Occurrence and biological significance of proanthocyanidins in the American diet.

Dietary intake of proanthocyanidins (PAs) has been largely unknown because of the lack of reliable values for their content in foods. Recent development of an analytical method for PAs has allowed the quantification of individual oligomers and polymers. This method has been employed to analyze food samples collected under the USDA National Food and Nutrition Analysis Program. A database of the PA content in common foods and also infant foods has been established. It has been shown that PAs account for a major fraction of flavonoids ingested in the US diet and infants and children appear to ingest more PAs than adults on the basis of body weight. These data will provide an opportunity to examine the association between PA intake and health and disease outcomes in epidemiological studies. PA analysis and the significance of PAs in nutrition and diet are reviewed.