In order to examine the effect of intake of green-tea beverage on iron and zinc status, tissue iron and zinc contents of rats administered with green-tea beverages were compared with those of the control rats without the tea beverages. Thirty-six male 4-weeks-old Wistar rats were divided into six groups. The first group was fed an AIN93G-based diet containing FeSO4 at a level of 12.5 μg Fe/g (low iron diet). The second and third groups were fed the low-iron diet to which a commercial green-tea beverage or a commercial catechin-rich green-tea beverage was added at a level of 800 mL/kg, respectively. The fourth group was fed an AIN93G-based diet containing FeSO4 at a level of 25.0 μg Fe/g (adequate iron diet). The fifth and sixth groups fed the adequate iron diet to which the commercial green-tea beverage or the commercial catechin-rich green-tea beverage was added, respectively. After the 4-weeks-feeding, significant higher hemoglobin contents and lower serum total iron binding capacities were observed in rats fed the adequate iron diets than those fed the low iron diets regardless of the administration with the green-tea beverages. Similarly, iron and zinc contents in the liver, kidney, femur and spleen as well as the apparent absorption of iron and zinc were not changed by the administration with the green-tea beverages while the tissue iron and zinc contents were influenced by the dietary iron level. These results indicate that the intake of green-tea beverage does not effect on iron and zinc absorption even in a low iron status.
