Polyphenols: Top Health Benefits, Supplements and Food Sources

If you’re looking for a natural way to improve your overall health, polyphenols may be the answer. Known as powerful antioxidants, polyphenols are compounds found in plants that can help protect our cells from damage and have been linked to numerous health benefits. From helping reduce inflammation and cholesterol levels to providing cancer-fighting properties, there is a great wealth of research showing just how beneficial these plant nutrients can be. 

In this article, we’ll take an in-depth look at what makes up these amazing molecules and explore some of the top foods and supplements that offer high concentrations of polyphenols.

What Are Polyphenols?

Polyphenols are a diverse group of naturally occurring compounds found primarily in plant-based foods, including fruits, vegetables, legumes, whole grains, nuts, seeds, and certain beverages like tea and red wine. They are secondary metabolites, meaning that they are not essential for a plant’s growth and development, but they play a crucial role in protecting the plant from environmental stressors such as UV radiation, pests, and disease. They are of particular interest to humans as they possess many important health benefits, some of which are unique to the class of compounds.

Polyphenols can be divided into 4 categories:

Flavonoids

Flavonoids represent the largest and most diverse group of polyphenols, with over 6,000 identified compounds. Flavonoids are responsible for the vivid colors of many fruits and vegetables and are known to possess strong antioxidant and anti-inflammatory properties. They can be found in various foods, such as onions, apples, berries, citrus fruits, tea, red wine, and dark chocolate. 

Stilbenes

These are a smaller group of polyphenols, with resveratrol being the most well-known compound within this category. Resveratrol is primarily found in red wine, grapes, and some berries. It has gained significant attention due to its potential anti-aging, anti-cancer, and cardio-protective effects. Stilbenes are known to possess antioxidant, anti-inflammatory, and anti-microbial properties, and may help protect against neurodegenerative diseases.

Lignans

Lignans are a group of polyphenols derived from the cell walls of plants, especially in seeds, whole grains, and some vegetables. Lignans are considered phytoestrogens, as they can interact with estrogen receptors in the body and exhibit both estrogenic and antiestrogenic effects. 

Phenolic acids

These are another significant group of polyphenols and are found in various plant-based foods, with coffee being the most significant source of phenolic acids in the average diet. Other sources include tea, berries, whole grains, and leaves of certain fruits and vegetables. 

Health Benefits of Polyphenols

Reduced Inflammation

Polyphenols possess anti-inflammatory properties, which can help alleviate chronic inflammation [1], a key contributor to chronic disease. They modulate inflammatory pathways and inhibit pro-inflammatory cytokines, reducing inflammation and promoting overall health.

Antioxidants

Polyphenols are potent antioxidants, neutralizing free radicals that cause oxidative stress and cellular damage. By scavenging these reactive molecules, polyphenols help protect the body from the harmful effects of oxidative stress, thereby reducing the risk of chronic diseases.

Enhanced Metabolism

Some polyphenols such as the catechins in green tea have been shown to positively impact metabolism [2], increasing fat oxidation and energy expenditure, which can contribute to better weight management and overall health.

Promotes Tissue Repair

Plant polyphenols can promote tissue repair by reducing inflammation and supporting the regeneration of damaged cells, contributing to improved recovery and healing [3]. This may be particularly useful to sports nutrition or athletes seeking to optimize recovery.

Healthier Skin

Polyphenols can protect the skin from damage caused by UV radiation, oxidative stress, and inflammation, promoting a healthier and more youthful appearance [4].

Gut Health

Polyphenols can positively influence gut microbiota composition, promoting the growth of beneficial bacteria while inhibiting the growth of harmful bacteria [5]. This supports overall gut health and can impact immune system function, metabolism, and mental health.

Blood Sugar Support

Polyphenols have been shown to improve insulin sensitivity, regulate glucose metabolism, and lower risk of type 2 diabetes by supporting healthy blood sugar levels and reducing inflammation that leads to insulin resistance [6].

Eye, Brain, and Heart Health

Polyphenols can promote eye health by protecting retinal cells from oxidative stress, support brain health by reducing neuroinflammation and promoting neuronal survival [7], possibly slowing the worsening of Alzheimer’s disease progression, and enhance heart health by improving endothelial function, reducing blood pressure, and decreasing the risk of cardiovascular disease.

