Excessive tea consumption can inhibit the efficacy of oral iron treatment in iron-deficiency anemia.

Intestinal absorption of non-heme food iron may be inhibited by tea, which, on the contrary, does not exert any appreciable effect on heme iron assimilation. Therefore, while an iron-deficiency anemia cannot develop in non-vegetarian subjects as a consequence of tea consumption only, it is possible that tea could inhibit the therapeutic effect of oral iron drugs, which are usually non-hemic ferrous salts, in iron-deficient subjects. This view is supported by the case we describe here, a young woman affected by hypermenorrhea and iron-deficiency anemia, who did not respond to oral iron treatment until she stopped her long-established habit of consuming large quantities of tea. We also believe that oral iron drugs should never be taken together with a cup of tea; therefore we think it useful to advise our iron-deficient patients clearly not to combine tea with the oral consumption of non-hemic ferrous salts.