Estimated intake and major food sources of flavonoids among US adults: changes between 1999–2002 and 2007–2010 in NHANES

PURPOSE: This study was conducted to: (1) demonstrate an updated method for estimating flavonoid intake of US adults by combining USDA flavonoid databases and NHANES food consumption data; (2) document the intake and major food sources of flavonoids among US adults; and (3) determine whether the intake and major sources of dietary flavonoids have changed during the past decade in the USA. METHODS: A cross-sectional population-based study. Differences over time in the average daily intake and food sources of flavonoids were estimated using food consumption data from NHANES 1999–2002 (n = 8833) and 2007–2010 (n = 9801). RESULTS: The total flavonoid intake of US adults aged 19 years and older remained unchanged between 1999–2002 (201.9 mg/d) and 2007–2010 (200.1 mg/d), with tea being the top food source of flavonoids. However, intake of anthocyanidins increased during this period, mainly due to greater consumption of berries and wine, which was consistent with the increase in per capita consumption of these foods based on USDA food availability data. CONCLUSIONS: The results of this study provide updated information on flavonoid intake and food contributors and warrant further studies on the health implications of flavonoid intake.