Anti-Aging

Polyphenols may have anti-aging effects on the brain(8) and body by reducing oxidative stress, inflammation, and cellular damage, as well as supporting DNA repair and maintaining telomere length, which can contribute to a longer and healthier lifespan.

Can You Get Polyphenols Through Your Diet Alone?

Polyphenols can be obtained through your diet alone by consuming a variety of plant-based foods rich in these compounds. In fact, obtaining polyphenols from polyphenol-rich foods is the most natural and effective way to incorporate them into your daily intake. To ensure a sufficient supply of polyphenols, aim to include a wide range of fruits, vegetables, whole grains, legumes, nuts, seeds, and beverages like tea and red wine in your diet.

However, most people struggle to consume enough plant-based foods in order to get ample amounts of polyphenols, which makes polyphenol supplementation a very helpful adjuvant.

What Foods Are Rich in Polyphenols?

The following are excellent sources of polyphenols: 

• Berries: Blueberries, strawberries, raspberries, and blackberries.
• Cocoa: Dark chocolate and natural cocoa powder [9].
• Coffee: Freshly brewed coffee, preferably from whole beans.
• Tea: Green tea, black tea, and white tea.
• Spices: Cloves, cinnamon, turmeric, and ginger.
• Nuts: Walnuts, almonds, hazelnuts, and pistachios.
• Seeds: Flaxseeds, chia seeds, and sunflower seeds.
• Red wine: Preferably made from high-polyphenol grape varieties like Pinot Noir or Cabernet Sauvignon.
• Olives: Whole olives, black or green, in brine or oil.
• Olive oil: Extra virgin olive oil, cold pressed and unrefined [10].
• Vegetables: Spinach, kale, artichokes, and red cabbage.
• Soy: Edamame, tofu, and tempeh.
• Whole grains: Quinoa, oats, barley, and whole wheat.

What Are the Best Polyphenol Supplements?

Red Powders

Similar to green powders, red powders are typically made from a blend of polyphenol-rich berries, fruits, and sometimes vegetables. These supplements are designed to provide a concentrated source of polyphenols and other nutrients, such as vitamins and minerals, and can be added to smoothies, juices, or water.

Resveratrol

Resveratrol is a polyphenol found primarily in red wine, grapes, and some berries. It has gained attention for its potential anti-aging, anti-cancer, and cardio-protective properties [11]. Resveratrol supplements are available in capsule or tablet form and may help support heart health, metabolism, and cognitive function.

Curcumin

Curcumin is the active compound in turmeric, a popular spice known for its potent anti-inflammatory and antioxidant properties. Curcumin supplements may help reduce inflammation, alleviate pain, and provide significant improvements in symptoms of depression and anxiety [12]. They often include an absorption-enhancing ingredient, like black pepper extract, to increase bioavailability.

Green Tea Extract

Green tea extract is derived from green tea leaves and contains concentrated amounts of polyphenols, particularly catechins like EGCG. These supplements may support weight management, metabolism, and heart health, as well as provide antioxidant and anti-inflammatory benefits.

Astragalus

Astragalus is a traditional Chinese herb known for its immune-boosting and anti-inflammatory properties. Astragalus supplements contain various polyphenols and other bioactive compounds, which may help improve immune function [13], support cardiovascular health and reduce inflammation.

Ginger Extract

Ginger is a spice with powerful anti-inflammatory and antioxidant properties. Ginger extract supplements may help alleviate nausea, reduce inflammation, and provide relief from pain caused by conditions like arthritis.

Ginkgo Biloba Extract

Ginkgo biloba is a tree native to China, and its leaves contain a unique combination of polyphenols. Ginkgo biloba extract supplements have been used to support cognitive function [14], memory, and circulation, as well as provide antioxidant and anti-inflammatory benefits.

Grape Seed Extract

Very helpful in reducing markers of overall oxidation thanks to high antioxidant content.

What to Look for When Choosing Your Polyphenol Supplement

High-quality ingredients: Look for supplements that use pure, high-quality, and preferably organic ingredients. This ensures that the product is free of contaminants, such as pesticides or heavy metals, and provides many potential benefits.

