Compound Monograph
Proanthocyanidins
Proanthocyanidins are condensed tannins built from flavan-3-ol units, abundant in many fruits, seeds and barks.
Classification
Proanthocyanidins are polyphenol (condensed tannin), part of the phenolics class. Antioxidant compounds built around one or more phenol rings — the flavonoids, tannins, phenolic acids, coumarins, and pigments behind much of a plant's protective chemistry.
Where Does It Come From? (11)
Proanthocyanidins are naturally occurring polyphenol (condensed tannin), found in Ginkgo, Grape seed, Pine bark and 8 other sources. They are well tolerated orally (low toxicity).
Research & Evidence
Proanthocyanidins, also called condensed tannins, are oligomers and polymers built from flavan-3-ol units such as catechin and epicatechin. They are widespread in foods including grape seeds, cocoa, apples, berries and pine bark, and give many plant extracts their astringency. As dietary polyphenols they are studied extensively for antioxidant activity, cardiovascular and vascular effects, and—in the case of cranberry—a role in discouraging bacterial adhesion in the urinary tract.
Toxicity & Safety
Proanthocyanidins from common foods are well tolerated and regarded as low in toxicity. As tannins they can bind proteins and minerals such as iron, so very high intakes may modestly reduce absorption of some nutrients.