PBH recognized the importance of developing a database of key phytochemicals in fruits, vegetables, and nuts consumed in the U.S. USDA was committed to working in this area, since existing information was largely from small studies and studies done outside the U.S.

Sampling of about 50 fruits, vegetables, and nuts was done in supermarkets across the U.S. to help ensure data represented what consumers were purchasing. The sampling was done in two waves to minimize the impact of seasonality. The samples were analyzed for 24 phytochemicals - 8 carotenoids and 16 flavonoids - at USDA laboratories. A new analytical procedure developed by phytochemical expert, Dr. Gary Beecher, was used to analyze flavonoids. An ORAC analysis which measures total antioxidant capacity was done by Dr. Ronald Prior, who is a leading researcher in this field, at the USDA lab at the Arkansas Children's Nutrition Center.

USDA is in the process of incorporating data from these analyses into their existing databases. The carotenoid data have been incorporated into USDA's Standard Reference-17, while the ORAC and flavonoid data are expected to be added to the USDA website by mid-2005.

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