There is speculation that the tannins found in coffee, tea, and chocolate may interfere with iron absorption.
Scientists from Tunisia came to the conclusion about the negative impact of tea drinking on iron absorption, but they conducted the experiment on rats.
The 2009 International Journal of Cardiology article “Green Tea Does Not Inhibit Iron Absorption” states that green tea does not interfere with iron absorption.
In 2008, however, a study in India showed that drinking tea with meals could cut iron absorption in half.
The good news, however, is that a study found that vitamin C tripled iron absorption. Therefore, if you drink tea with lemon or get vitamin C from foods such as broccoli, tropical fruits, bell peppers, etc., then this should not be a problem.
If, however, you do not like tea with lemon and do not eat these products, then … If you are a woman, then give up tea and coffee during menstruation, replace them with cocoa and mint tea, or postpone tea drinking and eating, at least for an hour. And if you’re a postmenopausal man or woman, decreased iron absorption may not necessarily be harmful to you. In fact, coffee’s ability to influence iron absorption explains why coffee consumption protects against iron overload-related diseases such as diabetes and gout.