Ever heard of them?
Brimming with health benefits, they are a group of chemicals found in fruits, vegetables and plants. As antioxidants, they possess a variety of disease-fighting qualities–from cancer prevention to reduction of cardiovascular disease risk.
More popularly, they are the reason behind the story that ‘dark chocolate’ and ‘red wine’ are good for you.
So what’s the real truth—the real power behind polyphenols?
Together, let’s take a closer look.
What Exactly ARE Polyphenols?
Simply stated, polyphenols are naturally occurring compounds that give plants color and protect them from disease and other environmental threats and/or help them recover from injury. They’re a type of phytochemical found in plant foods like spices, fruits and vegetables, seeds and legumes.
In recent years, they’ve gained popularity as the study of polyphenols has uncovered their antioxidant properties and their potential protective and/or curative effect on chronic and life-threatening human diseases.
There are four different classes of polyphenols:
- Phenolic acids: derivatives of benzoic and cinnamic acid and found abundantly in plant foods.
- Stilbenes: usually synthesized in plants only due to infection or injury, they are less commonly found in the diet.
- Lignans: diphenolic compounds, some of which are considered phytoestrogens.
- Flavonoids: divided into six classes, they can be found in a wide variety of plant foods.
The Fabulous Flavonoid…
When it comes to polyphenols, it is the flavonoid class which reigns king. So while approximately 8,000 polyphenolic compounds have been discovered in plant foods, over 4,000 of those are in the well-studied flavonoid group!
One of the best things about flavonoids is that they are (for the most part) what give plants and flowers and berries and vegetables their beautiful, brilliant colors. But besides being pretty to look at, they’re the most famous of the antioxidants because of their potential health benefits.
The flavonoid group is so huge that it’s broken into six sub-classes.
- Flavonols: Found mostly in the skin of fruits and vegetables, the main function of this group is to provide UV protection to the plant. Flavonols have been studied for their ability to increase blood flow and reduce cholesterol in the bloodstream.
- Flavones: Found in yellow and green fruits and vegetables, these chemical compounds are believed to relax constricted blood vessels.
- Flavanones: Known for their interaction with vitamin C, they may reduce the risk of heart disease and have anti-inflammatory properties.
- Flavanols: Not to be confused with flavOnols, you might also hear this group called catechins. They have many of the same benefits as their similarly named group member, and there is also evidence that flavanols might play a role in preventing and/or treating dementia.
- Anthocyanins: These unique compounds give red, blue and purple plants their color. (Aside: they’re also responsible for the red in fall leaves!) They have been linked to lower risk of heart disease and stroke and might inhibit tumor growth or development.
- Isoflavones: Similar in chemical composition to estrogens, these polyphenols can balance estrogen levels in the body. Not only can they increase low levels, they can impede high estrogen levels, which have been linked to weight gain and breast cancer.
Where’s the Best Place to Find Polyphenols?
So where can we find polyphenols? Which foods are the best sources?
As a rule of thumb, seasonings are the richest source of polyphenols, followed by seeds, fruits and vegetables. Cocoa is also a rich source, but don’t reach for that chocolate bar. It will deliver a lot of calories along with those polyphenols and you can get a lot more antioxidant activity from other foods that aren’t so high in saturated fat.
For a definitive directory of polyphenols—including the foods in which they’re found and their antioxidant rank–check this list of the 100 richest sources.
Why Polyphenols Keep Us Healthy
Plants use various chemical compounds to protect their own health. And when you consume these compounds, you protect your health, lowering your risk of chronic and debilitating conditions including type 2 diabetes, cancer, heart disease and neurodegenerative disease. Polyphenols help you fight against the following:
- Diabetes: Tea catechins and other polyphenols have been studied for anti-diabetic potential. They may inhibit the absorption of glucose in the gut.
- Cancer: Polyphenols may offer protection from stomach, colon, liver, lung and breast cancers among others, reducing the number and/or size of tumors. Polyphenols like resveratrol and quercetin are currently under study for their protective effects against cancer and anti-aging properties.
- Cardiovascular Disease: Consuming a diet rich in plant foods has been shown to reduce the instance of cardiovascular disease. The polyphenols inhibit LDL oxidation, a key mechanism in atherosclerosis, and they seem to have anti-platelet and anti-inflammatory effects as well.
- Alzheimer’s: Studies found that polyphenols from fruits and vegetables might play an important role in delaying the onset of Alzheimer’s disease. And green tea has been linked to a reduced risk of developing Parkinson’s disease.
- Lung Disease: It’s also believed that dietary polyphenols might protect against obstructive lung diseases such as asthma.
- Osteoporosis: There is growing evidence that polyphenols can also help slow down the loss of bone mineral density that leads to osteoporosis.
And the best part about polyphenols? Unlike chemical drugs prescribed to treat chronic, life-threatening diseases, there are NO known adverse effects to eating plant foods!
What About Red Wine and Chocolate?
Probably two of the most famous polyphenols (even though you might not know them by name) are resveratrol (rez-VEER-a-troll), and quercetin (KWUR-se-tin). Stilbene resveratrol and flavonoid catechin and quercetin are prevalent in foods like grapes, red wine, green tea, apples, berries, peaches and cocoa/chocolate…their presence is at the origin of the idea that ‘dark chocolate and red wine’ are good for you.
However there are probably better ways to get the power of polyphenols working for you. For example, the cocoa in chocolates will get you a dose of polyphenols but it will also deliver a lot of calories; you can receive the same benefits from a long list of plant-based foods that aren’t so high in total and saturated fat. Red wine is the same; you can just as easily get the benefits from simply eating the original grape itself.
This ‘red wine and dark chocolate is good for you’ hype has been eagerly misinterpreted by many to mean that you can simply eat what you want all day and then drink a couple of glasses of red wine or eat a few pieces of dark chocolate at night and ‘make everything all right’. It doesn’t work this way.
One Last Big Tip…
It is super important to remember that there is no ONE polyphenol that assures good health; you will get different benefits from different polyphenols. Therefore the best strategy (as always) is to eat a wide variety of polyphenol-rich foods that will be found naturally in a whole food plant-based diet.
These organic compounds – all of the components in plant foods – work together.
Eating different foods with different types and concentrations of compounds with a wide variety of antioxidant activity is the key to getting the results you’re looking for.
Just by simply eating a color-rich diet of whole, plant foods, you will never have to worry about getting enough polyphenols; you will naturally be ingesting plenty of them as well as receiving all of their considerable health benefits.
Polyphenols. One more reason a whole food plant-based diet makes infinite sense.