In both instances, the culprit impeding iron absorption is tannin. Tannins are potent polyphenol compounds that give tea, coffee, and red wine their dry and puckery taste. With coffee, tannin ...

“Tannins are a type of polyphenol that bond to iron in certain foods, inhibiting its absorption in your digestive system.” That’s particularly the case with plant-based (non-heme) iron ...

But drinking excessive amounts of green tea, matcha, or any other drinks that are high in polyphenols (like white tea) can inhibit iron absorption, explains Jessica Strawn, MA, RDN. "Any food or drink ...