Tonines are a type of chemical that can be found in large amounts in tea. Some foods have tannins that can bind to the iron, making it impossible for your body to absorb.
One of the most common nutrient deficiencies in the world is iron deficiency. If you already have low iron levels, drinking too much tea may make your situation worse.
Researchers have found that tea tannins are more likely to stop the intake of iron from plant-based foods than from animal-based foods. So, if you can't have any animal products, you might want to be extra careful about how much tea you drink.
Different types of tea and different ways of making them can have very different amounts of tannins. That being said, most people should probably stay within the range of 3 cups (710 ml) or less per day.
Caffeine is naturally found in tea leaves. If you drink too much caffeine, whether from tea or another source, it may make you feel anxious, stressed, and restless.
Not getting enough sleep Because tea naturally has caffeine in it, drinking too much of it may make it hard to sleep.
Some chemicals in tea can make you feel sick, especially if you drink a lot of it or right before bed.
Caffeine in tea may give you heartburn or make acid reflux symptoms worse if you already have them.