naturally rich in oleic acid, a monounsaturated fat that can help maintain healthy cholesterol levels when it replaces saturated fat. Extra virgin olive oil also retains polyphenols, which are largely removed during refining — so you get both benefits in the same oil.
Extra virgin olive oil is unusual among cooking oils because it contains not only monounsaturated fat, principally oleic acid, but also naturally occurring polyphenols. These plant compounds act as antioxidants and are one of the main reasons high-quality EVOO is studied separately from refined olive oil.
The strongest evidence for olive-oil polyphenols relates to cardiovascular health and protection against oxidative stress.
Cardiovascular Health
One of the best-known studies is the EUROLIVE randomised controlled trial, published in the Annals of Internal Medicine. Researchers gave participants olive oils with low, medium and high polyphenol levels while keeping the oils otherwise similar. As polyphenol content increased, levels of oxidised LDL fell and HDL cholesterol rose modestly. This is important because oxidation of LDL is one of the processes involved in the development of atherosclerosis. (Annals of Internal Medicine / PubMed)
A later systematic review and meta-analysis of randomised controlled trials also found that higher-polyphenol olive oils reduced markers of oxidative stress, including oxidised LDL, compared with lower-polyphenol oils. (Food Science & Nutrition / PubMed)
This is also the basis of the authorised European health claim that olive-oil polyphenols contribute to the protection of blood lipids from oxidative stress, provided the oil contains sufficient amounts of specific polyphenols such as hydroxytyrosol and its derivatives.
Polyphenols and HDL Cholesterol
There is also evidence that olive-oil polyphenols may improve the function of HDL, rather than simply increasing the amount of HDL cholesterol in the blood.
In one randomised controlled trial, participants consuming a polyphenol-rich olive oil showed improved cholesterol efflux capacity — HDL's ability to remove cholesterol from cells and transport it back towards the liver for disposal. (Arteriosclerosis, Thrombosis, and Vascular Biology / PubMed)
However, not every trial has produced the same result. A more recent crossover study found no significant improvement in cholesterol-efflux capacity when comparing higher- and lower-polyphenol EVOOs, so this remains an active area of research rather than a settled health claim. (British Journal of Nutrition / PubMed)
Anti-Inflammatory Effects
Olive-oil polyphenols are also being studied for their effects on inflammation.
One of the best-known compounds is oleocanthal, which contributes to the distinctive peppery sensation at the back of the throat in some fresh EVOOs. Laboratory research has shown that oleocanthal can inhibit some of the same inflammatory enzymes targeted by anti-inflammatory medicines such as ibuprofen.
This does not mean olive oil works like taking an anti-inflammatory drug, but it helps explain why researchers are interested in the relationship between EVOO, inflammation and long-term health.
What Does the Research Mean in Practice?
The evidence is strongest for cardiovascular benefits and protection of blood lipids from oxidative damage.
There is also promising research into inflammation, HDL function, cognitive health and other areas, but it is important not to overstate the findings. Many of these effects are still being investigated, and some evidence comes from small human studies or laboratory research rather than large long-term clinical trials.
What we can say with confidence is that choosing a fresh, well-made extra virgin olive oil gives you two things at once:
Oleic acid, a monounsaturated fat that can help maintain healthy cholesterol levels when it replaces saturated fat in the diet.
Polyphenols, antioxidant compounds found in much greater quantities in virgin and extra virgin olive oils than in refined olive oils.
A 2023 systematic review of randomised controlled trials concluded that olive-oil polyphenols may have beneficial effects on lipid metabolism, particularly HDL cholesterol, although the size of the effect depends on the polyphenol dose and the individual study. (PubMed)
So while polyphenols are not a magic ingredient, they are one of the clearest reasons to choose a fresh, high-quality extra virgin olive oil rather than a refined olive oil.
Factors Affecting Polyphenol Levels in Olive Oil
Polyphenol levels in olive oil can vary enormously, even between oils from the same country or region. The final count depends on the olive itself, when it was harvested, how it was processed and how the oil has been stored.
1. Olive Variety
Some olive cultivars naturally produce oils with higher levels of phenolic compounds than others. Coratina, Picual, Koroneiki and Moraiolo are all known for producing particularly robust, polyphenol-rich oils.
Variety is only one factor, though. Two oils made from the same olive can still have very different polyphenol levels depending on harvest timing, climate and processing.
