“Inhibition by black tea was 79 to 94 percent, peppermint tea 80 percent, pennyroyal 73 percent, cocoa 71 percent, vervain 59 percent, lime flower 52 percent and camomile 47 percent.
“At an identical concentration of total polyphenols, black tea was more inhibitory than cocoa, and more inhibitory than herbal teas camomile, vervain, lime flower and pennyroyal, but was of an equal inhibitor to peppermint tea.”
Non-haem iron is found predominantly in plant foods like whole grain, nuts, seeds, legumes and leafy greens.
The authors concluded that their findings demonstrate that herbal teas, as well as black tea, coffee and cocoa can be potent inhibitors of [non-haem iron] absorption.
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