Key Takeaways Polyphenols are antioxidant-rich compounds found in tea, coffee, cocoa, nuts and berries Folks who consume these foods and drinks may be helping their hearts, new research shows The study tracked adults' polyphenol intake and heart health for 11 years MONDAY, Dec.1, 2025 (HealthDay News) — Tea, coffee, berries, cocoa, nuts, whole grains, olive oil: They’re all rich in antioxidant compounds called polyphenols, and they’re all good for your heart, a new British study shows.