5 top polyphenol benefits + 100 of the best food & drink sources

Polyphenols come from plants and offer an array of health benefits. Find out all about how polyphenols work, 5 top benefits of including them in your diet and 100 of the best food and drink sources.

What are polyphenols?

Polyphenols are a type of micronutrient found in plant foods like fruits, vegetables, wholegrains red wine, dark chocolate, tea, spices and herbs.

They are potent antioxidants, which are important for health as they can help reduce the oxidative damage caused by harmful free radicals in the body.^1,2

There are over 8000 different types of them, each with their own linked health benefits and uses. They can be categorised into the following subgroups:

Flavonoids

Over 4000 of 8000 known polyphenols are classified as flavonoids.³

Flavonoids can be broken down into these main types⁴:

• Flavones
• Flavonols
• Flavan-3-ols
• Flavanones
• Isoflavones
• Anthocyanidins

You can find them in all sorts of plant-based foods and whole grains. These foods are particularly rich in flavonoids:

• Berries
• Onions
• Red cabbage
• Kale
• Parsley
• Soya beans
• Dark chocolate
• Citrus fruits
• Red wine

Phenolic acids

These non-flavonoid polyphenols can be divided into 2 main types, benzoic acid and cinnamic acid.

You can find them in lots of fruits, vegetables and whole grains, with the most potent sources being⁵:

• Berries
• Apples
• Cherries
• Citrus fruits
• Rice bran
• Mangoes
• Passion fruit
• Coffee
  
• Tea
• Kiwi fruit
• Wheat
• Corn
• Oat flours
  

Phenolic acids get absorbed through the intestinal tract walls and can be beneficial to human health due to their potent antioxidant content and their anti-inflammatory properties.⁶

Polyphenolic Amides

This subgroup of polyphenols is most well-known for giving chilli peppers their heat as compounds called capsaicinoids, as well as being the avenanthramides in oats.

They have been found to have strong anti-inflammatory and antioxidant properties.⁷

Summary

• There are over 8000 types of polyphenols
• They can be broken down into 3 main subgroups: flavonoids, phenolic acids and polyphenolic amides
• Each has their own unique benefits

The 5 top polyphenols benefits

Polyphenols have been linked to a number of health benefits. Here are 5 of the best.

1. May help maintain healthy blood sugar levels

Polyphenols may help you to control your blood sugar levels.

There is a growing body of evidence that suggests that some polyphenols could help reduce the likelihood of blood sugar spikes. This is partly because polyphenols may be able to prevent dietary starch breaking down into simple sugars, which spike blood sugar levels.⁸

Studies also suggest that some polyphenols may also help the body secrete insulin – the hormone that transports sugar from your blood to your cells in order to keep blood sugar levels stable.⁹

Summary

• Polyphenol could help control blood sugar spikes
• Polyphenol may help your body secrete insulin

2. May support your heart health

A diet rich in polyphenols is likely to be very healthy, with all those wholegrains, fruits and veggies. And as well as a healthy diet can support your cardiovascular system, so can the antioxidants that come with it.

Growing research suggests that the high levels of antioxidants in certain foods, like polyphenols, can reduce the risk of chronic inflammation.¹⁰ This unwanted inflammation can present itself in multiple ways in the body.

One type of chronic inflammation that usually underlies cardiovascular disease is called Atherosclerosis, which is a risk factor for heart disease.¹¹

A recent review into Atherosclerosis-related ischemic heart diseases and strokes found that polyphenol-rich diets tend to show antioxidant and anti-inflammatory properties that could help reduce the risk of several cardiovascular conditions.¹²

More clinical studies are needed to confirm their efficacy, however.¹³

Summary

• Polyphenols have antioxidant and anti-inflammatory properties that could support heart health

3. May help to prevent blood clots

Polyphenols may make you less likely to get a blood clot.

Blood clots occur when platelets of blood circulating around your bloodstream clump together. This usually happens when the body needs to prevent excess bleeding, e.g. when your body makes a scab when you cut yourself.

The problem is that sometimes the body can experience excess platelet aggregation and form blood clots. These blood clots are associated with negative health conditions like strokes, thrombosis and pulmonary embolisms.¹⁴

Studies have shown that polyphenols may help to reduce the body’s platelet aggregation process, which can help to prevent blood clots forming.¹⁵ However, more human-based clinical studies are needed to further investigate this process.

Summary

• Polyphenols could help reduce excessive platelet aggregation that causes blood clots

4. May support your digestive system

Polyphenols may help us maintain a healthy, balanced microbiome by helping ‘good’ bacteria to thrive while helping to defend us from the harmful ones.¹⁶

A healthy, balanced microbiome can have profoundly positive effects on almost all aspects of our health, from improved digestion and immunity, to better brain function.

Foods rich in polyphenols tend to also be rich in fibre, e.g. fruit, vegetables, and wholegrains. The fibre in these foods helps to fuel good bacteria in our bodies and promote better digestion.

On top of this, some polyphenols have been seen to help fight against harmful bacteria. One example of this is the research into green tea polyphenols and how they may be able to fend off harmful bacteria strains, including E. Coli, Salmonella and C. difficile.¹⁷

Summary

• Polyphenols could help promote ‘good’ bacteria and get rid of harmful bacteria
• Foods rich in polyphenols tend to be fibre-rich and good for digestion generally, e.g. fruit and vegetables

5. May support brain health

Polyphenols may help your brain to function healthily.

