What is the most abundant source of flavonoids in most people's diets?

November 16, 2025 •

4 min read

According to the National Institutes of Health, flavonoids are widely consumed by nearly all adults in the U.S., but often in very low amounts. A specific type of flavonoid from a common beverage accounts for the vast majority of intake, making it the most abundant source of flavonoids in most people's diets.

Quick Summary

Tea is the most abundant source of flavonoids for most people, contributing a significant majority of the flavan-3-ol subclass to the average diet. The total intake of flavonoids is strongly influenced by the regular consumption of beverages like black and green tea.

Key Points

Tea is the most abundant source: Beverages like black and green tea are the single largest source of dietary flavonoids for many people, especially through the consumption of flavan-3-ols.
Flavan-3-ols dominate intake: This specific subclass of flavonoid found in tea accounts for a majority of the average person's total flavonoid intake.
Diverse intake is key: Consuming a variety of flavonoid-rich foods beyond just tea is associated with a wider range of health benefits and may be more protective against chronic disease.
Fruits and vegetables matter: While tea may provide the largest quantity, foods like berries, citrus fruits, onions, and kale provide diverse flavonoid subclasses that contribute to a healthy diet.
Cooking affects flavonoid content: The way you prepare food influences flavonoid levels, as some compounds can be lost during cooking, particularly when boiling vegetables.
Dark chocolate and wine also contribute: Other noteworthy sources of flavonoids include dark chocolate and red wine, which contain flavan-3-ols and anthocyanidins, respectively.

The Surprising Dominance of Tea in Flavonoid Intake

While many people associate flavonoids with colorful fruits and vegetables, epidemiological studies consistently show that tea is the single most abundant source of flavonoids in many Western diets. Specifically, black and green tea are packed with flavan-3-ols, a subclass of flavonoids that accounts for a massive percentage of total flavonoid consumption. While berries, apples, and citrus fruits are also excellent sources, the sheer volume of tea consumed by large populations makes it the top contributor by a wide margin.

The Flavan-3-ol Powerhouse

Flavan-3-ols are the most prevalent flavonoid subclass in many diets, and tea is the primary vehicle for their consumption. These compounds, which include catechins in green tea and theaflavins and thearubigins in black tea, are responsible for tea's potent antioxidant and anti-inflammatory properties. The fermentation process that creates black tea changes the structure of these compounds, but both green and black varieties remain exceptionally high in flavan-3-ols. This consistent, high intake from a regular beverage explains its dominance over foods that may be consumed less frequently or in smaller quantities.

Beyond the Brew: Other Significant Sources of Flavonoids

While tea dominates in total intake, a diverse range of plant-based foods is essential for getting a wide variety of flavonoid types. The six main classes of flavonoids—anthocyanidins, flavanones, flavones, flavonols, flavan-3-ols, and isoflavones—are all found in different foods. A broad diet rich in these plant-based foods can offer a wider spectrum of these beneficial compounds. Here is a brief breakdown of where to find other types of flavonoids:

Berries: Blueberries, blackberries, and strawberries are excellent sources of anthocyanidins, the pigments responsible for their vibrant colors.
Citrus Fruits: Oranges, lemons, and grapefruit are rich in flavanones like hesperidin and naringenin.
Onions and Kale: These vegetables provide high levels of flavonols such as quercetin and kaempferol.
Soy Products: Tofu and edamame are primary sources of isoflavones.
Herbs: Parsley and celery are good sources of flavones.

Why Dietary Diversity Matters for Flavonoids

It's important to remember that sheer quantity from one source isn't the whole story. Research indicates that consuming a wider diversity of flavonoid-rich foods, rather than just large amounts of a single type, may offer greater long-term health benefits. Different flavonoid subclasses have varying biological effects, and consuming a mix ensures a broader range of protective functions. This is why public health recommendations emphasize eating a wide variety of fruits and vegetables alongside other flavonoid sources.

Comparison of Common Flavonoid Sources


Food/Beverage	Primary Flavonoid Subclass	Contribution to Diet	Examples of Specific Flavonoids
Tea (Black & Green)	Flavan-3-ols (Catechins, Theaflavins)	Very High (Dominant source in many diets)	Catechin, Epicatechin, Theaflavins
Onions	Flavonols (Quercetin, Kaempferol)	Moderate to High (Common ingredient)	Quercetin, Kaempferol
Berries	Anthocyanidins	Moderate (Consumed frequently by some)	Cyanidin, Delphinidin, Malvidin
Citrus Fruits	Flavanones (Hesperidin, Naringenin)	Moderate (Often consumed as juice)	Hesperidin, Naringenin
Apples	Flavan-3-ols (Procyanidins), Flavonols (Quercetin)	Moderate (Popular fruit)	Quercetin, Procyanidins
Cocoa/Dark Chocolate	Flavan-3-ols (Catechins)	Lower (Smaller, less frequent portions)	Catechins, Epicatechins

The Impact of Food Processing

Another factor influencing your flavonoid intake is how food is prepared. Flavonoids are sensitive compounds, and their levels can change during cooking and processing. For instance, brewing tea in hot water releases a significant amount of its flavonoids. However, flavonoids in vegetables can be lost when cooked in water due to their solubility. Meanwhile, the flavonoids in citrus juice are different from those in the peel, affecting the final concentration. Understanding these factors helps in making better dietary choices to maximize your intake.

Conclusion: Prioritize the Power of Tea and Diverse Plants

In summary, while a variety of fruits and vegetables contain valuable flavonoids, tea, particularly black and green tea, represents the most abundant source for many people due to high intake of flavan-3-ols. Its regular consumption contributes a significant portion of daily flavonoid intake. However, for optimal health benefits, it's not just about quantity from a single source. Emphasizing a diverse diet rich in all plant-based foods, including berries, citrus, and leafy greens, ensures a broader spectrum of flavonoids with varied protective effects. For those seeking an easy and consistent way to boost their flavonoid consumption, a daily cup of tea is a simple and effective strategy.

One authoritative outbound link to a credible health source can be added here, such as a link to the NIH or a similar institution's flavonoid fact sheet. For a comprehensive list of flavonoid contents, you can reference the USDA's database.

Note: This article is for informational purposes only and does not constitute medical advice. Consult a healthcare professional for personalized health guidance.

Frequently Asked Questions

Both black and green tea are rich sources of flavonoids. Green tea contains high levels of catechins (a flavan-3-ol), while black tea has different but still abundant forms of flavan-3-ols called theaflavins and thearubigins, which are produced during fermentation.

Yes, nearly all fruits and vegetables contain some level of flavonoids. However, the specific type and concentration vary greatly. Colorful produce like berries, red cabbage, and spinach, as well as citrus fruits and onions, are particularly rich sources.

Fruit juice does contain flavonoids, but consuming whole fruit is generally better. Juicing can remove a lot of beneficial fiber, and the overall nutritional profile is less complete than in the whole food.

The six main classes of flavonoids are anthocyanidins, flavanones, flavones, flavonols, flavan-3-ols, and isoflavones. Each class is found in different types of plant-based foods.

Cooking methods can impact flavonoid content. Boiling vegetables in water can cause a significant loss of flavonoids due to their water solubility. Other methods like stir-frying or roasting with less liquid may help retain more of these compounds.

Flavonoids are a type of antioxidant, but they are not the only ones. They are a large group of plant compounds with potent antioxidant and anti-inflammatory properties, but other nutrients and compounds also act as antioxidants.

Tea is considered the most abundant source in many diets not necessarily because it has the highest concentration per gram, but because it is consumed much more frequently and in higher volumes than other high-flavonoid foods like berries or certain vegetables.