Iron deficiency is a widespread nutritional problem, and drinking too much tea may make it worse if you have low iron levels
Drinking too much caffeine from tea, or any other source, may cause feelings of nervousness, tension, and agitation.
Too much caffeine intake from tea may lower melatonin production and disrupt sleep cycles
Tannins in tea may irritate digestive tissue in sensitive people, causing symptoms like nausea or stomach pain
The caffeine in tea could cause heartburn or worsen existing acid reflux
Too much exposure to caffeine from tea during pregnancy may cause complications, such as miscarriage or low infant birth weight
Regularly drinking excessive amounts of caffeine from tea could cause chronic headaches
Large amounts of caffeine from tea can cause dizziness. This particular side effect is rare and only happens if your intake is too much
Even small amounts of regular tea intake could cause caffeine dependence. Withdrawal symptoms include tiredness, irritability, and headaches
In rare cases, green tea can cause bleeding disorders (11). Compounds in green tea lower levels of fibrinogen, a protein that helps clot blood
Drinking too much green tea increases the risk of bone disease such as osteoporosis in sensitive people