One systematic review into the effects of polyphenol-rich interventions on healthy young and middle-aged adults found positive results.¹⁸

The data showed that when healthy adults took an effective polyphenol supplement, they experienced improved cognitive function, including memory, learning skills and reaction times, as well as decreased mental fatigue.¹⁹

Summary

• Research suggests that polyphenols may promote good brain function, including improved memory, reaction times and learning skills

Where are polyphenols found?

There are tons of foods and drinks that are naturally rich in polyphenols, and you probably consume at least a few of them every day already.

Here’s a comprehensive list of 100 of the best food and drink sources of polyphenols. They have been ranked from 1-100 by their polyphenol content according to the Phenol-Explorer database, accessed by Clermont University, France.²⁰

100 of the best food and drink sources of polyphenols

Are there polyphenols in tea? What about dark chocolate? Find out here.²¹

Summary

• There are lots of different foods and drinks out there full to the brim with powerful polyphenols
• Including them in your diet shouldn’t be too hard, as a lot are seasonings, fruits, vegetables, soy products or cocoa products

To break it up a little for you here’s the top dietary sources put into ‘top 5s’ according to food category:

5 fruits highest in polyphenols

1. Black chokeberry
2. Black elderberry
3. Blueberries
4. Blackcurrants
5. Black olive

Anybody else see a theme here? The blacker the berry, the sweeter the juice comes to mind!

5 vegetables highest in polyphenols

1. Soya
2. Globe artichoke hearts
3. Red onions
4. Spinach
5. Shallots

5 nuts/seeds highest in polyphenols

1. Flaxseed
2. Chestnut
3. Hazelnut
4. Pecans
5. Almonds

5 herbs and spices highest in polyphenols

1. Cloves
   
2. Peppermint
3. Star anise
   
4. Oregano
   
5. Celery seed

5 ‘other foods and drinks’ highest in polyphenols

1. Cocoa powder
2. Dark chocolate
3. Black tea
   
4. Red wine
5. Green tea
   

Is coffee high in polyphenols?

Yes, it is! As you can see from the table above, coffee is ranked number 36 out of 100 for top polyphenol content.

According to our source, each 100ml of filtered coffee can provide you with 214mg of polyphenols – not bad eh?

Other drinks high in polyphenols include:

• #52 Black tea
• #53 Red wine
• #54 Green tea
• #59 Apple juice
• #60 Pomegranate juice
• #64 Blood orange juice
• #66 Grapefruit juice
• #69 Blond orange juice 
• #73 Lemon juice
• #87 Chocolate beverage with milk
• #90 Soy milk
• #91 Pumelo juice
• #99 White wine
• #100 Rosé wine

Summary

• Yes, coffee is high in polyphenols

Which olive oil is highest in polyphenols?

Extra-virgin olive oil has been granted #61 on the top 100 polyphenol list, and no other olive oil gets a mention, why is that?

When comparing extra-virgin olive oil to plain old regular olive oil, it’s the processing that they go through that makes them different.

Extra-virgin olive oil is given its fancy title because it is made from pure, cold-pressed olives. Other ‘regular’ olive oils are usually made up of a blend of both cold-pressed and heat-processed oils.

This is done to decrease costs of the oil, as well as reduce its aroma, flavour, colour and bitterness to make it easier to cook with.

This means that extra-virgin olive oil is more able to hold onto its important antioxidant and anti-inflammatory properties, which includes its polyphenol count.

So, if you want to enjoy the polyphenol content of your olive oil and other health benefits, opting for extra-virgin olive oil is advised.

Summary

• Extra-virgin olive oil is highest in polyphenols

What about polyphenol supplements?

Polyphenol supplements have been around for a while now, offering people the advantage of getting a quick, easy and consistent dose of polyphenols. But they do have some potential downfalls.

Polyphenol supplements may contain concentrated polyphenols, but they don’t contain the same nutrients, e.g. fibre, starch and other vitamins and minerals that polyphenol-rich foods do.

Taking away these extra benefits may affect the efficacy of the polyphenols, as they seem to work best combined with the other natural nutrients found in food. More research needs to be done to find out if isolated polyphenols are as effective as those found in polyphenol-rich foods.

What’s more, polyphenol supplements are not currently regulated, and many can contain super-high doses that you would never find in foods that naturally contain polyphenols. It’s currently unclear how safe or beneficial these high does are.

Summary

• Polyphenol-rich foods seem to be more beneficial than polyphenol supplements
• More research needs to be conducted to confirm their efficacy and safety

Are polyphenols bad for you?

Polyphenol-rich foods and drinks are safe and healthy for most people to consume.

However, as we mentioned above, polyphenol supplements are unregulated and come with exceptionally high doses of some polyphenols, which may have negative consequences.

The general consensus seems to be that foods and drinks naturally rich in polyphenols carry more benefits that taking a polyphenol supplement.

If you do want to take polyphenol supplements, please consult your doctor first to see if it is suitable for you.

Summary

• Polyphenol-rich foods tend to be safe and healthy for most people to consume

The final word

Foods high in polyphenols are some of the healthiest foods we can eat, e.g. fruits, vegetables and wholegrains.

The polyphenols themselves have various potential health benefits, including supporting heart health and a healthy digestion.

Try including as many polyphenol-rich foods into your diet as possible to enjoy the benefits.

Last updated: 9 April 2021