2. Harvest Timing
Olives harvested earlier in the season, while still green, generally contain more polyphenols than fully ripe fruit.
Early-harvest oils often have a more pronounced bitter and peppery character, although this varies by olive variety and producer. Read our guide to new-harvest olive oils.
3. Climate and Growing Conditions
Temperature, rainfall, irrigation and growing conditions can all influence the phenolic content of olives.
There is no single region that automatically produces the highest-polyphenol olive oil: variety, season and farming conditions all interact.
4. Milling and Processing
What happens after the olives are picked matters enormously.
How quickly they reach the mill, the crushing and malaxation conditions, temperature, oxygen exposure and filtration can all affect how many polyphenols remain in the finished oil.
For this reason, “cold pressed” or “traditionally pressed” is not on its own a guarantee of a high polyphenol count. Prompt milling and careful extraction are more important indicators of quality.
5. Age and Storage
Polyphenols naturally diminish as olive oil ages.
Exposure to light, heat and oxygen accelerates this process, which is why fresh oil stored in dark glass, tins or other light-protective packaging will generally retain its quality better than oil exposed to heat or bright light.
What is a High Polyphenol Count?
There isn't one universally regulated definition of “high-polyphenol olive oil”. You will often see 250mg/kg used as a benchmark. This derives from the EU-authorised health claim for olive-oil polyphenols, which requires a daily 20g serving of oil to provide at least 5mg of hydroxytyrosol and its derivatives.
However, total-polyphenol results can vary according to the laboratory method used, so numbers from different producers are not always directly comparable.
Is 500mg/kg polyphenols high?
In practical terms, an EVOO reporting around 500mg/kg total polyphenols would generally be regarded as extremely polyphenol-rich. However, the analytical method, storage and how long ago the oil was harvested also matter.
What do polyphenols taste like?
Polyphenols are particularly responsible for the bitterness and peppery, sometimes throat-catching sensation in fresh extra virgin olive oil. Oleocanthal is strongly associated with that distinctive peppery catch at the back of the throat.
The grassy, tomato-leaf, artichoke, apple and herbal aromas of great olive oil come largely from a separate family of volatile aroma compounds, rather than polyphenols.
So a bitter or peppery EVOO can be a useful clue that phenolic compounds are present — but taste alone cannot tell you its polyphenol count.
And we sometimes see high polyphenol counts in very 'smooth' EVOOs with not so much kick!
Which olive varieites have the highest polyphenol content?
Polyphenol count starts with the olive variety.
Some varities can never achieve a high polyphenol count, however early the harvest, or careful the processing is. These are some varities known for their potential for productin high polyphenol olive oils.
| Variety | Typical character | Polyphenol tendency |
|---|---|---|
| Coratina | Intensely bitter, green and peppery | Often capable of very high levels |
| Picual | Green, robust, tomato leaf/herbal | Often high; also highly oxidation-resistant |
| Koroneiki | Herbaceous, fruity, peppery | Often produces phenolic early-harvest oils |
| Cerasuola | Grassy, fruity, balanced bitterness and pepper | Can achieve substantial levels without being extremely aggressive |
How to Choose Olive Oil with a High Polyphenol Content
If you specifically want an olive oil with a high polyphenol content, the most useful thing to look for is an actual laboratory polyphenol result, usually shown in mg/kg.
At Sous Chef, we've added the measured polyphenol count post harvest, on each extra virgin olive oil product page. Or go direct to our selection of high polyphenol extra virgin olive oils here.
If that information is not available, these are the next best clues to polyphenol levels:
Choose extra virgin olive oil. EVOO is mechanically extracted and retains far more of the olive’s natural phenolic compounds than refined olive oil.
Look for a recent harvest date. Polyphenol levels fall over time, so fresher oil will generally retain more of its original phenolic content.
Consider early-harvest or new-season oils. Green olives usually contain more polyphenols than fully ripe fruit.
Look at the olive variety. Coratina, Picual, Koroneiki and Moraiolo are among the varieties associated with high-polyphenol oils.
Check the packaging. Tins, dark glass and opaque containers help protect olive oil from light, which accelerates oxidation and polyphenol loss.
Use taste as a clue, not a measurement. Bitterness, astringency and a peppery sensation at the back of the throat can indicate the presence of phenolic compounds, but taste cannot tell you the actual polyphenol count.
If you're comparing oils, the strongest evidence is always a recent lab result alongside the harvest date.
