How Many Polyphenols Should Good Olive Oil Have?
Discover what polyphenol levels indicate a high quality olive oil. Learn what mg/kg means, how polyphenols in oils are tested, what levels to look for and how to choose the best oil for your needs.
How Many Polyphenols Should a Good Olive Oil Have?
If you've started looking for a high-quality extra virgin olive oil, you've probably come across the term polyphenols. But how many polyphenols should a good olive oil actually contain, and what do these numbers mean?
The truth is that not all olive oils are created equal. While many supermarket olive oils contain relatively low levels of beneficial polyphenols, premium early-harvest extra virgin olive oils can contain several times more.
In this guide, we'll explain what polyphenols are, how they are measured, and what levels you should look for when choosing a high-quality olive oil.
What Are Polyphenols?
Polyphenols are naturally occurring plant compounds found in olives. They contribute to many of the characteristics associated with premium extra virgin olive oil, including:
A peppery sensation at the back of the throat
Slight bitterness
Fresh, grassy flavours
Natural stability and shelf life
Polyphenols are also responsible for many of the health-related properties associated with extra virgin olive oil as part of a Mediterranean diet.
How Are Olive Oil Polyphenols Measured?
Polyphenol levels are typically measured in milligrams per kilogram (mg/kg).
This figure represents the total concentration of phenolic compounds present in the oil at the time of testing.
Factors that influence polyphenol content include:
Olive variety
Harvest timing
Climate and growing conditions
Milling techniques
Storage conditions
Early-harvest olives generally produce oils with significantly higher polyphenol levels than olives harvested later in the season.
What Is Considered a Good Polyphenol Level?
Although there is no official classification system, the following ranges provide a useful guide.
Under 150 mg/kg: Most standard supermarket olive oils fall into this category.
These oils can still be genuine extra virgin olive oils, but they typically contain relatively low levels of polyphenols and may have a milder flavour profile.
150–250 mg/kg: Above average. Oils at this level often have a fresher taste and greater complexity than standard supermarket products.
250–500 mg/kg: High Polyphenol. Many olive oil experts would consider this range to represent genuinely high-polyphenol olive oil.These oils often display noticeable pepperiness and bitterness, both of which are indicators of phenolic content.
500+ mg/kg: Ultra High Polyphenol. This is where premium early-harvest oils are typically found. Oils with polyphenol levels above 500 mg/kg are relatively uncommon and are often produced in limited quantities. Many of the world's most sought-after extra virgin olive oils fall into this category. Oils at this level are used in health studies so we recommend purchasing this type of extra virgin olive oil if you are looking to consume it as a functional food for for health benefits.
Is Higher Always Better?
Not necessarily. While polyphenol content is an important quality indicator, it should not be the only factor considered when choosing an olive oil.
A great olive oil should also offer:
Excellent flavour balance
Freshness
Low acidity
Organic certification or practices to limit exposure to agricultural toxins and chemicals
Reliable transparent 3rd party testing and traceability
Proper storage and handling
The best oils combine high polyphenol levels with exceptional taste. Also there has been no scientific evidence to suggest that over 600mg/kg provides any increase in health benefits. That said polyphenol levels can degrade over time and through the production process so you always know you will be consuming a high level if you opt higher and you can in theory consume less for the same health benefits and reduce the calorie intake associated with olive oil.
Why Do High Polyphenol Oils Taste Peppery?
One of the compounds found within olive oil polyphenols is oleocanthal.
Oleocanthal is largely responsible for the peppery sensation often felt at the back of the throat when tasting premium extra virgin olive oil.This sensation is sometimes referred to as the "one-cough" or "two-cough" effect among olive oil enthusiasts.If an olive oil causes a slight peppery burn in the throat, it is often a sign that it contains significant levels of beneficial phenolic compounds.
How Can You Tell if an Olive Oil Is High in Polyphenols?
Look for producers who publish 3rd party laboratory test results.
Reliable indicators include:
Polyphenol content (mg/kg)
Harvest date
Olive variety
Country of origin
Independent laboratory testing
Purchasing from a high polyphenol specialist website or store like www.earlyharvest.co.uk
Be cautious of vague marketing claims such as "high in polyphenols" or "rich in antioxidants" if no actual polyphenol figures are provided.
What Polyphenol Level Should You Aim For?
For everyday use, a polyphenol level above 250 mg/kg is generally a good benchmark. If you're specifically seeking premium early-harvest olive oil, many experts recommend choosing oils with polyphenol levels of 400 mg/kg or higher.
Ultimately, the best olive oil is one that combines:
High polyphenol content
Excellent flavour
Fresh harvest dates
Transparent testing
Our Recommended High Polyphenol Olive Oils
If you're looking for organic olive oils with verified polyphenol levels, see our guide to the highest-quality options currently available in the UK: Best High Polyphenol olive oils in the Uk