Nausea

Certain tea components can produce nausea, especially if eaten in excessive quantities or on an empty stomach. Tannins in tea leaves are responsible for tea's bitter, dry flavor. Tannins' astringent nature can also irritate digestive tissue, perhaps resulting in unpleasant symptoms such as nausea or stomach discomfort. The amount of tea necessary to have this effect varies greatly depending on the individual.

More sensitive people may have these symptoms after drinking as little as 1-2 cups (240-480 ml) of tea, however, others may be able to consume up to 5 cups (1.2 liters) without experiencing any negative effects. If you have any of these symptoms after drinking tea, you should consider limiting the amount you drink at one time. You might also try a dash of milk or some food with your tea. Tannins can attach to proteins and carbohydrates in the food, reducing digestive discomfort.