To know more on how to use and cook with extra virgin olive oil, read our guide here.
Can I use polyphenol-rich olive oil for frying?
Yes. Extra virgin olive oil is suitable for frying as well as sautéing and roasting. Heating will progressively reduce some of its phenolic compounds, particularly during prolonged or repeated high-temperature frying, but EVOO's predominantly monounsaturated fatty-acid profile and natural antioxidants make it relatively resistant to oxidation.
From a practical point of view, I use a very good everyday EVOO for frying - it's easier to just keep one bottle on the counter.
From a practical point of view, I use a very good everyday EVOO for frying - it's easier to just keep one bottle on the counter. But save the most expensive, intensely flavoured early-harvest oils for drizzling over dishes, where it'd break the bank to even use a few tablespoons in a frying pan.
How should I store olive oil to preserve polyphenols?
Store olive oil in a cool, dark place, away from light and heat.
Contact with oxygen also makes a difference. A half empty bottle of olive oil will oxidise more quickly than a full bottle. Therefore when you open a bottle, you want to keep using it, rather than switching between several different bottles.
Are there specific brands known for high polyphenol olive oils?
Look for trusted producers who focus on quality and transparency.
At Sous Chef southern Italian producers, Frantoio Muraglia, Galantino and Olio Guglielmi consistently have oils over 550mg/kg.
Which high polyphenol olive oils should I buy?
You can browse Sous Chef's selection of high polyphenol extra virgin olive oils. Here are a few highlights below.
This extra virgin olive oil sneaks into the high polyphenol category with +250mg/kg. It isn't as high as some of the other oils, due to the olive variety. However, its processing is phenomenal from one of the best producers in Sicily, and this outstanding EVOO is like a party in your mouth!
From Greece, Honest Toil's koroneiki olive oils are famed for their rounded, smooth flavour. You'll find they have less of the peppery kick than some of the Southern Italian oils, but still with excellent polyphenol ratings. These are all high polyphenol olive oils.
With more than 500mg/kg, this is another very high polyphenol extra virgin olive oil. It is made from cold-pressed Coratina olives – a variety native to the Apulia region of Italy. Coratina olives contain three times more polyphenols than any other Italian olive variety. This gives the oil its intense flavour, with spicy notes and hints of astringency.
If you prefer your olive oil in something long lasting that you can refill for years to come, choose that same Coratina oil from Muraglia, but in a hand-painted terracotta bottle. Again +500mg/kg of polyphenols.
This is an early harvest oil, with another whopping+500mg/kg polyphenol , Olio Guglielmi IGP Puglia oil is an extra virgin olive oil - vivid green, with a golden hue. It is made from olives which are cold-pressed immediately after the harvest to preserve their flavour and polyphenols.
With an ultra-high polyphenol count of +750mg/kg Guglielmi’s Fior D’O extra virgin olive oil is a fresh, unfiltered oil made from the first olives harvested in October. It has a vivid green-gold colour and the unmistakable taste of freshly pressed olives. It stands out from other extra virgin olive oils thanks to its creamy consistency and well-balanced flavour.
Shop the finest quality extra virgin olive oils, or read how to choose the best olive oil in the UK.
You can browse our selection of high polyphenol extra virgin olive oils here.
About the author
Nicola Lando is the co-founder and CEO of Sous Chef, where she has spent more than a decade sourcing, tasting and selecting specialist ingredients, cookware and tableware from producers around the world.
She trained at Leiths and later completed a stage at a Michelin-starred London restaurant, experiences that helped shape Sous Chef’s original mission: to give home cooks access to the same exceptional ingredients used by professional chefs.
Today, Nicola leads much of Sous Chef’s product sourcing and ingredient selection, working directly with producers and travelling internationally to food fairs, farms, mills and manufacturers. She tastes thousands of products each year and has built deep expertise across storecupboard ingredients, olive oil, condiments, spices, preserved foods and specialist cooking ingredients.
She holds an olive oil sommelier certification from ESAO in Spain, Imperial Executive Education’s Certificate in Nutrition for Health: Evidence-Based Tools and Strategies certificate; as well as studying Food Safety and Control at University of Greenwich.
Nicola also writes recipes and ingredient guides for Sous Chef, combining practical cooking experience with first-hand knowledge from producers, suppliers and specialist food makers. Her work focuses on helping cooks understand how to choose better ingredients, use them well, and get more flavour from their cooking.
