Polyphenols rarely appear on food labels or in nutrition guidelines, but they're attracting growing attention from researchers because of the role they play in protecting our long-term health and creating long lived people.
But what exactly are polyphenols, and perhaps most importantly, which foods contain the highest amounts? Let’s take a look…
What are polyphenols?
Polyphenols are naturally occurring compounds produced by plants. They help protect the plants against environmental stresses such as UV radiation, insects, and disease, but when we eat those plants, they also benefit our own health.
Polyphenols – like vitamins - are tiny and measured in milligrams – ie 1/1000th of a gram. They represent an equally tiny fraction of any given fruit, vegetable or herb.
Much of the interest in polyphenols comes from their antioxidant and anti-inflammatory properties. Research has linked long-term diets rich in plant polyphenols with a lower risk of many chronic diseases, including cardiovascular disease, type 2 diabetes, osteoporosis, certain cancers, and neurodegenerative conditions.
Scientists believe these compounds help reduce oxidative stress, limit inflammation, and support normal cell function throughout the body.
Polyphenols also have a direct impact on our gut's good bacteria by acting as pre-biotics – and according to a 2022 study2 could, via the gut brain axis, help to prevent neurodegenerative diseases, external such as Alzheimer's.
In summary, they are vital to health – so how can you get more polyphenols into your everyday diet?
Top polyphenol-containing foods
Researchers have identified several hundred different polyphenols in edible plants, and they fall into a number of different groups, including flavonoids, phenolic acids, lignans, and stilbenes. Each behaves slightly differently within the body, so variety is the key.
Here’s some of the top foods to eat to boost polyphenols:
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Curly kale: around 60-120 mg of quercetin per serving
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Blueberries: approximately 35-75 mg of peonidin per serving
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Blackberries: around 100 mg of cyanidin per serving
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Blackcurrants: roughly 130 mg of pelargonidin per ounce
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Red cabbage: around 50 mg of malvidin per serving
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Green beans: approximately 2-10 mg of myricetin per serving
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Red peppers: around 0.5-1 mg of luteolin per serving
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Red wine: approximately 8-20 mg of epicatechin per serving.
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Extra virgin olive oil: around 5-8 mg of oleuropein per tablespoon.
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Dark (70%) chocolate: around 50 mg of flavanols per 10 grams – mainly catechins
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Herbs: including cloves, rosemary, thyme, oregano, turmeric
Source: https://www.sciencedirect.com/science/article/pii/S0002916522039144
Notice anything?
That’s right. Almost every food on that list is bursting with colour.
That's because many polyphenols are the natural pigments responsible for the deep reds, rich purples, vibrant greens, and dark blues we see in fruits and vegetables.
Anthocyanins, for example, create the striking colours found in blueberries, blackberries, blackcurrants, aubergines, and red cabbage, while other polyphenols contribute to the shades found in leafy greens, beans, and other vibrant foods.
That’s just one reason why it’s important to eat foods with different colours.
And why the advice to “eat the rainbow” has become so popular. Different colours often indicate different polyphenols, antioxidants, vitamins, and minerals, so eating a wide variety of colourful foods gives you access to a broader range of plant compounds than relying on the same handful of vegetables.
It's also one of the defining characteristics of the Mediterranean diet. Meals are naturally built around colourful fruits, vegetables, and herbs - along with moderate amounts of red wine - creating an eating pattern that's naturally rich in many different polyphenols rather than focusing on just one specific source.
Although Extra Virgin Olive Oil is not as brightly coloured as some others on our list, it should have a special place on your table. A recent scientific review1 confirmed it contained polyphenols with “.. potent therapeutic effects against a series of chronic diseases, such as cardiovascular diseases, diabetes, neurodegenerative disorders and cancer”.
Olive oil helps keep the linings of your arteries clear and supple, improving blood and nutrient flow. The sharp flavour at the back of your throat indicates the presence of polyphenols. Replace saturated fats (butter and margarine) with olive oil to improve blood cholesterol levels and reduce cardiovascular risk.
A tip: polyphenols are found in all parts of plants, especially the outer layers.
So, don’t throw away vegetable peelings, cut them up turn them into crisps.
You can reduce food waste and increase your polyphenol (and fibre) intake by using cauliflower stalks in cauliflower cheese.
If you're making mash, keep the polyphenol and vitamin C rich potato skins and oven-roast them with sea salt and olive oil until they are a crisp snack.
Western European’s polyphenol average intake less than Mediterranean countries.
It's perhaps no surprise, then, that studies have found large differences in polyphenol intake between countries. In Northern Europe and the USA, beverages like coffee and tea contribute a high proportion. Whereas populations following a Mediterranean-style diet get a greater proportion of their polyphenol intake from sources like fruits, vegetables, nuts, and olive oil.
How many polyphenols do I need?
Combining numerous research sources suggests you should aim for about 1,000mg of polyphenols a day of which perhaps 750mg should be from fruits, vegetables and herbs.
It’s tempting to simply choose whichever foods contain the highest quantity of polyphenols, but nutrition isn't quite that straightforward. The number of polyphenols in a food is only part of the picture. What matters just as much is bioavailability; how much of those compounds your body can actually absorb and use.
Factors such as the chemical structure of the polyphenol, the way it's attached to other molecules, the food it's eaten with, and even your own gut bacteria all influence how much eventually reaches the bloodstream and is ultimately able to benefit your body.
This means the polyphenols that appear in the highest quantities aren't always the ones that have the greatest effect inside the body. Some are absorbed easily, while others are extensively broken down by the digestive system or eliminated before they can be used. For example, the bioavailability of rutin is estimated to be just 15-20% that of quercetin, despite both belonging to the same flavonoid family.
Researchers have also found that some polyphenols are unlikely to be absorbed efficiently from whole foods in their natural form. This is one reason why supplements continue to be studied, with some evidence suggesting that higher blood concentrations may be achieved from supplements containing polyphenols.
The supplement featured below provides 161 plant colour nutrients (largely polyphenols) from 750mg per day of Mediterranean plant extracts.
For most people the best advice is simple: Rather than chasing individual compounds or specific foods, or obsessing over milligram values per serving, focus on getting a wide variety of colourful plant foods every day, whether that comes from fresh foods or supplements.
That's what following a Mediterranean diet plan encourages, and it's why it continues to be associated with so many long-term health benefits.
Part of a Series
This article is part of series on staying healthy as you get older and improving your quality of life. It’s not only a goal almost everyone shares, but has huge implications on national healthcare spending, productivity and economic resilience.
It strongly recommends the Mediterranean diet as the best way of eating but recognises that maintaining strength and aerobic fitness is also a critical part of a healthy ageing lifestyle.
It also suggests a supplement to help reach the increased plant nutrient levels that you need as you get older.
DailyColours® contains 161 plant nutrients – nutrients that are missing from an ordinary vitamin and mineral pill. Clinical trials show that it offers Mediterranean diet benefits in a daily supplement. You can see it here.
Note: The content on this site is intended for general wellness and informational purposes only. It is not personalized medical advice. Consult a healthcare professional before making any changes to your diet, exercise, or lifestyle routines.