You may not absorb enough iron
The catechins in tea can alter your body’s ability to absorb iron. This means that even if you eat enough high-iron foods, you won’t get the benefits and could become anaemic. “Though most healthy people will not be affected by this, those who have iron deficiency or anaemia should abstain from large amounts of green tea,” recommends Dr. Kouri. This includes children, pregnant women and anyone with a history of kidney disease.
You could be at higher risk of bleeding
Drinking a large amount of tea every day could put you at risk for bleeding from a minor cut or bump. “It makes you more prone to bruising, explains Michelle Lee, MD, a board-certified plastic surgeon. “I require all my patients to stop drinking tea two to three weeks before surgery.”
Your medication may not work
While the benefits of tea seem unlimited, talk with your doctor and pharmacist before brewing a pot every day. “Catechins can interfere with some heart and blood pressure medications,” warns Dr. Kouri. “It is important to discuss this with your doctor.”