Professionally-formulated blends: Opt for supplements that have been formulated by qualified professionals, such as nutritionists or herbalists. This ensures the product contains a high polyphenol content and other beneficial compounds at an appropriately recommended dose.

For red powders: Seek products that contain a diverse range of polyphenol-rich ingredients, such as berries, fruits, and vegetables. Additionally, look for a blend that includes other superfood compounds and ingredients, like vitamins, minerals, and antioxidants, to provide a comprehensive nutritional profile.

Trustworthy manufacturers: Choose supplements from reputable manufacturers with a proven track record of producing high-quality products. Look for companies that are transparent about their sourcing, manufacturing processes, and quality control measures.

Third-party quality testing: Select products that have undergone independent third-party testing for quality, potency, and purity. This ensures that the supplement meets the label claims and is free of contaminants.

What to Avoid:

Low-quality ingredients: Steer clear of supplements that use low-quality, synthetic, or non-organic ingredients, as these may be less effective and potentially harmful.

Ineffective blends: Avoid products that do not provide a balanced blend of polyphenols and other beneficial compounds, or that contain insufficient dosages of key ingredients. Also stay clear of a proprietary blend.

Fillers: Stay away from supplements that contain unnecessary fillers, binders, or artificial additives, as these may dilute the potency of the product or cause adverse reactions.

Sketchy manufacturers: Be cautious of products from unknown or unverified manufacturers, as their products may not meet quality standards or be accurately labeled.

Lack of quality oversight: Avoid supplements that do not provide any information about their quality control measures or third-party testing, as this may indicate a lack of transparency and accountability.

Are There Any Risks or Side Effects from Taking Polyphenols Supplements?

Polyphenols are naturally occurring compounds found in various plant-based foods such as fruits, vegetables, nuts, seeds, and teas. And while they are generally considered safe, taking polyphenol supplements may have some increased risk or side effects. These may include:

Allergic reactions: Some individuals may be allergic or sensitive to certain polyphenols or specific ingredients in the supplements.

Medication interactions: Polyphenols may interact with certain medications, such as blood thinners, blood pressure medications, or chemotherapy drugs. Consult with your healthcare provider before taking polyphenol supplements if you are on any medications.

Gastrointestinal issues: High doses of polyphenol supplements may cause temporary gastrointestinal side effects like bloating, gas, or diarrhea in some individuals.

Use in specific populations: Safety is not established in pregnant or lactating women and children under the age of 18.

Will Polyphenol Supplements Work for Me?

The effectiveness of polyphenol dietary supplements can vary from person to person, depending on several factors such as individual genetics, overall healthy diet, and lifestyle. While some studies suggest that polyphenols may have health promoting properties, such as antioxidant, anti-inflammatory, and cardioprotective effects, large-scale studies that take into account these differences would be necessary to guarantee their effectiveness.

Polyphenols: In Conclusion

All in all, polyphenols can be a wonderful addition to any diet as they offer an array of important health benefits. It is possible to get your daily intake through dietary sources alone, but if you have any concerns about not getting enough through food, there are some excellent quality polyphenol supplements available on the market. 

For optimum results, always look for supplements that use high-quality and all-natural ingredients, with minimal processing. Additionally, it is highly recommended that you consult your medical professional about starting a supplement routine and identify potential allergies and known drug interactions associated with specific compounds in certain polyphenol supplements. 

With properly managed supplementation and adequate care in choosing the right products for yourself, incorporating polyphenols into your diet can bring incredible health benefits without causing any unwanted side effects.

References

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[2] Rondanelli, M., Gasparri, C., Perna, S., Petrangolini, G., Allegrini, P., Fazia, T., Bernardinelli, L., Cavioni, A., Mansueto, F., Oberto, L., Patelli, Z., Tartara, A., & Riva, A. (2022). A 60-Day Green Tea Extract Supplementation Counteracts the Dysfunction of Adipose Tissue in Overweight Post-Menopausal and Class I Obese Women. Nutrients, 14(24), 5209. https://doi.org/10.3390/nu14245209

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