Comparison of Various Databases for Estimation of Dietary Polyphenol Intake in the Population of Polish Adults

The primary aim of the study was to estimate the consumption of polyphenols in a population of 6661 subjects aged between 20 and 74 years representing a cross-section of the Polish society, and the second objective was to compare the intakes of flavonoids calculated on the basis of the two commonly used databases. Daily food consumption data were collected in 2003-2005 using a single 24-hour dietary recall. Intake of total polyphenols was estimated using an online Phenol-Explorer database, and flavonoid intake was determined using following data sources: the United States Department of Agriculture (USDA) database combined of flavonoid and isoflavone databases, and the Phenol-Explorer database. Total polyphenol intake, which was calculated with the Phenol-Explorer database, was 989 mg/day with the major contributions of phenolic acids 556 mg/day and flavonoids 403.5 mg/day. The flavonoid intake calculated on the basis of the USDA databases was 525 mg/day. This study found that tea is the primary source of polyphenols and flavonoids for the studied population, including mainly flavanols, while coffee is the most important contributor of phenolic acids, mostly hydroxycinnamic acids. Our study also demonstrated that flavonoid intakes estimated according to various databases may substantially differ. Further work should be undertaken to expand polyphenol databases to better reflect their food contents.