Tea Consumption Reduces Iron Bioavailability from NaFeEDTA in Nonanemic Women and Women with Iron Deficiency Anemia: Stable Iron Isotope Studies in Morocco.

BACKGROUND: Available data suggest that polyphenols from tea can inhibit iron absorption from ferric sodium EDTA (NaFeEDTA), but previous studies were done in small groups of mostly nonanemic adults. Morocco recently introduced national wheat flour fortification with NaFeEDTA, but tea is the national beverage and is consumed with most meals. OBJECTIVES: Our objective was to quantify bioavailability of iron from NaFeEDTA when added to a wheat flour-based meal in both nonanemic women and women with iron deficiency anemia (IDA), when consumed with and without traditional Moroccan green tea. METHODS: We recruited 2 groups of healthy Moroccan women (n = 46): women with IDA (n = 25; hemoglobin <12 g/dL,  serum ferritin <15 μg/L) and nonanemic women (n = 21). Each group received in random order 2 standardized test meals containing 6 mg Fe as isotopically labeled NaFeEDTA and either 300 mL of tea or water. Fractional iron absorption (FIA) was measured by the erythrocyte incorporation of stable iron isotopes after 14 d. We performed linear mixed-model analysis and post hoc sample t tests to assess the effects of group and tea on FIA. RESULTS: The polyphenol content of the tea serving was 492 mg. Tea consumption reduced iron absorption from NaFeEDTA by >85% in both IDA and nonanemic women. There were group (P