OPCs are condensed tannins found in grape seed, pine bark, and cocoa. Powerful antioxidants that strengthen capillary walls and improve endothelial function. and pine-bark-extract.md for the two primary OPC sources. The 'French Paradox' is partially OPC-mediated (red wine procyanidins). --- *Reviewed by the Dose AI Research Team and Clinical Advisory Board* *Last updated: 2026-04-06*
Reviewed by the Scan Dose Research Team and Clinical Advisory Board | Last updated:
Not medical advice. Based on published clinical research and systematic reviews.