Polyphenols

Plant compounds

What does Polyphenols do in your body?

Thousands of plant compounds (flavonoids, resveratrol, catechins) in tea, coffee, berries, cocoa and olive oil. Not essential nutrients.

What does Polyphenols do?

Many act as signaling molecules; much is transformed by gut bacteria. The 'antioxidant' story is simpler than reality.

Which foods contain Polyphenols?

Tea, coffee, berries, apples, cocoa, olive oil, legumes, herbs.

What is known and unknown about Polyphenols?

Diets rich in polyphenol-containing foods are associated with better health; high-dose antioxidant supplements have generally disappointed in trials.

Evidence & sources

• Large trials of antioxidant supplements such as beta-carotene and vitamin E have not shown protection against cancer or heart disease, and some showed harm. Evidence: strong. Known: Multiple large RCTs. Unknown: Whole foods are a different question. Source: NIH NCCIH, Antioxidant Supplements: What You Need To Know (Current revision).

Connected topics

• Blueberries
• Dark Chocolate
• Olive Oil
• Coffee
• Tea
• Gut Microbiome
• "Superfoods"
• Inflammation

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General education only, not medical advice. Drafted Oct 2026 · pending qualified expert review.